CS4202_05 Datasheet, PDF (61/66 Pages) Cirrus Logic – Audio Codec ’97 with Headphone Amplifier

CS4202
GPIO2 - General Purpose I/O, Input/Output, Pin 32
This pin is a general purpose I/O pin that can be used to interface with various external circuitry. When
configured as an input, it functions as a Schmitt triggered input with 350 mV hysteresis at 5 V and
220 mV hysteresis at 3.3 V. When configured as an output, it can function as a normal CMOS output
(4 mA drive) or as an open drain output. This pin powers up in the high impedance state for backward
compatibility.
GPIO3 - General Purpose I/O, Input/Output, Pin 33
This pin is a general purpose I/O pin that can be used to interface with various external circuitry. When
configured as an input, it functions as a Schmitt triggered input with 350 mV hysteresis at 5 V and
220 mV hysteresis at 3.3 V. When configured as an output, it can function as a normal CMOS output
(4 mA drive) or as an open drain output. This pin powers up in the high impedance state for backward
compatibility.
GPIO4/SDO2 - General Purpose I/O / Serial Data Output 2, Input/Output, Pin 34
This pin is a general purpose I/O pin that can be used to interface with various external circuitry. When
configured as an input, it functions as a Schmitt triggered input with 350 mV hysteresis at 5 V and
220 mV hysteresis at 3.3 V. When configured as an output, it can function as a normal CMOS output
(4 mA drive) or as an open drain output. This pin also provides the serial data for the second serial data
port when the SDO2 bit in the Serial Port Control Register (Index 6Ah) is ‘set’. This pin powers up in the
high impedance state for backward compatibility.
Power Supply Pins
DVdd1, DVdd2 - Digital Supply Voltage, Pins 1 and 9
Digital supply voltage for the AC-link section of the CS4202. These pins can be tied to +5 V digital or to
+3.3 V digital. The CS4202 and controller’s AC-link should share a common digital supply.
DVss1, DVss2 - Digital Ground, Pins 4 and 7
Digital ground connection for the AC-link section of the CS4202. These pins should be isolated from
analog ground currents.
AVdd1, AVdd2 - Analog Supply Voltage, Pins 25 and 38
Analog supply voltage for the analog and mixed signal section of the CS4202 (AVdd1) as well as the
headphone amplifier (AVdd2). These pins must be tied to the analog +5 V power supply. It is strongly
recommended that +5 V be generated from a voltage regulator to ensure proper supply currents and
noise immunity from the rest of the system.
AVss1, AVss2 - Analog Ground, Pins 26 and 42
Ground connection for the analog, mixed signal, and substrate sections of the CS4202 (AVss1) as well
as the headphone amplifier (AVss2). These pins should be isolated from digital ground currents.
DS549PP2
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