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Market landscape
There are more than 30 touch IC vendors worldwide, and competition is intense. After several years of development, China-based IC design firms have begun to gain advantages in local support and cost control, and the technological gap with international vendors has been narrowing. More companies are entering the touch IC field. Atmel, Synaptics and Cypress still hold more than 60% of the touch IC share in high-end smartphone brands globally, but China-based vendors have been catching up in total shipments.
According to data from Sunrise Display & Touch, as of November 2013 Synaptics, FocalTech and Goodix ranked among the top three by monthly shipments. In addition to legacy vendors such as Atmel, Yilong and Cypress, newer vendors including Xunjun, Awinic, Qijing, Beilaite, Novatek, Jichuang Beifang, Meifasi, Lianyang, Silicon Creation, and Yili maintain shipments at KK-level, and the touch IC market is expected to see fierce competition in 2014.
Segment strategies and cost pressures
International vendors tend to focus on the high-end segment, leveraging advantages in brand, technology and capital. Some vendors concentrate on the mid- to low-end market and have started to introduce In-cell products to penetrate higher tiers. Other vendors, supported by specific platform partners and using package-on-board (COB) technology, mainly serve smaller phone brands and system houses. As cost reduction demands from smaller handset makers have increased, and single-finger usage is common among consumers, lower-cost single-finger plus gesture solutions have filled the market gaps caused by shortages from some vendors in 2013.
In the broader chip market, it is rare for a single chip to be priced above $1, but touch ICs have commanded prices of $3–$5 per chip, with a few vendors pricing above $5. By the second half of 2013, increased competition from new entrants and changing market capacity among the top three vendors led to price declines, and the industry expected overall prices to fall by 20–30% in 2014.
Design trends: reducing cost and shifting functions
With rapid growth of sub-1,000-yuan low- to mid-range smartphones in China during 2013, handset makers have intensified cost control. Low penetration of touch-screen notebooks has also pushed laptop vendors to seek lower-cost touch panel solutions. Throughout 2013, delivering better user experience at lower cost became a common goal for touch IC vendors. To save ITO, film, and shielding material costs and simplify production, demand increased for multi-touch solutions using single-layer ITO (G1F). Some vendors reduced costs further by eliminating Flash or even the MCU in the traditional single-chip sensor+MCU architecture.
Traditional capacitive touch-controller chips typically use a single-chip solution composed of a sensor detection module plus an MCU with embedded Flash, integrating touch recognition, coordinate calculation, pinch/zoom and other algorithms. As smartphone platform processing power has increased, with main application processors from MTK and Spreadtrum reaching clock rates above 1 GHz and with dual- and quad-core CPUs available, it has become feasible to move touch-data computation to the application processor, making the embedded MCU+Flash in the traditional architecture appear redundant.
Interference challenges with thin touch solutions
As on-cell and in-cell thin touch solutions become more common, direct bonding of touch modules to the LCD panel makes interference from the display panel and chargers increasingly severe. To improve interference immunity, Cypress released the TrueTouch Gen5 touch IC, which increased LCD scanning speed and bolstered interference protection. The device supports industry peak voltages up to 40 Vpp and adaptive frequency hopping (AFH) capable of locking onto charger noise frequencies in the 1–500 kHz range to provide improved power-supply noise immunity. However, this approach, while effective against interference, leads to higher instantaneous power consumption, and power consumption remains a primary concern for touch ICs.
Sensitivity versus noise immunity trade-offs
Lower power also means lower signal amplitude and therefore weaker interference resistance. Balancing sensitivity and interference immunity requires engineering effort. Synaptics ClearPad 3400 has been noted for reducing touch response latency while significantly improving signal-to-noise ratio (SNR) and strengthening resistance to LCD and charger interference. The ICN85 series from Jichuang Beifang uses a proprietary narrow-band filter technique with a finely controllable drive frequency at 1 kHz, greatly enhancing interference suppression and achieving performance comparable to leading international products, with overall behavior and customer experience reportedly superior to many mainstream competitors in China.
Different input modes impose different sensitivity requirements: active-pen and glove touch require higher sensitivity, while finger touch benefits from lower sensitivity. Smooth switching between these modes is a recognized industry challenge. The ICN85 series claims innovations across noise suppression, frequency-hopping operation, algorithms and power consumption, with processing performance that reportedly exceeds widely used domestic chips, addressing use cases such as waterproof operation, hover detection, glove use, proximity sensing and wide temperature swings.
Wearables and curved displays
As wearable devices grow in popularity, touch requirements diverge from those of phones and tablets. Curved screens require algorithms different from planar touch. The ICN85 series also targets wearables with power-optimized designs and touch algorithms for curved surfaces. High SNR and algorithms designed for curved panels aim to maintain accurate coordinate calculation even when the finger contact area changes continuously on an arc, with claimed center-coordinate deviation within 1 mm.
New interaction methods: HotKnot
MTK and Goodix collaborated to introduce HotKnot, a solution that uses the touch controller as the primary sensing medium and supplements data transfer with an optical sensor (P sensor) and an accelerometer (G sensor). When two devices equipped with HotKnot-capable touchscreens contact each other, they can exchange data and support payments without additional hardware cost, presenting an alternative to NFC. This feature has been adopted in certain phone and notebook models. Major internet companies Tencent and Alibaba have indicated interest in HotKnot for new interaction experiences and potential business opportunities.
