CDB44L11 - Cirrus Logic, Inc.

Cirrus Logic, Inc. 2004

http://www.cirrus.com

CDB44L11

Eval ua tion Bo ard for the CS4 4L 11

Features



23 mW/Channel into 16 Ω at 2.4 V



Variable power supplies from 1.8 V to 2.4 V



Digital bass boost and treble boost



Programmable digital volume control



Short circuit protection



>90% amplifier efficiency

Description

The CDB44L11 is an excellent means to quickly demon-

strate the CS44L11 Cirrus Digital Power Headphone

Amplifier IC. Analysis requires only a digital signal

source and an analog signal analyzer.

As shown below, the CS44L11 takes PCM digital audio

input and converts it to a PWM output. This 16-pin

TSSOP IC provides volume up/down, treble boost, bass

boost and mute functions via push buttons and a micro

controller using an I²C interface. A RS232 interface is

provided for programming the micro controller.

The CS8420 is a receiver and sample rate converter. It

takes in the S/PDIF at a range of input sample rates and

generates a PCM output signal at a fixed sample rate.

The low pass filter removes high frequency components

from the output PWM signal effectively converting it from

digital to analog.

ORDERING INFORMATION

CDB44L11 Demonstration Board

CS8420

S/PDIF IN CS44L11

I2S

Clock

Divider

MCLK

LRCK

and

SCLK

I2C

Control

Buttons 8

Low Pass

Filter

Low Pass

Filter

16 Ω

Headphones

LED Indicators

APR ‘04

DS640DB1

CDB44L11
2DS640DB1
TABLE OF CONTENTS
1.  CDB44L11 SYSTEM OVERVIEW  ............................................................................................ 3
2.  SCHEMATIC DESCRIPTIONS  ................................................................................................. 3
2.1 CS44L11 Headphone Monitor and Output Filter ................................................................ 3
2.2 Clocking  ............................................................................................................................. 4
2.3 CS8420 Sample Rate Converter  ....................................................................................... 4
2.4 Microcontroller  ................................................................................................................... 4
2.5 Power Supplies and Level-Shifting  .................................................................................... 4
3.  OPERATION INFORMATION ................................................................................................... 6
3.1 Operating Instructions ........................................................................................................ 6
4.  CONTROL FUNCTIONS ........................................................................................................... 7
4.1 Control Buttons  .................................................................................................................. 7
4.2 LED Status ......................................................................................................................... 7
4.3 CS44L11 Initialization  ........................................................................................................ 9
5.  BILL OF MATERIALS   ........................................................................................................... 17
6.  REVISION HISTORY  .............................................................................................................. 20
LIST OF FIGURES
Figure 1. CS44L11 PWM Headphone Amplifier............................................................................ 10
Figure 2. CS8420 S/PDIF Receiver and Sample Rate Converter................................................. 11
Figure 3. Microcontroller................................................................................................................ 12
Figure 4. Power Supply................................................................................................................. 13
Figure 5. Assembly Drawing ......................................................................................................... 14
Figure 6. Top Layer ....................................................................................................................... 15
Figure 7. Bottom Layer.................................................................................................................. 16
LIST OF TABLES
Table 1. Volume Status LED Decodes............................................................................................ 8
Table 2. Treble/Bass Boost Status LED Decodes........................................................................... 8
Table 3. Initial CS44L11 Register Settings......................................................................................9
Table 4. Revision History .............................................................................................................. 20

CDB44L11

DS640DB1 3

1. CDB44L11 SYSTEM OVERVIEW

The CDB44L11 is an excellent means of quickly demonstrating the CS44L11. The CS8420 dig-

ital audio interface receiver provides an interface to digital audio sources including the majority

of digital audio test equipment.

2. SCHEMATIC DESCRIPTIONS

2.1 CS44L11 Headphone Monitor and Output Filter

The CS44L11, shown in Figure 1, can accept sampling frequencies varying from 8 kHz to 96 kHz

and can produce a PWM frequency ranging from 8 X Fs to 48 X Fs (refer to CS44L11

datasheet). In this design the 8 X Fs mode is used with a 48.25 kHz sample frequency (Fs),

which will result in a 386 kHz PWM switching frequency.

As shown in Figure 1, L3, L4, C29, and C30 form the 2nd order low pass LC filter for the output

audio. The following equations show how to calculate the filter values:

Cfilter = 0.707 / (6.283 * fc *RL)

Lfilter = (1.414 * RL) / (6.283 * fc)

where:

fc = desired -3 dB frequency of the filter

RL = the nominal speaker load impedance

If you choose fc = 35 kHz, RL= 16 W, then:

Cfilter = 0.707 / (6.283 * 35000 * 16) = 0.2009 µF

Lfilter = (1.414 * 16) / (6.283 * 35000) = 102.881 µH

Choosing practical component values:

Cfilter = 0.22 µF

Lfilter = 100 µH

Output distortion is directly related to the inductor quality. The inductors should have a saturation

current of at least 150 mA for RL= 16 Ω. This design uses the Central Technologies CTGSR74B

100 µH inductors for the output filter. 220 µF capacitors are used to block any DC signal from

being heard at the output. For maximum output power, low ESR capacitors should be used on

the output.

CDB44L11

4DS640DB1

2.2 Clocking

The provided MCLK oscillator frequency is 12.352 MHz. Any oscillator between 6.4 MHz and

24.576 MHz may be used in the socket. The MCLK signal is divided by the clock divider to pro-

duce SCLK (MCKL/4), and LRCK (MCKL/256). Using a 12.352 MHz MCLK, SCLK is 3.088 MHz,

and LRCK is 48.25 kHz.

2.3 CS8420 Sample Rate Converter

Refer to Figure 2. The CS8420 is a S/PDIF receiver and sample rate converter. It is configured

to accept data at any sample rate between 32 kHz and 96 kHz and transmits data in PCM audio

data format based on the MCLK oscillator frequency. The CS8420, while not required, improves

system performance by reducing clock jitter and providing one fixed output frequency. In this de-

sign, the 48.25 kHz sample rate was chosen so that the CS8420 does not perform 1:1 conversion

when receiving 48 kHz input data. Noise can be introduced into the system when a 1:1 conver-

sion is performed and should be avoided for optimal performance. For more information please

refer to the CS8420 datasheet.

2.4 Microcontroller

Figure 3 shows the host microcontroller circuitry. There are 8 buttons for control features, 5 LEDs

to indicate status, and an I2C interface to the CS8420 and the CS44L11. See Table 3 for the ini-

tial CS44L11 register settings. After power is first applied to the board or the reset button is

pressed, all settings will revert to the default settings.

The board is populated with a Motorola MC68HC908GP32 with the software preprogrammed to

run the CDB44L11. The microcontroller code was written in C and compiled with the 'COSMIC

C Compiler'.

The microcontroller uses the I2C control bus to read and write to the CS44L11 control registers

- refer to CS44L11 data sheet for more information.

2.5 Power Supplies and Level-Shifting

Figure 4 shows the power supply and level shifting circuitry. Due to the CS44L11 operating at

below +5.0 V, level-shifting circuitry has been included to allow for operation with the microcon-

troller and the CS8420, both of which must run at +5.0 V.

The CS44L11 uses a half bridge output stage and is therefore affected by power supply pumping.

Power supply pumping is a phenomenon observed in half-bridge switching amplifiers. It is

caused by stored energy in the output inductor that is fed back into the power supply during

switching. To compensate for power supply pumping, a resistive load is used to dissipate the

CDB44L11

DS640DB1 5

switching current. In most designs this may be omitted due to other system components loading

the supply line and dissipating the current. The resistive load is only used to simulate a circuit

load.

In the CS44L11, the output MOSFETs directly switch between ground and VA_HP, therefore the

performance of the audio output from the amplifier is adversely affected any disturbance on the

power rails. To get the best performance power supply characteristics and power supply de-cou-

pling are critical.

Dynamic Range will be affected by switching noise. To reduce switching noise large value power

supply bypass capacitors must be used. This circuit uses a 0.1 µF and 1.0 µF ceramic capacitor

as well as a 100 µF low ESR tantalum capacitor between the VA_HP supply rail and ground. Op-

timally these should be placed as close to the CS44L11 pins 12 and 13 as possible. If a DC-DC

converter is used in the system its switching frequency should be locked to the CS44L11 PWM

switching frequency to reduce switching noise.

Power supply source impedance has a direct affect on the output distortion. A DC-DC converter

is a very low impedance source and will offer the best THD+N performance. Using a linear power

supply offers the next lowest impedance, while running directly from batteries to the VA_HP pins

offers the highest impedance and therefore the highest distortion.

A 47 µH inductor (L1) is used on the digital power supply of the CS44L11 to suppress noise. This

may be omitted if system noise is not an issue in your design.

CDB44L11

6DS640DB1

3. OPERATION INFORMATION

3.1 Operating Instructions

1) Connect an optical or coaxial S/PDIF signal to the S/PDIF input (OPT1 or J5).

2) Connect the output to either headphones or an analog analyzer. If using the RCA test jacks

(J8 and J9) a 16 Ω dummy load is provided in circuit. If using the headphone jack (J3) please

use a 16 Ω dummy load or 16 Ω headphones.

3) Verify that all power supplies are turned off and:

a. Connect +5.0 V to the terminal marked +5 V (J4).

b. Connect from +1.8 V to +2.4 V to the terminal marked VD_HP (J6).

c. Connect from +1.8 V to +2.4 V to the terminal marked VA_IN (J7).

d. Connect the power supply common ground to the terminal marked GND.

e. Verify that all power supply output voltages are set correctly to correspond to the setting

on the CDB44L11 and apply power to the board.

4) Once power is applied the volume LEDs will illuminate. Adjust settings as required with but-

tons - note that the volume, bass, and treble buttons do not 'ramp' and must be pushed for

each increment/decrement. The volume level will initialize at -24 dB.

CDB44L11

DS640DB1 7

4. CONTROL FUNCTIONS

4.1 Control Buttons

The function of the Control Buttons (Tables 1 and 2) is as follows:

•

Volume Up

- Adds 1 dB to current volume setting.

•

Volume Dn

- Subtracts 1 dB from current volume setting.

•

Treble Up

- Adds 1 dB to current treble setting.

•

Treble Dn

- Subtracts 1 dB from current treble setting.

•

Bass Up

- Adds 1 dB to current bass setting.

•

Bass Dn

- Subtracts 1 dB from current bass setting.

•

Mute

- Mutes audio and sets PWM to modulated 50% duty cycle.

•

Reset

- Upon release of the RESET Button, the microcontroller loads the default settings from the

flash memory into RAM. The RST line is pulled HI and these default settings are written to the

CS44L11 and the CS8420.

4.2 LED Status

The CDB44L11 has 5 LEDs (D20 - D24) to indicate volume, tone and mute settings and 1 fault

LED (D25). The LED readout will normally indicate the volume level per Table 1. When one of the

Treble Up/Down or Bass Up/Down buttons is pressed, the LEDs will show the Treble Boost or

Bass Boost setting as depicted in Table 2. When the button is released the LEDs will continue to

show the Treble/Bass Boost setting for a period of 2 seconds and will then return to indicating the

volume setting. In Table 1 and Table 2, a “1” indicates that the LED is lit up.

The MUTE button toggles operation between mute and un-mute. When the amplifier is muted the

LEDs flash at a 0.5 Hz rate.

D25 (LED near the CS8420 Receiver) indicates when there is a loss of input signal or any other

problem in the receiver.

CDB44L11

8DS640DB1

Volume

[dB]

LED Pattern

D20 D21 D22 D23 D24

+12 11111

+11 11110

+10 11101

+9 11100

+8 11011

+7 11010

+6 11001

+5 11000

+4 10111

+3 10110

+2 10101

+1 10100

0 10011

-1 10010

-2 10001

-3 10000

-4 01111

-5 01110

-6 01101

-7 01100

-8 01011

-9 01010

-10 01001

-11 01000

-15 to -1200111

-18 to -1600110

-21 to -1900101

-24 to -2200100

-32 to -2500011

-36 to -3300010

-42 to -3700001

-48 to -4300000

Table 1. Volume Status LED Decodes

Treble

or Bass

Boost

[dB]

LED Pattern

D20 D21 D22 D23 D24

0 11111

1 11110

2 11101

3 11100

4 11011

5 11010

6 11001

7 11000

8 10111

9 10110

10 10101

11 10100

12 10011

Table 2. Treble/Bass Boost Status LED Decodes

CDB44L11

DS640DB1 9

4.3 CS44L11 Initialization

Table 3 shows the CS44L11 register settings at startup. Refer to the CS44L11 Data Sheet for

more information.

Addr Function 7 6 5 4 3 2 1 0

2h Power and Muting

Control

SZC1 SZC0 PDN FLT RUPBYP RDNBYP Reserved Reserved

default10100000

3h Channel A

Volume Control

VOLA7 VOLA6 VOLA5 VOLA4 VOLA3 VOLA2 VOLA1 VOLA0

default11101000

4h Channel B

Volume Control

VOLB7 VOLB6 VOLB5 VOLB4 VOLB3 VOLB2 VOLB1 VOLB0

default00000000

5h Tone Control BB3 BB2 BB1 BB0 TB3 TB2 TB1 TB0

default00000000

6h Mode Control 1 BBCF1 BBCF0 TBCF1 TBCF0 TC1 TC0 TC_EN LIM_EN

default00000010

7h Limiter Attack Rate ARATE7 ARATE6 ARATE5 ARATE4 ARATE3 ARATE2 ARATE1 ARATE0

default00010000

8h Limiter Release Rate RRATE7 RRATE6 RRATE5 RRATE4 RRATE3 RRATE2 RRATE1 RRATE0

default00100000

9h Volume and Mixing

Control

IS1 IS0 RMP_SP1 RMP_SP0 ATAPI3 ATAPI2 ATAPI1 ATAPI0

default00001001

Ah Mode Control2 MCLKDIV CLKDV1 CLKDV0 DBS FRQSFT1 FRQSFT0 DEM1 DEM0

default00000000

Bh Mode Control 3 DIF1 DIF0 A=B VCBYP CP_EN FREEZE Reserved Reserved

default00101000

Ch Revision Indicator Reserved Reserved Reserved Reserved REV3 REV2 REV1 REV0

default 0 0 0 0 Read Only Read Only Read Only Read Only

Table 3. Initial CS44L11 Register Settings

CDB44L11

10 DS640DB1

Figure 1. CS44L11 PWM Headphone Amplifier

CDB44L11

DS640DB1 11

Figure 2. CS8420 S/PDIF Receiver and Sample Rate Converter

CDB44L11

12 DS640DB1

Figure 3. Microcontroller

CDB44L11

DS640DB1 13

Figure 4. Power Supply

CDB44L11

14 DS640DB1

Figure 5. Assembly Drawing

CDB44L11

DS640DB1 15

Figure 6. Top Layer

CDB44L11

16 DS640DB1

Figure 7. Bottom Layer

CDB44L11

DS640DB1 17

5. BILL OF MATERIALS

Item Rev Description Qty Reference Designator MFG MFG P/N

1 A CAP 1 µF 10% 16V X7R 0805 9 C1 C15 C56 C60 C66

C67 C68 C69 C70

KEMET C0805C105K4RAC

2 A CAP 220 µF 10% 6V TANT CASE D 2 C2 C3 KEMET T491D227K006AS

3 A CAP 0.01 µF 10% 50V X7R 0805 2 C5 C61 KEMET C0805C103K5RAC

4 A CAP 100 µF 20% 6.3V TANT CASE C 0 C6 VISHAY SPRAGUE 595D107X06R3C2T

5A CAP 0.1 µF 10% 50V X7R 0805 16 C8 C9 C10 C11 C20 C22

C24 C25 C26 C47 C55

C57 C63 C64 C65 C71

KEMET C0805C104K5RAC

6A CAP 0.1 µF 10% 50V X7R 0805 0 C12 C16 KEMET C0805C104K5RAC

7 A CAP 0.33 µF 10% 16V X7R 0805 0 C13 C17 KEMET C0805C334K4RAC

8 A CAP, 100 µF 20% 6.3V TANT CASE C 1 C14 VISHAY SPRAGUE 595D107X06R3C2T

9 A CAP 0.33 µF 10% 16V X7R 0805 1 C18 KEMET C0805C334K4RAC

10 A CAP 4700 pF 5% 50V C0G 1206 1 C19 KEMET C1206C472J5GAC

11 A CAP 47 µF 20% 16V ELEC CASE C 2 C21 C23 PANASONIC ECEV1CA470WR

12 A CAP 1 µF 10% 25V X7R 1206 1 C27 KEMET C1206C105K3RAC

13 A CAP 0.22 µF 10% 50V X7R 1206 2 C29 C30 KEMET C1206C224K5RAC

14 A CAP 1000 pF 5% 50V X7R 0603 1 C32 KEMET C0603C102J5RAC

15 A CAP 33 pF 10% 50V C0G 0805 2 C52 C53 KEMET C0805C330K5GAC

16 A CAP 0.033 µF 10% 50V X7R 0805 1 C54 KEMET C0805C333K5RAC

17 A CAP 0.01 µF 5% 50V X7R 0805 1 C58 KEMET C0805C103J5RAC

18 A LED CLR GRN, 2.1V 1mA .16MCD, SMD 5 D20 D21 D22 D23 D24 CHICAGO MINIATURE CMD28-21VGC/TR8/T1

19 A LED CLR SRED, 1.7V 1mA 1.6MCD, SMD 1 D25 CHICAGO MINIATURE CMD28-21SRC/TR8/T1

20 A WIRE, JUMPER 2P, 0.1””CTR, BRASS 5 GNDTP1 GNDTP2

GNDTP3 GNDTP4

GNDTP5

COMPONENTS COR-

PORATION

TP-101-10

21 A CONN, TEST PT, .1””CTR TIN PLATE BLK 2 HP_A HP_B KEYSTONE 5001

22 A CONN, BPOST 2”” SILV, NYLON INS, BLK 1 J1 JOHNSON COMPO-

NENTS

111-0103-001

23 A HDR 6x2, MLE .1””CTR, S GLD 0 J2 SAMTEC TSW-106-07-G-D

24 A JACK STEREO HEADPHONE 1 J3 A/D ELECTRONICS 3056-50

25 A CONN, BPOST 2”” SILV, NYLON INS, RED 1 J4 JOHNSON COMPO-

NENTS

111-0102-001

CDB44L11

18 DS640DB1

26 A JACK RCA, RA-BLK, PHONO, GLD TABS 3 J5 J8 J9 A/D ELECTRONICS ARJ-2018-NIL-1-NIL

27 A CONN, BPOST 2”” SILV, NYLON INS, GRN 1 J6 JOHNSON COMPO-

NENTS

111-0104-001

28 A CONN, BPOST 2”” SILV, NYLON INS, BLU 1 J7 JOHNSON COMPO-

NENTS

111-0110-001

29 A CONN, DE9 FMLE, RT. ANGL 1 J10 ADAM TECH DE09-SL-24

30 A HDR 3x1, MLE .1””CTR, S GLD 1 J11 SAMTEC TSW-103-07-G-S

31 A HDR 3x1, MLE .1””CTR, S GLD 0 J14 SAMTEC TSW-103-07-G-S

32 A IND 47 µH, 10%, 1210 2 L1 L8 PANASONIC ELJFA470KF

33 A IND 100 µH 20% CTGSR74B SERIES SM 2 L3 L4 CENTRAL TECHNOL-

OGIES

CTGSR74B-101M

34 A IND 220 µH 20% CTGS54 SERIES SM 0 L5 CENTRAL TECHNOL-

OGIES

CTGS54-220M

35 A IND 4.7 µH 10% 0805 1 L9 PANASONIC ELJFD4R7KF

36 A CONN, TEST PT, .1””CTR TIN PLATE BLK 0 LRCK MCLK SCLK

SDIN

KEYSTONE 5001

37 A OPTICAL RCVR, 6Mb/s, 7V 20MA 10M 1 OPT1 TOSHIBA TORX173

38 A TRAN, MOSFET nCHAN 750mA 20V SOT-23 1 Q1 MOTOROLA MGSF1N02ELT1

39 A RES 2.2k OHM 1/8W 5% 0805 FILM 7 R1 R5 R61 R62 R63

R64 R65

DALE CRCW0805222J

40 A RES 1k OHM 1/16W 1% 0603 FILM 1 R2 DALE CRCW06031001F

41 A RES 16 OHM 1/8W 5% 0805 FILM 2 R3 R17 DALE CRCW0805160J

42 A RES 5.1k OHM 1/8W 5% 0805 FILM 1 R4 DALE CRCW0805512J

43 A RES 0 OHM 1/8W 1% 1206 FILM 0 R6 R7 DALE CRCW1206000Z

44 A RES 51.1k OHM 1/16W 1% 0603 FILM 0 R8 DALE CRCW06035112F

45 A RES 10k OHM 1/16W 1% 0603 FILM 2 R9 R18 DALE CRCW06031002F

46 A RES 0 OHM 1/8W 1% 1206 FILM 1 R10 DALE CRCW1206000Z

47 A RES 1.62k OHM 1/16W 1% 0603 FILM 1 R11 DALE CRCW06031621F

48 A RES 0 OHM 1/10W 1% 0805 FILM 1 R12 DALE CRCW0805000Z

49 A RES 10k OHM 1/8W 5% 0805 FILM 3 R14 R59 R68 VISHAY CRCW0805103J

50 A RES 1 OHM 1/8W 5% 1206 FILM 1 R15 DALE CRCW12061R0J

51 A RES 158k OHM 1/16W 1% 0603 FILM 0 R16 DALE CRCW06031583F

52 A RES 432k OHM 1/16W 1% 0603 FILM 0 R19 DALE CRCW06034323F

Item Rev Description Qty Reference Designator MFG MFG P/N

CDB44L11

DS640DB1 19

53 A RES 191k OHM 1/16W 1% 0603 FILM 0 R20 DALE CRCW06031913F

54 A RES 137k OHM 1/16W 1% 0603 FILM 0 R21 DALE CRCW06031373F

55 A RES 69.8k OHM 1/16W 1% 0603 FILM 2 R22 R24 DALE CRCW06036982F

56 A RES 240 OHM 1/8W 5% 1206 FILM 2 R23 R25 DALE CRCW1206241J

57 A RES POT 500K 10%10TURN TOP-ADJ TH 0 R26 BOURNS 3266W-1-504

58 A RES 10M OHM 1/10W 1% 0805 FILM 1 R57 DALE CRCW08051005F

59 A RES 330k OHM 1/8W 5% 0805 FILM 1 R58 DALE CRCW0805334J

60 A RES 33 OHM 1/8W 5% 0805 FILM 3 R66 R67 R78 PANASONIC ERJ6GEYJ330V

61 A RES 75 OHM 1/10W 1% 0805 FILM 1 R76 DALE CRCW080575R0F

62 A SWITCH 0/1 TACT, W/ESD 8 S1 S2 S3 S4 S5 S6 S7

C&K PTS645TL50

63 A IC, DIGITAL PWM HEADPHONE MONITOR,T 1 U1 CIRRUS LOGIC CS44L11-KZ/A

64 A IC LOG 8-BIT W/3-ST OUT REG SOIC16 1 U2 TEXAS INSTRU-

MENTS

SN74HC590AD

65 A IC LIN H-CUR L-NOISE CNVTR SSOP16 0 U3 MAXIM MAX1706EEE

66 A IC LOG, INVERT, 5P, UHS TINY, SOT23 2 U4 U20 FAIRCHILD SEMI-

CONDUCTOR

NC7SZ04M5X

67 A IC LOG, 4 BUF W/3ST 14P TSSOP 2 U5 U6 FAIRCHILD SEMI-

CONDUCTOR

74VHC125MTC

68 A IC PGM, mCNTR 32K PQFP44 1 U17 MOTOROLA MC68HC908GP32CFB

69 A IC LNR 5V MCH RS-232 DRV/RCV SOIC16 1 U18 MAXIM MAX232CWE

70 D1 IC CRUS DIG AUD SAMP RTE CNV SOIC28 1 U23 CRYSTAL SEMICON-

DUCTOR

CS8420-CS/D1

71 A SPCR, STANDOFF 4-40 THR, 0.875””L 4 X1 X2 X3 X4 KEYSTONE 1809

72 A OSC 32.768KHZ 20ppm 8mm x 3.8mm SMT 1 Y1 CITIZEN CM200S32.768KDZFT

73 A OSC 12.352MHZ 50PPM 5V FULL DIP14 1 Y2 CAL CRYSTAL CX21AF-12.3520MHZ

74 A DIODE, SCHTKY POWER RECT, SOD123 0 Z2 MOTOROLA MBR0520LT1

75 A DIODE TRANS. SUPPRESSOR, 6.8V, 600W 3 Z3 Z4 Z5 MOTOROLA P6KE6.8

76 D CONN, SHUNT, 2P, .1””CTR, BLK 3 XJ2,XJ11,XJ14 MOLEX 15-29-1025

Item Rev Description Qty Reference Designator MFG MFG P/N

CDB44L11

20 DS640DB1

6. REVISION HISTORY

Release Date Changes

DB1 April 2004 Initial Release

Table 4. Revision History

Contacting Cirrus Logic Support

For all product questions and inquiries contact a Cirrus Logic Sales Representative.

To find the one nearest to you go to

www.cirrus.com

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