12

LINE_IN_R

24

I

Right Line Input. The right line-level may be selected for recording via one of the stereo ADC’s via

the Input Mux. In addition, this input can be gained/attenuated from +12dB to -34.5dB in 1.5dB

steps and then summed with right line output (LINE_OUT_R).

CD_L

18

I

Left CD Audio Channel. This line-level input may be input to one of the stereo ADC’s via the Input

Mux. It can also be gained/attenuated from +12dB to -34.5dB in 1.5dB steps and then summed with

the Left Line Output (LINE_OUT_L).

CD_GND

19

I

CD Audio Analog Ground.

CD_R

20

I

Right CD Audio Channel. This line-level input is selected for input to one of the stereo ADCs via the

Input Mux. It can also be gained/attenuated from +12dB to -34.5dB in 1.5dB steps and then

summed with the Right Line Output (LINE_OUT_R).

VIDEO_L

16

I

Left Video Input. This line-level input is driven with the left channel audio track from a video source.

The signal is selected for input to one of the stereo ADCs via the Input Mux, and it can be gained/at-

tenuated from +12dB to -34.5dB in 1.5dB steps and then summed with Left Line Output

(LINE_OUT_L).

VIDEO_R

17

I

Right Video Input. This line-level input is driven with the right channel audio track from a video

source. The signal is selected for input to one of the stereo ADCs via the Input Mux, and it can be

gained/attenuated from +12dB to -34.5dB in 1.5dB steps and then summed with Right Line Output

(LINE_OUT_R).

AUX_L

14

I

Left Auxiliary Input. This line-level input is input to one of the stereo ADCs via the Input Mux. It can

also be gained/attenuated from +12dB to -34.5dB in 1.5dB steps and then summed with the Left

Line Output (LINE_OUT_L).

AUX_R

15

I

Right Auxiliary Input. This line-level input is input to one of the stereo ADCs via the Input Mux. It

can also be gained/attenuated from +12dB to -34.5dB in 1.5dB steps and then summed with the

Right Line Output (LINE_OUT_R).

LINE_OUT_L

35

O

Left Line Output. This line level output is the post-mixed output for the left audio channel. The audio out-

put passes through a Master Volume block that provides attenuation from 0dB to 45dB in 1.5dB steps.

LINE_OUT_R

36

O

Right Line Output. This line level output is the post-mixed output for the right audio channel. The

audio output passes through a Master Volume block that provides attenuation from 0dB to 45dB in

1.5dB steps.

MONO_OUT

37

O

Mono Output. This user selectable line level output is either the post-mixed output or the micro-

phone input. The mono output passes through a Mono Volume block that provides attenuation from

0dB to 45dB in 1.5dB steps.

MISCELLANEOUS

27

O

Voltage Reference. Nominal 2.25V reference output. Should not be used to sink or source current.

28

O

Voltage Reference Out. Nominal 2.25V reference output with 5mA drive capability. Intended a

microphone bias.

AFILT1

29

O

Anti-Alias Filter 1 (Left Record Channel). This pin requires a 1nF capacitor to analog ground for

proper operation.

AFILT2

30

O

Anti-Alias Filter 2 (Right Record Channel). This pin requires a 1nF capacitor to analog ground for

proper operation.

AFILT3

31

O

Anti-Alias Filter 3 (MIC Record Channel). This pin requires a 1nF capacitor to analog ground for

proper operation.

CAP1, CAP2

33, 34

O

Left Channel DC Blocking CAP. For proper operation connect a 1

µF capacitor between these two pins.

CAP3, CAP4

39, 40

O

Right Channel DC Blocking CAP. For proper operation connect a 1

µF capacitor between these

two pins.

XTL_IN

2

I

24.576MHz Crystal Input. Leave this pin unconnected when using an external clock source.

XTL_OUT

3

O

24.576MHz Crystal Output. This pin may also be used to input an external 24.576MHz clock

source.

25, 38

I

Analog Supply Voltage (5.0V).

AGND

26, 42

I

Analog Ground.

1, 9

I

Digital Supply Voltage (5.0V).

GND

4, 7

I

Digital Ground.

NAME

TQFP PIN

NUMBER

INPUT/

OUTPUT

DESCRIPTION

HMP9701