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Silicon Laboratories (NASDAQ:SLAB)
Q4 2018 Earnings Conference Call
Jan. 30, 2019 8:30 a.m. ET

Contents:

  • Prepared Remarks
  • Questions and Answers
  • Call Participants

Prepared Remarks:

Operator

Good morning. My name is Anita and I will be your conference operator today. At this time, I would like to welcome everyone to Silicon Labs' fourth-quarter fiscal 2018 earnings conference call. [Operator instructions] Please note, this event is being recorded.

I would now like to turn the conference over to Jalene Hoover, director of investor relations and international finance. Jalene, please go ahead.

Jalene Hoover -- Director of Investor Relations

Thank you, Anita, and good morning, everyone. Tyson Tuttle, chief executive officer; and John Hollister, chief financial officer, are on today's call. We will discuss our financial performance and review our business activities [Inaudible] After our prepared comments, we will take questions. Our earnings press release and the accompanying financial tables are available in the Investor Relations section of our website at www.silabs.com.

This call is also being webcast and a replay will be available for four weeks. Our comments today will include forward-looking statements subject to risks and uncertainties. W base these forward-looking statements on information available to us as of the date of this conference call and assume no obligation to update these statements in the future. We encourage you to review our SEC filings, which identify important risk factors that could cause actual results to differ materially from those contained in any forward-looking statement.

Additionally, during our call today, we'll refer to certain non-GAAP financial information. A reconciliation of our GAAP to non-GAAP results is included in the company's earnings press release and also on the Investor Relations section of our Silicon Labs website. I would now like to turn the call over to Silicon Labs Chief Financial Officer John Hollister.

John Hollister -- Chief Financial Officer

Thanks, Jalene. Revenue for the fourth quarter ended at approximately $216 million, $5 million less than the low end of our guidance and down 6% sequentially. We saw a deceleration in revenue as we exited Q4 with broad market weakness, primarily impacting IoT and infrastructure. For the full year, we grew revenue by $100 million or 13% ending at $868 million with $63 million derived from our organic portfolio and $37 million from the addition of Z-Wave.

IoT ended the quarter at $119 million, down 5% sequentially and up 9% Q4 year on year. Fourth-quarter wireless revenue was roughly flat sequentially. Q4 MCU revenue was down due to a weakening macro environment. Revenue from infrastructure products was down, ending at $46 million, declining 13% sequentially and up 15% Q4 year on year.

Isolation product sales declined more than we expected on industrial weakness, particularly in China. Timing revenue was down slightly. Fourth-quarter broadcast revenue was slightly better than we expected ending at $35 million dollars, down 3% both sequentially and year on year. Q4 automotive revenue was down while consumer revenue was up sequentially.

In 2018, we increased our global market share in flat panel TVs to more than 80% with our industry-leading TV tuners. Access product sales declined for the quarter ending at $15 million, down about 7% sequentially and 8% Q4 year on year. Looking at fourth-quarter revenue by end market, we saw broad sequential declines in the industrial, communications, and automotive segments. The consumer end market was up for the quarter on strength in broadcasts.

Looking at full-year 2018, we saw the greatest strength in the industrial end market, which grew over 20%. The communications and automotive end markets were also up for the year. Geographically we saw the greatest weakness in fourth quarter sequential revenue performance in the Americas, led by declines in wireless, automotive, isolation, and access. APAC was down slightly with declines in broad-based MCUs and isolation products offset some by growth in Access.

Europe was up slightly for the quarter on strength in wireless. Looking at full-year 2018, we saw growth in all geographies, led by the Americas and followed by APAC. Distribution revenue was 69% of total Q4 revenue. For 2018, our 10 largest end customers accounted for 20% of our revenues and no customer represented more than 5%.

Non-GAAP gross margin for the quarter ended slightly better than we expected at 60.6% on product mix. Q4 non-GAAP OPEX ended at $88 million in line with expectations. Non-GAAP R&D expense for the quarter was $49 million, up slightly on seasonal trends and new products costs and non-GAAP SG&A ended at $39 million, flat to Q3. Non-GAAP operating margin for the quarter ended at 19.6%.

For the full-year, non-GAAP operating margin improved 70 basis points over 2017, ending at 21.2%. Our non-GAAP effective tax rate was 6.4% for the quarter, driven primarily by lower taxes on our offshore earnings and a benefit from the annual U.S. R&D tax credit. Non-GAAP EPS ended at $0.91 at the low end of our guidance range, primarily due to lower fourth-quarter revenue.

Non-GAAP earnings for the full year improved to $3.71, up 14% versus 2017. On a GAAP basis, our Q4 gross margins ended at 60.4%. GAAP operating expenses were $112 million in line with expectations with R&D expenses at $63 million and SG&A expenses at $49 million. Stock compensation expense was $13 million for the quarter with amortization of intangible assets ending at $11 million, both in line with expectations.

We had a $2 million or 15.6 GAAP effective tax benefit in the fourth quarter and GAAP diluted earnings per share were $0.35. Full-year 2018 GAAP earnings ended at $1.90. Turning now to the balance sheet, we ended the year with $620 million in cash and investments. Accounts receivable were down for the quarter ending at $73 million or 31 days sales outstanding.

Our operations team leveraged our scalable fabulous manufacturing model and effectively managed inventory, which declined to $75 million or 4.6 turns, in line with our corporate objectives. Operating cash flow for the year was $174 million. We executed additional share repurchases in Q4, bringing the 2018 year-to-date total to $39 million. Heading into 2019, we have approximately $160 million of our share repurchase authorization remaining.

I will now cover guidance for the first quarter. In light of macro uncertainty and volatility, we are broadening our guidance range and expects first-quarter revenue to be between $183 million to $193 million. We expect our non-GAAP gross margin to be 60%. In response to the anticipated decline in first-quarter revenue, we are slowing OPEX growth and expects Q1 non-GAAP operating expenses to be approximately $90 million.

Our non-GAAP effective tax rate for the first quarter is expected to be 13% and we expect non-GAAP earnings per share to be in the range of $0.42 to $0.52. On a GAAP basis, we expect gross margin to be 60%. We expect GAAP operating expenses to be $114 million. In Q1, we expect a GAAP effective tax rate of approximately 10% with a GAAP loss per share between $0.11 and $0.01.

I will now turn the call over to Tyson.

Tyson Tuttle -- Chief Executive Officer

Thank you, John. We are proud of our performance in 2018, which was a strong year for Silicon Laboratories in many dimensions. We completed the successful acquisition of Z-Wave and grew our revenue by $100 million. We strengthened our team with the addition of critical leadership, sales, applications, customer support, and software expertise.

Silicon Labs' innovative culture attracts outstanding talent, who are foundational to our success. In 2018, our opportunity pipeline achieved record growth, up more than 40% to $11 billion in lifetime revenue. We also achieved record design wins, which increased approximately 30% year on year, providing a strong tailwind for future growth and a validation of our strategy. Fourth-quarter results were weaker than we expected and our first quarter outlook is down sharply with a broad-based slowdown in our bookings and revenue outlook.

We attribute these shortfalls primarily to the macro environment and not to share loss. Economic conditions are decelerating in major markets around the world, which is causing an acceleration of the semiconductor industry down cycle. In Q4, for example, we saw sequential declines in our MCU and isolation products, which are among our broadest product lines and most strongly correlated to overall economic conditions. China, in particular, is facing a difficult environment, with a slowdown in overall GDP performance and factory activity, combined with customers moving production to other geographies due to concerns over tariffs.

We have also seen an accumulation of inventory at certain of our key end customers. As we enter 2019, we are closely monitoring the macro environment and managing headcount growth and discretionary expenditures to drive an OPEX level that is lower than initially contemplated. Turning now to product updates, Infrastructure delivered a phenomenal 2018 with revenue growing by more than 30% in design win lifetime revenue up approximately 50%. Isolation product revenue grew more than 40% annually and timing products grew 25% over the same period.

Silicon Labs digital isolation products continue to replace traditional optocouplers, enabling higher performance, reliability, integration, and best-in-class safety for designs requiring protection from high voltages. In 2018, we saw strength across a broad range of applications, including power supplies, solar, industrial, and automotive. We have established ourselves as a leading provider of digital isolation technology to the cloud, telecom, and electric vehicle markets. Traditionally, our timing products have targeted the core optical networking market.

During 2018, we expanded and diversified our timing revenue into industrial, data center, and wireless infrastructure markets, which combined now represent approximately 40% of overall timing revenue. IoT products grew 17% in 2018 to more than $460 million, including $37 million from our acquisition of Z-Wave in Q2. Wireless products now make up more than 60% of total IoT revenue and delivered nearly 30% year-on-year growth. We saw modest annual growth in our MCU and sensor products.

Despite delayed product ramps in 2018 with high-volume lighting customers, the transition from SMETS1 to SMETS2 in the U.K. smart metering market and macro factors, we remain confident in our design win pipeline and market position. For full-year 2018, we saw approximately 50% growth in our IoT opportunity funnel to $8 billion and nearly nearly 30% growth in IoT design win lifetime revenue. We continue to strengthen our portfolio, driving capabilities and differentiation, while advancing security and growing ecosystem partnerships.

Our Connectivity portfolio is gaining significant traction as we target low-power wireless end nodes with a broad range of protocols and optimal combinations for target market segments in smart home, industrial, metering, commercial, consumer, and lighting. In Q4, we launched the next-generation Z-Wave 700 on our Wireless Gecko platform, delivering on our vision and platform integration roadmap in enhancing our product offering to the Z-Wave ecosystem. Our new smart home platform builds on Z-Wave's industry-leading S2 security and interoperability, improving battery life, and adding higher performance and longer-range RF capabilities. IDC estimates the worldwide smartphone market will grow at an approximate 20% compound annual growth rate from 2017 to 2022 as the market balloons to $1.3 billion devices shipped annually, with much of that adoption in growth driven by sensors, enabling AI and Edge computing applications.

Advances in wireless technology such as Z-Wave 700 are driving the battery-powered sensor trend and making these devices easier to install and deploy. Silicon Labs is well-positioned to consolidate the smart home experience and drive IoT adoption in this market. Earlier this week, we announced the release of new Bluetooth 5.1 software for our Wireless Gecko platform, further expanding the capabilities of our portfolio. Silicon Labs new solution moves beyond point-to-point connectivity to include advanced angle of arrival and angle of departure technology for more precise indoor position positioning and location services used in a wide range of applications, including factory automation, retail, and smart cities.

During the quarter, we announced the expansion of our groundbreaking Wi-Fi portfolio, featuring modules and transceivers designed specifically for the IoT. We offer the lowest power Wi-Fi devices on the planet, enabling IoT in-node designs that weren't possible until now. Developers can create products with best-in-class power efficiency, superior interference rejection, wireless coexistence, and advance security. The portfolio cuts power consumption in half compared to competitive offerings, providing an ideal Wi-Fi solution for power-sensitive connected products, including battery-operated IP security cameras, point-of-sale scanners, asset trackers, and personal medical devices.

Earlier this month at CES in Las Vegas, we saw growing momentum in the IoT and a lot of customer excitement about our solutions. At CES, we announced that Xiaomi, a leading IoT ecosystem provider in China launched new smart lighting products based on Silicon Labs' Wireless Gecko SoCs and Bluetooth mesh software. We are seeing increasing deployment of Bluetooth mesh in China's fast-growing smart home market. And Xiaomi is poised to ship mesh-enabled smart home products at scale, driving further adoption of this versatile, ubiquitous, wireless technology.

Also at CES, Tuya, a leading AI and IoT platform provider in China, announced they are using Silicon Labs' Wireless Gecko platform, including SoCs, ZigBee, and Bluetooth software to enable their smart multi-protocol products to easily connect to multi-node mesh networks deployed in smart homes. Tuya's production-ready smart solutions address the real world needs of IoT manufacturers, supply chains, e-commerce channels, and retailers worldwide, and we are playing a role in their success. I am delighted to announce Christy Wyatt's appointment to our board of directors. As a thought leader in the cybersecurity industry, Christy brings extensive experience developing and scaling technology companies.

She is currently CEO of Absolute Software Corporation, which specializes in self-healing endpoint security technology. With more than two decades of leadership experience, including Citigroup, Motorola Mobility, Apple, and Palm, Christy's skills and expertise will be invaluable to Silicon Labs as we chart our course into the future. In 2018, we capped off an outstanding year by winning for the fourth year in a row the Global Semiconductor Alliance's Most Respected Public Semiconductor Company award. It's a great honor to be chosen by our industry peers based on best products, vision, and future opportunities.

Despite current volatility, we remain confident about our longer term ability to outperform the market. We are focused on executing on our product roadmaps and converting a large pipeline of opportunities into additional wins and share gains. The technologies we are developing are enabling our customers to transform industries and improve life. And together, we are creating a smarter, more connected world.

Thank you for your time and attention. Before we take your questions, I'd like to turn the call back to Jalene.

Jalene Hoover -- Director of Investor Relations

Thank you, Tyson. We would now like to open the call up for your questions. [Operator instructions] Anita? 

Questions and Answers:

Operator

Thank you. We will now begin the question-and-answer session. [Operator instructions] The first question today comes from Max Ramsay with Cowen. Please go ahead.

Matt Ramsay -- Cowen and Company -- Analyst

Thank you very much. Good morning, guys. Tyson, I'm -- obviously, the soft and bit cloudy macro environment, but maybe you can give us a little more color in terms of end market weakness into the first quarter. If there's any differentiation across the end markets in the IoT business? And then, second, to what extent do you feel like the outlook you've given for the first quarter is reflecting just maybe inventory have been taking down at some of the channel partners in [Inaudible] versus the organic sort of slower growth that we're seeing in the end markets? Any context there will be helpful.

Thank you.

Tyson Tuttle -- Chief Executive Officer

Yes, so, let me take the first part, and I'll let John talk about the second part. In terms of end market weakness, if we talk about IoT, we've had continuing weakness in the U.K. smart metering market, which we expect to recover in 2019. And we also have had some weakness in the lighting market, which has continued in some excess inventory there.

But again, we believe that that will be ramping as we move throughout the year. So, those two did contribute to the Q4 results and continued into Q1 or continuing into Q1. If you look at really the MCU business and our Isolation business are both very broad in terms of the applications and customer base. And both of those were impacted by the macro and just down overall, and particularly in China.

And so, I think that we've seen a number of customer push-offs and inventory situations in the China market in particular. And so that was -- that's a factor as we exited Q4 and into Q1. So, it's really the broad product lines have the most significant impact on the numbers and overall. In timing, it was OK.

And in wireless continued to see some ramp but, overall, the general direction was down as we exited Q4.

John Hollister -- Chief Financial Officer

Yes, Matt. This is John. I'd just like to add on that on the inventory side, we do think there is a takedown of end-customer inventory and process. And we also see that distributors were aggressively managing inventory as we rounded out the fourth quarter heading into the first quarter.

That should bode well for a recovery as the days in inventory and distribution are not excessive, but it did impact our final Q4 results last year.

Matt Ramsay -- Cowen and Company -- Analyst

Got it. Thanks, guys. That's helpful. Just a follow on to that last comment, John, maybe -- I know it's a tough environment to look out too far.

We're just trying to get our heads around here and questions I'm getting around the full year for the IoT business. You guys give longer-term targets and that target has been 20% growth for a while. And obviously, we're starting off a rough spot for the year. So, any thoughts about annualized growth for 2019 would be helpful realizing that's a tough to ask in this state, but appreciate it.

Thank you.

John Hollister -- Chief Financial Officer

Yes, you bet, Matt. The commentary there is we do expect a rebound in the second quarter. That's based on strong design win performance last year, combined with inputs from our customers and distribution partners as well as healthier bookings rates for last couple of weeks certainly versus what we saw in the month prior. So rebound in Q2, followed by onward growth in the second half is our expectation right now.

And of course, we'll be able to provide better indications of that as the year progresses here.

Operator

The next question comes from Gary Mobley with Benchmark. Please go ahead.

Gary Mobley -- Benchmark -- Analyst

Good morning, everyone. Thanks for taking my question. Given that we're starting the year out in a bit of a whole with respect to top line, even if you see better than seasonal trends as the year unfolds, it's going to be tough to grow revenue in 2019. And as well, just given where operating margin is expected to start in the first quarter, it's going to be a pretty tough comp on the operating margin in 2019.

So the question is how long are you willing to go before becoming more proactive in rightsizing the OPEX to delivery some stabilization there, if not improvement?

John Hollister -- Chief Financial Officer

Yes, Gary, this is John. First ofd, I think your observations there are sound. But we think the thing to do is to be diligent and cautious in our spending, but not overreact. And we do see very strong design win momentum in the business.

We have a leading position and strong secular growth markets, and feel it's very important to maintain that position. We'll see how the year unfolds and we will remain diligent in that. But I think right now we've taken steps to control the OPEX here in first quarter. And we'll continue to monitor this as the year progresses.

Gary Mobley -- Benchmark -- Analyst

OK. As a follow up, I just have a house keeping question. John, what would you expect your full-year 2019 non-GAAP tax rate to approximate?

John Hollister -- Chief Financial Officer

13% is the best view I can give you at the momentary.

Gary Mobley -- Benchmark -- Analyst

All right. Thank you, everyone.

John Hollister -- Chief Financial Officer

Sure.

Operator

The next question comes from Cody Acree with Loop Capital. Please go ahead.

Cody Acree -- Loop Capital -- Analyst

Yes. Thanks, guys, for the question. So Maxim last night said that they were starting to see some improved order trends and improved bookings over the last few weeks broadly. It sounds like your comments just in the last question or two were somewhat similar.

Are you starting to see any improvement in the year?

John Hollister -- Chief Financial Officer

Yes. Cody, this is John. The answer is yes. We have seen better performance there in the last few weeks over the month prior.

Yes, we have.

Cody Acree -- Loop Capital -- Analyst

Can you maybe give us any visibility as to end markets that you're starting to see that in?

John Hollister -- Chief Financial Officer

It's fairly consistent. And I just want to add on to some of the commentary Tyson was taking about moments ago. We also have seen a relatively weak automotive market in the second half of 2018 and heading into the beginning of this year. We've seen that begin to improve a bit, but its improvement in the bookings system, fairly broad-based.

Cody Acree -- Loop Capital -- Analyst

And I guess, lastly then just for your weakness in China, where are you specifically seeing that? And are you starting to see any trends change in China?

John Hollister -- Chief Financial Officer

A little too early to call it there specifically. But just adding on to what Tyson was saying, MCU and Isolation were particularly weak in China as we rounded out the year.

Cody Acree -- Loop Capital -- Analyst

All right. Thank you, guys.

Operator

The next question comes from Blayne Curtis with Barclays. Please go ahead.

Blayne Curtis -- Barclays Investment Bank -- Analyst

Hey, guys. Thanks for taking my question. Maybe just turn around. As you look at this year, it's probably difficult to give full-year guidance.

So, maybe you can highlight in certain products or areas that you actually expect to see some kind of secular growth versus, obviously, the macro slowdown? Thanks.

John Hollister -- Chief Financial Officer

Yes. So, I think the best indication of the growth potential in the business is in the pipeline and in the design win traction. So, we had 50% growth of our infrastructure design win pipeline. And in IoT, we had about a 30% year-on-year growth in the design win pipeline.

And so that's not in the pipeline but in the design wins themselves. And that translates into revenue and would be anticipated to ramp as we move through 2018 or 2019. So, you look at the number of customers, you see us a fantastic and tons of opportunities, multiple programs, multiple large customers. The question is just how quickly will that turn into revenue and how will the macro impacts this.

We're going into Chinese New Year, we've got a Trade War, we've got debt concerns and other things. But at the same time, we're quite bullish in terms of our product portfolio, the areas that we're in in terms of IoT and smart home and lighting and commercial. And lots of things around IoT are doing well. The trend toward all the data out in the market going into data centers and high speed communications and wireless and our expansion into those areas and timing.

And then in Isolation, the trend toward electrification, electric vehicles, and all of the power devices that go out into the market, solar, motor controls, power supply. So, we're well positioned in terms of the portfolio, well positioned competitively and well positioned in terms of the design win traction that we have, but that's really not immune to macro. And we'll see how we come out of the first quarter. Right now things are looking like they are picking up a bit, but it's still a little bit really and we need to get through Q1 and see how the rest of year is going to turn out.

Blayne Curtis -- Barclays Investment Bank -- Analyst

Thanks. And then I just wanted to ask you, the one area that seems to be good is 5G infrastructure. I know your timing has been more wired focus. You did mention some early ramps in wireless.

Can you just give us a picture as to when you see that being more material for you?

John Hollister -- Chief Financial Officer

We have design wins in some of the early 5G. We're calling it 4.5G base stations that are going to start ramping this year. And then certainly 5G, as we look a little bit further out. So, we've got a strong roadmap and strong engagements on the wireless side with our timing products.

There is also little bit on the isolation products within the power supplies for all of those types of devices. But just overall having 40% of the timing revenue now outside the core optical networking market really shows -- and we've been talking about this for a long time, but a lot of these are very high quality, long-term wins that take a while to ramp. But seeing industrial data center and wireless all ramping on timing bodes well for the portfolio.

Blayne Curtis -- Barclays Investment Bank -- Analyst

Thanks, John.

Operator

The next question comes from Suji Desilva with ROTH Capital. Please go ahead.

Suji Desilva -- ROTH Capital -- Analyst

Hi, Tyson. Hi, John. So, maybe you can kind of step back, Tyson, describe this downturn that you're seeing, industrial or broadly, how it compares to past cycles? If you can give us some color there that might be helpful. It kind of came on very quickly, so that context will be appreciated.

John Hollister -- Chief Financial Officer

Yes. I mean, it's been nearly a decade since we've had any sort of a macro correction. The question is is this one going to be short-lived with a quick rebound or is it going to be more protracted? And I think that really depends a little bit on how the U.S.-China relationship turns out in terms of Huawei-ZTE, in terms of the tariffs. We've certainly seen a bit more churn in terms of moving production from one location to another and inventory and lots of movements there, which has caused pause in lot of the ordering patterns.

So, I would say that the geopolitical factors and the trade factors are much more turbulent now than they were before. This is being caused by different set of factors out in the macro economy. It's not a housing bubble. You've also got U.S.

consumer confidence remains strong. And we finally have a let-up on that, at least a pause on the government shutdown. And hopefully that -- we can sale through that. So, if we can keep the consumer confidence up and we see a more normal return to growth, I think that then we can start seeing the results of the design win.

So, hopefully this is a little bit shorter term than what we saw back in 2008. But we really have to get through the year to see how it's all going to turn out.

Suji Desilva -- ROTH Capital -- Analyst

That's helpful, Tyson. And then one quick follow-up on the Wi-Fi part of the business, which is newer. Can you just talk about your expectations for how much -- how quickly that ramps and grow? Or does that remain a kind of a niche effort relative to your Bluetooth and ZigBee connectivity? And what's your prospects -- what are the prospects for that business?

Tyson Tuttle -- Chief Executive Officer

Yes. We're excited about our Wi-Fi portfolio. We've been out sampling this to a lot of customers for about a year. It creates the lowest power Wi-Fi solution, and we have a lot of customers that are using multiple protocols that are using Wi-Fi and Bluetooth or Wi-Fi and ZigBee in different configurations.

And as we integrate these solutions together and are able to offer that, that further strengthens both the Wi-Fi portfolio, but certainly our position in the rest of the portfolio as well. So, we see that product ramping modestly this year. And it's a very important standard. There were a lot of Wi-Fi devices out in -- at CES, and we'll see how the market uptake is on a number of these things that were designed into.

But it's an exciting new expansion of our SAM, and I think reflects our long-term commitment to be the leading provider of IoT wireless technology.

Suji Desilva -- ROTH Capital -- Analyst

OK. Thanks, guys.

Tyson Tuttle -- Chief Executive Officer

Thank you.

Operator

The next question comes from Tore Svanberg with Stifel. Please go ahead.

Tore Svanberg -- Stifel Financial Corp. -- Analyst

Yes. Thank you. First question, Tyson, you talked before about how security is becoming a very important part of your IoT offering and that you're starting to embed security on a lot of your newer products. Could you talk a little bit about what that means for you when it comes to content or maybe growth reaccelerating in IoT?

Tyson Tuttle -- Chief Executive Officer

Security is an absolutely important technology and set of capabilities for the IoT. And I think to the extent that we can make security bullet proof and easy to use, it will accelerate the market for these devices. If you look at our first-gen devices, we have a strong offering of security technology and the ability to drive very low-power encryption and advanced algorithms. And that's integrated within our SDK.

As we move out to our second generation platform, we're integrating additional secure element functionality into the devices. Think of it as payment-level security, where you can store keys, and you have very advanced hardware, so you can't tamper -- anti-tamper, and you can't hack into these devices even more than you would have in the first gen. So, it's something that we're investing in. It also opens up some additional opportunities to add key management.

And you can individually address devices and push software updates in a very, very secure manner. And that opens up some potential new capabilities for our customers, but also capabilities for us to potentially monetize that as we move out in time. But the security is absolutely essential to the deployment and security of all these IoT devices and making people confident that it's bulletproof is, I think, really essential. So it's a huge amount of investment and attention that we're putting onto the portfolio around security, and we think that can be a significant differentiator for us.

Tore Svanberg -- Stifel Financial Corp. -- Analyst

That's helpful. And as my follow-up for John, John you're talking about being prudent on OPEX, yet it's guided to be up sequentially. I believe it's about 48% of revenue. Will you take further actions here to try and get the OPEX down somewhat?

John Hollister -- Chief Financial Officer

Yes. Tore, we -- there is a seasonal aspects to the increase in the first quarter. You have a multibillion dollar increase just naturally, given the seasonal French reset that we go through every year. So, putting that aside, we are managing the OPEX cautiously and we'll continue to monitor this as we go forward and we look forward for a recovery in the business really as the key and X factor to monitor here.

Tore Svanberg -- Stifel Financial Corp. -- Analyst

OK. Thank you.

Operator

The next question comes from Alessandra Vecchi with William Blair. Please go ahead.

Alessandra Vecchi -- William Blair -- Analyst

Hey, guys. Just as a clarification, when you said your wireless revenue is roughly flat sequentially, was that on organic basis or was that including Z-Wave?

John Hollister -- Chief Financial Officer

That was including Z-Wave.

Alessandra Vecchi -- William Blair -- Analyst

OK. And then additionally, as you pointed out, your broadcast business came in better than expected and quite better than I had modeled. How should we think about that going forward into next year? I know your strategic goal has been down 10% annually, but do you think this sort of the strength on the consumer side can hold up a little bit longer than expected?

John Hollister -- Chief Financial Officer

Yes, if you look at broadcast overall for the year, while Q4 was relatively flat, it was down about 8% year on year, and we have a target of 10% down. And so we actually held share a little bit more. We added 80% design market share in the flat panel TVs with our tenders. And we see that model of 10% down both for Access and Broadcast as being consistent for the long-term performance of those.

So, we outperformed that in both for Access and Broadcast this last year and maintained share, and feel good about our competitive position in those markets.

Alessandra Vecchi -- William Blair -- Analyst

OK. Thank you.

Operator

[Operator instructions] The next question comes from Rajvindra Gill with Needham & Company. Please go ahead.

Rajvindra Gill -- Needham & Company -- Analyst

[Inaudible] Z-Wave and organic --

John Hollister -- Chief Financial Officer

Hey, Raji, it's John. We didn't catch you at the beginning. Please begin your question from the top.

Rajvindra Gill -- Needham & Company -- Analyst

I apologize if this question was asked. I joined a bit late, but the IoT kind of breakdown between organic versus Z-Wave, if you look at your 10-Q, in September, you did about $20.5 million of Z-Wave since March. So that equated to about $30 million of revenue from Z-Wave in September. And so, if we assume kind of a similar type of rate in Q4, the organic IoT business is going to be down about 3% year over year in Q4 and maybe down again on a year-over-year basis in Q1.

You had mentioned that you see -- saw continued weakness in the U.K. smart metering. I was under the impression that those customers had transitioned to the SMETS2 standard and that we are going to start to see more proliferation there. Does this has to do with more macro related issues in England itself related to Brexit? I just wanted to get little bit clarity on IoT breakdown in U.K.

smart metering and expectations of a ramp in the second half because that's very -- your IoT organic growth is very dependent on those specific areas.

John Hollister -- Chief Financial Officer

Yes, so if you look at the organic growth, and we kind break that down within IoT, we saw microcontrollers down fairly strongly -- double-digit down from Q3 to Q4 and anticipated to take another step down here in Q1. So that's the microcontroller portion. So that's definitely a strong drag on the year-on-year comparison. That's really macro across the board 8-bit, 32-bit low-power automotive, broad-based.

All of the microcontrollers are consistently seeing those trends. If you look within the wireless portfolio, we've actually seen our -- the more industrial proprietary wireless stuff be fairly stable as we go from Q3 to Q4 into Q1. And those are heavy industrial compatible with legacy networks and also upgradable to more advance things. So, that's actually held in fairly well.

Where we seen a stronger impact has been in the ZigBee, in the mesh 15.4 area. And we've seen -- we saw pretty solid growth as we came through the year of Q3 but then as we came into Q4, that took a hit. That was overall for the year. It was impacted by the smart energy and lighting.

And we thought it was going to be stronger and we've got those design wins in place. But here, Q4 and Q1, some of that is kind of, I wouldn't call it consumer, but its light industrial, it's more of the smart home type stuff. And we've seen Q4 and Q1, some weakness there although very strong design wins. And as we look out into the year, both lighting -- those ramps really taking hold and that inventory burning off.

And then the smart energy, we think in Q2 the SMETS2 transition is going to really start kicking in in the smart energy steps. So, on the 15.4 ZigBee side, this really looks like a kind of a two-quarter hold with some rebound in Q2 and then a very strong second half with the 15.4. Then on the Bluetooth side, we've been ramping, we talked about Xiaomi, and a lot of these Chinese ecosystems. And they've been very, very successful out in the market.

So, we see continued -- a little bit of weakness in Q4 and Q1 although that's on the back of what should have been stronger growth. But then as we go out into '19, that Bluetooth portion, we actually anticipate some share gains there and also just the deployment of the Bluetooth mesh technology. So overall, again, wireless kind of flat from Q3 to Q4, which should have been growth had we not have the macro impact that we saw in December and coming into the quarter. And then we do see a rebound in that coming -- going into Q2, and then the design win traction should really take hold in the second half.

So, that's on the IoT side. In terms of year-on-year compares, we're optimistic about the year, but we're definitely starting off with Q1 weaker than we would have hoped, but we'll see how it turns out. But overall, the design win up 30% year on year last year, and that's on a pretty big number. We feel good about what we've been able to do on the sales side and driving the pipeline and driving the customer engagement and the conversion of that into revenue.

We'll see if we -- as we come in Q2 and into the second half. But it's looking solid from my prospective in terms of the validation of the strategy and the roadmap, but it's got to turn into numbers.

Rajvindra Gill -- Needham & Company -- Analyst

No, that's helpful. And for my follow-up, with respect to your direct China exposure products that are consumed in China, it might be difficult to quantify, but what percentage of the MCU, the isolation is exposed to China directly? And I'm just -- a little bit cautious on this idea that the booking rates are improving in the last couple weeks. I mean, what is the basis of the booking rates improving? What's the rationale? Any kind of insight on that would be helpful. Thanks.

Tyson Tuttle -- Chief Executive Officer

Yes, in terms of the direct China exposure, we're about -- it's about 30% of our revenue is designed into domestic China customers that then either shift worldwide or would shift into the domestic China market. We do have about 60%-plus of our revenue shifts into China, but then that's really an ODM relationship or something like that. So it's about -- that's fairly -- you got microcontroller, you've got Isolation, you've got the Infrastructure business, Broadcast, all those are -- do have business within China. I think just relative to a number of other semiconductor companies.

I mean, not only do we have a fabulous model, where we can really scale our supply chain, but -- yes, we do probably have a little bit less direct China exposure than some of our direct competitors.

John Hollister -- Chief Financial Officer

Yes, Rajvi, on the bookings -- this is John. It's really seeing an improvement and what we're seeing from our distribution partners and that's coming on the back with relatively light inventory levels and distribution, which bodes well for us. And I would say, from here, through the balance of Q1 with, I would say, moderate bookings performance for the remainder of this quarter, we're confident in our guidance that we've provided this morning. And seeing how that's affecting Q2 in terms of the bookings, we're in line with a rebound in business for Q2 based on what we see so far.

Now, all of that said, yes, there is greater volatility right now than what we've seen in the past and what we'd like to see, but we do see those as positive indicators.

Rajvindra Gill -- Needham & Company -- Analyst

No, that's great. Thank you so much. Appreciate it.

Operator

This concludes the question-and-answer session. I would now like to call -- turn the call back over to Jalene Hoover. Please go ahead.

Jalene Hoover -- Director of Investor Relations

Thank you, Anita, and thank you all for joining us this morning. This concludes today's call.

Operator

[Operator signoff]

Duration: 49 minutes

Call Participants:

Jalene Hoover -- Director of Investor Relations

John Hollister -- Chief Financial Officer

Tyson Tuttle -- Chief Executive Officer

Matt Ramsay -- Cowen and Company -- Analyst

Tyson Tuttle -- Chief Executive Officer

John Hollister -- Chief Financial Officer

Gary Mobley -- Benchmark -- Analyst

Cody Acree -- Loop Capital -- Analyst

Blayne Curtis -- Barclays Investment Bank -- Analyst

Suji Desilva -- ROTH Capital -- Analyst

Tore Svanberg -- Stifel Financial Corp. -- Analyst

Alessandra Vecchi -- William Blair -- Analyst

Rajvindra Gill -- Needham & Company -- Analyst

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