THC7984 参数 Datasheet PDF下载

THC7984_Rev.1.00_E

Functional Description

Digital Input

- All digital inputs are 5V tolerant during power-on.

Analog Input

- The THC7984 has two ports that each include three analog inputs for RGB or YPbPr. The input port can be selected by

register.

- In case input signals are YPbPr, Y may be input into GAIN0 (or GAIN1) and SOGIN0 (or SOGIN1) , Pr into RAIN0

(or RAIN1) , and Pb into BAIN0 (or BAIN1) .

- The THC7984 accommodates analog signals ranging from 0.5 Vpp to 1.0 Vpp.

Video Filter (LPF)

The THC7984 has 2 kinds of low-pass filters.

- 5th-order LPF for YPbPr, whose bandwidth is adjustable from 6 MHz to 92 MHz in 24 steps.

- 2nd-order LPF for RGB, whose bandwidth is adjustable in 4 steps (40 MHz, 90 MHz, 170 MHz, and 310 MHz) .

Serial Interface

- The THC7984 is controlled by 2-wire serial interface.

- Serial clock SCL supports up to 100 kHz.

Sync Input

- The THC7984 has two ports that each include two digital inputs for the separate sync (HSYNC and VSYNC) . The

input port can be selected by register.

- The THC7984 can process composite sync (CSYNC) . CSYNC may be input into HSYNC0 or HSYNC1.

Digital Output

- The digital outputs can operate from 2.5 V to 3.3 V (VDD) .

- The output drive strength is programmable by 2-bit registers (except SDA) .

Clamp

- Pedestal clamp for RGB and Y (luminance) clamps black level to 0 with automatic offset cancel.

- Midscale clamp for PbPr clamps to 512 with automatic offset cancel.

- 256-level clamp for Y (luminance) clamps to 256 with automatic offset cancel. It can be used for A/D conversion of Y

including sync signal. In this case, input signal needs to be attenuated to put it within the input rang of A/D converter.

- Clamp pulses can be input from CLAMP pin when external clamp is selected.

Gain, Offset

- Gain is programmable by 11-bit registers (2048 steps) .

- Offset from -256 to +255 can be added to the output code.

- Gain and offset can be adjusted independently.

Reference Voltage

- The THC7984 has Band Gap Reference inside and doesn’t require external voltage reference.

- The internal reference voltages (REFHI, REFCM, and REFLO) must be bypassed to stabilize. Each pin (REFHI,

REFCM, and REFLO) is connected to ground through a 10

μF

capacitor.

Copyright©2009 THine Electronics, Inc.

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THine Electronics, Inc.