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AN248

Transitioning to the CS4344 family

David Olivenbaum

Applications Engineer

1. Introduction

This application note describes how to easily transition to the CS4344 family from an existing design

which uses the CS4334/5/8 or CS4340/40A. The CS4344 family was designed to give a simple transition

path from the CS4334 family or the CS4340/40A. Please refer to the CS4344 data sheet for supplemental

information and specifications concerning operation of the device. A brief comparison between the

product families is shown in Table 1.

The CS4344 family offers better analog performance (dynamic range and THD+N), a smaller package,

and is more cost effective than the CS4340A and CS4340. For users of the CS4334, the CS4344 family

is a simple, yet affordable, upgrade to higher performance.

2. The Design Transition

2.1 Transitioning from the CS4340/40A

2.1.1 Hardware changes

The CS4344 family removes six pins from the sixteen pins of the CS4340/40A. The CS4344 family also

uses a smaller lead pitch which takes up about 75% less space than the CS4340/40A.

Figure 1 is a modification of the Figure 2 schematic which helps show the changes between the

CS4340/40A and the CS4344. Figure 1 shows the schematic for the CS4344/5/6/8. Figure 2 shows

the original example schematic for the CS4340/40A.

CS4344 CS4340A CS4340 CS4334

Dynamic Range

105

101 101 96

THD+N

-95

-91 -91 -88

Resolution

bits

24 24 24

Sample Rate

kHz

192

192 96 96

Power Supply

3-5

3-5 3-5 5

Volume Control No

No No No

Auto Fs De tect Yes

Yes No No

Package 10TSSOP

16SOIC 16SOIC 8SOIC

Price (1K) $1.55

$2.15 $1.95 $1.35

Table 1. Product Comparison

DEC ‘03

AN248rev1

Summary of content (5 pages)

PAGE 1
AN248 Transitioning to the CS4344 family David Olivenbaum Applications Engineer 1. Introduction This application note describes how to easily transition to the CS4344 family from an existing design which uses the CS4334/5/8 or CS4340/40A. The CS4344 family was designed to give a simple transition path from the CS4334 family or the CS4340/40A. Please refer to the CS4344 data sheet for supplemental information and specifications concerning operation of the device.
PAGE 2
AN248 Figure 1. CS4344/5/6/8 Design Schematic Figure 2. CS4340/40A Design Schematic The changes made from Figure 2 to Figure 1 were as follows: 2 • Removed Q1, Q2, Q3, Q4, R7, and R8. • Deleted the nets RST, DIF1, DIF0, and DEM. • Changed C7 to10 µF, changed C10 to 3.3 µF, changed R3 and R5 to 470 Ω. • Replaced CS4340/40A with CS4344.
PAGE 3
AN248 • Note that the same C4 and C6 capacitors may be used. The following table shows the pin for pin mapping between the two part families: Pin Name CS4340/40A CS4344 family RST 1 SDATA > SDIN 2 1 SCLK > DEM/SCLK 3 2 LRCK 4 3 MCLK 5 4 DIF1 6 DIF0 7 DEM 8 FILT+ 9 6 VQ 10 5 REF_GND 11 AOUTB 12 10 AGND 13 8 VA 14 9 AOUTA 15 7 MUTEC 16 Table 2.
PAGE 4
AN248 2.2 Transitioning from the CS4334/5/8 2.2.1 Hardware changes The CS4344 family adds two filter pins (which require capacitors) to the eight pins of the CS4334 family. The CS4344 family also uses a smaller lead pitch which takes up about 50% less space than the CS4334 family. Figure 3 shows an example schematic for the CS4334. Figure 1 shows the modified new schematic for the CS4344 Figure 3.
PAGE 5
AN248 2.2.2 Functional Changes • The CS4344 supports the same internal SCLK mode for de-emphasis support as in the CS4334 family. • The part numbers for the CS4344 family were assigned to be congruent with those of the CS4334 family. The last digits of each variant in each family are the same for similar devices. This allows for an easy decision on which new part to use. Note that the CS4349 (18-bit RJ) is not available at this time. Ordering information is provided in the back of the CS4344 datasheet.