Ultra-Low-Power Video Buffer from STMicroelectronics Unlocks Extra Battery Life for Mobile Video Products

Mobile video devices including digital cameras, camera phones and personal media players can run longer using the new TSH122 video buffer IC from STMicroelectronics (NYSE: STM), one of the world leaders in analog ICs. The new device has a low operating current of 1.7mA and draws the lowest standby current among comparable devices, at just 4nA typical, 500nA maximum.

The TSH122 is a single-channel CVBS (Composite Video Baseband Signal) video buffer/filter with 6dB internal gain, optimized for DC or AC coupling to a 75-Ohm cable. The input can be directly connected to the video DAC, to drive composite video to an external device such as a TV display. Consistent with its low power consumption, operation from a single supply of 2.2Vto 5V (tested at 2.5V and 3.3V) also makes this device compatible with battery-powered applications.

By including a 6th-order reconstruction filter for attenuation of DAC sampling aliases, the TSH122 saves cost and board space. Internal gain-setting resistors further reduce component count and footprint. SAG correction is also implemented at the output, allowing the use of a smaller coupling capacitor. Achieving this high level of integration within the compact 2.2 x 2.4 mm SC70-6 (SOT323-6) package maximizes PCB space for designers to implement extra features or reduce end-product size.

Video-performance highlights for the TSH122 include differential gain of 0.5%, differential phase of 0.5 degrees, and low group delay of 10ns. Attenuation at 27MHz is typically better than –36dB, and the amplifier achieves gain flatness beyond 5.4MHz. Rail-to-rail output capability also maximizes dynamic range for low-voltage operation.

STMicroelectronics, www.st.com.