Components

Semtech Filter Devices Protect High-Resolution LCD Screens On 3G Phones

Semtech Corp. announced the EClamp™237xK family of resistor-capacitor (R-C) protection devices with the low capacitance, high attenuation and low clamping voltage needed for high-resolution color LCD interfaces in GSM and CDMA-based 3G handsets.

The devices expand Semtech’s EMIClamp™ protection products portfolio by safeguarding lines from cellular frequencies between 1.8 to 2.5 GHz – the data rates required by the latest generation of high-resolution LCD screens used for visually oriented 3G handsets. The EClamp237xK series includes the four-line EClamp2374K, the six-line EClamp2376K and the eight-line EClamp2378K. These EClamp237xK devices have a very low C(in) value of 20pF, and together with a series resistance of 100±, they provide greater than 30dB attenuation for cell phone frequencies.

The EClamp237xK packages are narrow (1.3mm) and low profile (0.50mm) with a variable length depending on the number of lines supported. The flow-through design of the devices simplifies signal routing for a faster and more convenient layout. These parts feature a 400µ lead pitch saving up to 33% in board space compared to 500µ pitch parts, and with a height reduction of 14%, they enable filter protection in low-profile designs.

Each device in the family includes TVS diodes for electrostatic discharge (ESD) protection and an R-C network for electromagnetic interference (EMI) and radio frequency interference (RFI) filtering. The devices complement Semtech’s EClamp238xK series of resistor-capacitor (R-C) devices, giving designers more flexibility for protecting color LCD displays.

The EClamp237xK devices are available in the RoHS/WEEE-compliant Semtech Leadless Package (SLP), which offers the same small, low-profile design as "flip chip" alternatives, but with increased manufacturing durability. The high integration of the EClamp237xK devices replaces 32 discrete passive devices in a typical handset design, thus saving board space.

"While higher-resolution screens on handsets are enabling a wide range of new consumer services, they still remain a high EMI/ESD threat environment," said Rick Hansen, Semtech’s Director of Marketing for Protection Products. "This new product family gives manufacturers both the higher data rates they need for these LCDs as well as the low profile and small size that provides a lot of design flexibility for smaller handset form factors."

The EClamp2374K is priced at $0.25 each in 1,000-piece lots; the EClamp2376K is priced at $0.33 each in 1,000-piece lots; and the EClamp2378K is priced at $0.40 each in 1,000-piece lots.

Semtech Corp.
To Top