STV9211 datasheet(18/37 Pages) STMICROELECTRONICS

18 / 37 page

Functional description

STV9211

18/37

2.14

CRT cathode, DC-coupling mode (Figure 12)

The STV9211 can be used in DC coupling mode only.

The cut-off (InfraBlack) adjustment is done by the preamplifier.

The infra-black level (Vib) is adjusted independently for each channel via the Registers 10, 11 and

12 (see the complete description in

Section 2.10 ).

2.15

Preamplifier stand-by mode

The STV9211 is set in stand-by mode either by I2C or by decreasing the VCCP supply voltage.

I2C: the STV9211 is in stand-by mode when Register 13, bit 7=1

VCCP: the STV9211 is in stand-by mode when VCCP<3 V

In stand-by mode, the analog blocks are internally switched-off while the logic parts (I2C bus and

power-on reset) are still supplied.

The power consumption is below 20mW.

2.16

Amplifier stand-by mode

The STV9211 can set in stand-by mode any ST video amplifier with the CTL control pin.

When Register 9, bit 7=1, the AMPCTL pin is switched to low level (<0.3V). The amplifier is set in

stand-by mode when CTL<0.3V.

If not used, the AMPCTL pin must be connected to ground.

Figure 12: DC-coupling mode

OUT

Amplifier

STV95xx

STV9211

InfraBlack Adjustment

* Adjustment: 8-bit

* Range: 1.3 & 1.8V

* Offset: 3-bit

(Cut-off)

STV9211 数据表(PDF) 18 Page - STMicroelectronics