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AD73322L

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PIN FUNCTION DESCRIPTIONS

Mnemonic

Function

VINP1

Analog Input to the inverting input amplifier on Channel 1’s positive input.

VFBP1

Feedback Connection from the output of the inverting amplifier on Channel 1’s positive input. When the input

amplifiers are bypassed, this pin allows direct access to the positive input of Channel 1’s sigma-delta modulator.

VINN1

Analog Input to the inverting input amplifier on Channel 1’s negative input.

VFBN1

Feedback connection from the output of the inverting amplifier on Channel 1’s negative input. When the input

amplifiers are bypassed, this pin allows direct access to the negative input of Channel 1’s sigma-delta modulator.

REFOUT

Buffered Reference Output, which has a nominal value of 1.2 V or 2.4 V, the value being dependent on the status

of Bit 5VEN (CRC:7). As the reference is common to the two codec units, the reference value is set by the wired

OR of the CRC:7 bits in Control Register C of each channel.

REFCAP

A bypass capacitor to AGND2 of 0.1

µF is required for the on-chip reference. The capacitor should be fixed to

this pin.

AVDD2

Analog Power Supply Connection.

AGND2

Analog Ground/Substrate Connection2.

DGND

Digital Ground/Substrate Connection.

DVDD

Digital Power Supply Connection.

RESET

Active Low Reset Signal. This input resets the entire chip, resetting the control registers and clearing the digital

circuitry.

SCLK

Serial Clock Output whose rate determines the serial transfer rate to/from the codec. It is used to clock data or

control information to and from the serial port (SPORT). The frequency of SCLK is equal to the frequency of the

master clock (MCLK) divided by an integer number—this integer number being the product of the external mas-

ter clock rate divider and the serial clock rate divider.

MCLK

Master Clock Input. MCLK is driven from an external clock signal.

SDO

Serial Data Output. Both data and control information may be output on this pin and are clocked on the positive

edge of SCLK. SDO is in three-state when no information is being transmitted and when SE is low.

SDOFS

Framing Signal Output for SDO Serial Transfers. The frame sync is one bit wide and is active one SCLK period

before the first bit (MSB) of each output word. SDOFS is referenced to the positive edge of SCLK. SDOFS is in

three-state when SE is low.

SDIFS

Framing Signal Input for SDI Serial Transfers. The frame sync is one bit wide and is valid one SCLK period

before the first bit (MSB) of each input word. SDIFS is sampled on the negative edge of SCLK and is ignored

when SE is low.

SDI

Serial Data Input. Both data and control information may be input on this pin and are clocked on the negative

edge of SCLK. SDI is ignored when SE is low.

SE

SPORT Enable. Asynchronous input enable pin for the SPORT. When SE is set low by the DSP, the output

pins of the SPORT are three-stated and the input pins are ignored. SCLK is also disabled internally in order to

decrease power dissipation. When SE is brought high, the control and data registers of the SPORT are at their

original values (before SE was brought low); however, the timing counters and other internal registers are at

their reset values.

AGND1

Analog Ground/Substrate Connection.

AVDD1

Analog Power Supply Connection.

VOUTP2

Analog Output from the Positive Terminal of Output Channel 2.

VOUTN2

Analog Output from the Negative Terminal of Output Channel 2.

VOUTP1

Analog Output from the Positive Terminal of Output Channel 1.

VOUTN1

Analog Output from the Negative Terminal of Output Channel 1.

VINP2

Analog Input to the inverting input amplifier on Channel 2’s positive input.

VFBP2

Feedback connection from the output of the inverting amplifier on Channel 2’s positive input. When the input

amplifiers are bypassed, this pin allows direct access to the positive input of Channel 2’s sigma-delta modulator.

VINN2

Analog Input to the inverting input amplifier on Channel 2’s negative input.

VFBN2

Feedback connection from the output of the inverting amplifier on Channel 2’s negative input. When the input

amplifiers are bypassed, this pin allows direct access to the negative input of Channel 2’s sigma-delta modulator.