STV8247DSXT datasheet(43/149 Pages) STMICROELECTRONICS

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STV82x7

Power Supply Management

A mixed supply voltage environment requires the following voltages:

● 3.3V capable inputs/outputs for digital pins;

● 1.8V digital core;

● 8V capable inputs/outputs for analog audio interfaces (capability to output 2 VRMS for SCART

requirements);

● 3.3V for stereo ADC and DAC (analog part);

● 1.8V for stereo ADC and DAC (digital part);

● 1.8V for IF ADC and AGC.

These voltages will be delivered by the application with an accuracy of ±5%. For more information,

refer to Section 13.3: Power Supply Data.

Other specific DC voltages or features are provided:

● Voltage Reference and Biasing Generation (AGC, ADCs, DACs),

● Bandgap reference.

8.1

Standby Mode (Loop-through mode)

The STV82x7 provides a Loop-through mode configuration that bypasses IC functions via a SCART

I/O pin (Full Analog Path only). In this case, only a minimum power of 200 mW is required.

In Standby mode, the digital and analog power supplies are switched off, except for pins VCC_H,

VCC33_LS, VCC33_SC, and VCC_NISO which are used to maintain the SCART path with the last

configuration programmed by analog matrixing (register SCART1_2_OUTPUT_CTRL and

SCART3_OUTPUT_CTRL). When switching back to normal Full Power mode, all I²C registers are

reset except for those used in Standby mode to maintain the original configuration.

In Standby mode, the I²C bus does not operate. However, the bus can still be used by other ICs

since the I²C I/O pins (SDA and SCL) of the STV82x7 are forced into a high-impedance

configuration.

STV8247DSXT Datasheet(PDF) 43 Page - STMicroelectronics