WM8770 datasheet(50/52 Pages) WOLFSON

Part #	WM8770

Description	24-bit, 192kHz 8-Channel Codec with Volume Control

PDF	52 Pages

Scroll/Zoom	100%

Manufacturer	WOLFSON [Wolfson Microelectronics plc]

Direct Link	http://www.wolfsonmicro.com

Logo

50 / 52 page

WM8770

Production Data

PD Rev 4.1 June 2005

It is recommended that a lowpass filter be applied to the output from each DAC channel for Hi Fi

applications. Typically a second order filter is suitable and provides sufficient attenuation of high

frequency components (the unique low order, high bit count multi-bit sigma delta DAC structure used

in WM8770 produces much less high frequency output noise than competitors devices). This filter is

typically also used to provide the 2x gain needed to provide the standard 2Vrms output level from

most consumer equipment. Figure 24 shows a suitable post DAC filter circuit, with 2x gain.

Alternative inverting filter architectures might also be used with as good results.

Figure 41 Recommended Post DAC Filter Circuit

7.5k

Ω

1.8k

Ω

10uF

1.0nF

47k

Ω

4.7k

Ω

680pF

4.7k

Ω

OP_FIL

VOUT1L

OP_FIL

VOUT1R

OP_FIL

VOUT2R

OP_FIL

VOUT2L

OP_FIL

VOUT3L

OP_FIL

VOUT3R

OP_FIL

VOUT4L

OP_FIL

VOUT4R

WM8770 Datasheet(PDF) 50 Page - Wolfson Microelectronics plc