CS4340A

6

DS590PP2

3. APPLICATIONS

3.1

Upgrading from the CS4340 to the CS4340A

The CS4340A is pin and functionally compatible with all CS4340 designs, operating at the standard audio

sample rates, that use pin 3 as a serial clock input. In addition to the features of the CS4340, the CS4340A

supports standard sample rates up to 192 kHz, as well as automatic mode detection for sample rates be-

tween 4 and 200 kHz. The automatic mode detection feature allows sample rate changes between single,

double and quad-speed modes without external intervention.

The CS4340A does not support an internal serial clock mode, sample rates between 50 kHz and 84 kHz or

de-emphasis for 32 and 48 kHz, as does the CS4340.

3.2

Sample Rate Range/Operational Mode Detect

The device operates in one of three operational modes. It will auto-detect the correct mode when the input

ple rates outside the specified range for each mode are not supported.

3.3

System Clocking

The device requires external generation of the master (MCLK), left/right (LRCK) and serial (SCLK)

MCLK according to specified ratios. The specified ratios of MCLK to LRCK, along with several standard

audio sample rates and the required MCLK frequency, are illustrated in Tables 2-4.

4 kHz - 50 kHz

Single-Speed Mode

84 kHz - 100 kHz

Double-Speed Mode

170 kHz - 200 kHz

Quad-Speed Mode

Table 1. CS4340A Auto-Detect