LC78833M/V Operation

1. Digital Filters

The LC78833M and LC78833V perform the computations shown in the figure.

• Oversampling

The oversampling circuit in these ICs consists of two 2

× interpolation filters (implemented as FIR filters)

connected vertically.

In particular, these ICs implement 4

× oversampling by the vertical connection of two FIR filter stages, a 33rd-order

stage and a ninth-order stage. See page 9 for the filter characteristics.

• De-emphasis

A first-order IIR filter is used for de-emphasis. The filter coefficients are optimized for a sampling frequency of

44.1 kHz. See page 9 for the filter characteristics when de-emphasis is applied.

— De-emphasis on/off switching

De-emphasis is on when the EMP pin is high.

De-emphasis is off when the EMP pin is low.

2. Digital Audio Data Input

These ICs handle digital audio data in a 16-bit two’s complement MSB first format. The 16-bit serial data is input to

an internal register from the DATA pin on BCLK rising edges and read in on rising and falling edges of the LRCK

signal.

No. 5212-6/11

LC78833M, 78833V