STMicroelectronics Releases Low-Power Video Buffer for Portable Consumer Devices
November 17, 2008 // Published as a news service by IHS
STMicroelectronics (ST) said mobile video devices including digital cameras, camera phones and personal media players can run longer using its new TSH122 video buffer integrated circuit (IC).
According to ST, the new device has a low operating current of 1.7 mA and draws the lowest standby current among comparable devices, at just 4 nA typical, 500 nA maximum.
The TSH122 is a single-channel composite video baseband signal (CVBS) video buffer/filter with 6 dB internal gain, optimized for direct current (DC) or alternating current (AC) coupling to a 75 Ohm cable.
The input can be directly connected to the video digital-to-analog converter (DAC) to drive composite video to an external device such as a TV display.
Operation from a single supply of 2.2 volts (V) to 5 V (tested at 2.5 V and 3.3 V) also makes this device compatible with battery-powered applications.
By including a sixth-order reconstruction filter for attenuation of DAC sampling aliases, the TSH122 saves cost and board space, ST said. Internal gain-setting resistors reduce component count and footprint.
Sag correction is also implemented at the output, allowing the use of a smaller coupling capacitor. Achieving this level of integration within the 2.2 millimeter by 2.4 millimeter SC70-6 (SOT323-6) package maximizes printed circuit board (PCB) space for designers to implement extra features or reduce end-product size, ST said.
Video-performance for the TSH122 includes differential gain of 0.5%, differential phase of 0.5 degrees and low group delay of 10 ns. Attenuation at 27 MHz is typically better than -36dB, and the amplifier achieves gain flatness beyond 5.4 MHz. Rail-to-rail output capability also maximizes dynamic range for low-voltage operation, ST said.
The TSH122 is in full production, and samples are also available.
Source: STMicroelectronics (ST).