ETC CE2766

CE2766
Microelectronics
6-Channel Audio DAC, 24-bit, 192kHz
DESCRIPTION
FEATURES
The CE2766 is a mixed signal CMOS monolithic audio
digital to analog converter. It contains six multi-bit sigma
delta DAC. The system consists of 128-time interpolation
filters, 4th order Σ∆ modulators, switch capacitors and
analog reconstruction filters. The one bit Σ∆ converter
offers superior differential linearity, with no distortion due
to component mis-match. high tolerance to clock jitter.
• Six Channel Audio DAC.
- 101 dB SNR (A Weighted).
- -86 dB THD + N Ratio (A Weighted).
- 32K - 192 KHz. Sampling Rates.
- Independent Digital Volume Control.
- I2S, Left and Right Justified Digital Input Formats.
- On -chip Reconstruction Filters.
• 2-wire Serial Control Interface.
• Single 3.3 Volt Power Supply.
The CE2766 support data conversion from 32K to
192KHz. The chip is operated at 3.3 volt to simplify the
power requirement. The CE2766 is ideal for DVD player,
AV receiver and set-top box application.
The CE2766 support 32, 24, 20 and 16-bit input data. It
also support multiple sampling frequency data. Each DAC
has its own individual volume control.
DIN1
80
DIN2
80
DIN3
77
LRCK
77
BCK
78
• Digital Surround Sound For Home Theatre
• DVD
• Car Audio.
CE2766
PLL
XCK
Applications
Σ∆
Mod.
DIGITAL
AUDIO
INPUT
Σ∆
Mod.
INTERPOLATION
FILTER
Σ∆
Mod.
Clock Rate
Detect'n
Control
SDA
CEI Microelectronics Co. Ltd.
1-19
D/A
AR1
D/A
AL1
D/A
AR2
D/A
AL2
D/A
AR3
D/A
AL3
Interface
SCL
15
15
RST
VCM
June 25, 2005
CE2766
DAC Performance
Item
PERFORMANCE SPECIFICATIONS
Spec.
1
Audio Output Level
1 Vrms
2
Audio Bandwidth 20Hz - 20 KHz
+/- 0.1 dB
3
SNR (A-weight)
>101 dB
4
THD + NOISE (A-weight, 0 dB input)
< -82 dB
5
Dynamic Range
90 dB
6
Channel Separation
< -90 dB
7
Nonlinear Distortion
< 0.25 dB
8
Channel Gain Error
< 0.1 dB
All Measurement were taken with only one channel active.
2-19
June 25, 2005
CE2766
XCK REQUIREMENT
The CE2766 supports 384 and 256 times sampling clock for 32, 44.1, 48, 96 and 192K audio; 192 or 128 times for the 96 K
audio.; and 96 and 64 times for the 192K audio.
XCK Requirement
Sampling
Rate
XCK Freq.
CREG1[5:4]=[0 0]
CREG1[5:4]=[0 1]
CREG1[5:4]=[1 0]
Normal XCK
2 times XCK
4 times XCK
fs
384*fs
256*fs
2*384*fs
2*256*fs
32 K
12.288 MHz
8.192 MHz
44.1
16.934 Mhz
11.29 Mhz.
48 K
18.432 MHz
12.288 Mhz.
96 K
18.432 MHz
12.288 Mhz.
36.864 MHz
24.576 Mhz.
192 K
18.432 Mhz
12.288 Mhz.
36.864 Mhz
24.576 Mhz.
4*384*fs
4*256*fs
73.728 Mhz
49.152 Mhz.
Normal XCK is prefered for all sampling rates.
3-19
June 25, 2005
CE2766
PIN ASSIGNMENT
DVDD
28
AVDD
XCK
2
27
AR1
BCK
3
26
GR1
LRCK
4
25
AL1
DIN1
5
24
AGND
DIN2
6
23
AR2
DIN3
7
22
GR2
TST
8
21
AL2
RSTZ
9
20
AGND
10
19
AR3
11
18
GR3
12
17
AL3
SDA
13
16
VCM
SCL
14
15
AVDD
N/C
DGND
TSTOUT
CE2766
1
PIN DESCRIPTION
Pin Name
Pin #
Type
Description
DVDD
1
+3.3V
XCK
2
I
External Master Clock Input.
BCK
3
I
Audio Serial Data Clock Input.
LRCk
4
I
Left/Right Channel Clock pin. Please refer to Figure 1, Input data format for its
definition
DIN1
5
I
Channel 1 or TDM Serial Audio Data Input.
DIN2
6
I
Channel 2 Serial Audio Data Input.
DIN3
7
I
Channel 3 Serial Audio Data Input.
TST
8
I
Test pin. This pin should be connected to ground.
RSTZ
9
I/O
N/C
10
DGND
11
DIGITAL
Digital power supply, 3.3 Volt.
Active Low Reset Pin.
Not used. can connected to ground.
GND
Digital ground
4-19
June 25, 2005
CE2766
PIN DESCRIPTION (Continued)
Pin Name
Pin #
Type
T
Description
TSTOUT
12
Tri-state output pin, This pin can be connected to ground or leave open
SDA
13
I/O
SCL
14
I
AVDD
28
+3.3V
AR1
27
O
GR0
26
GND
AL1
25
O
AGND
24
GND
AR2
23
O
GR1
22
GND
AL2
21
O
AGND
20
GND
AR3
19
O
GR2
18
GND
AL3
17
O
Analog right channel 3 output
VCM
16
I/O
Common voltage De-coupling Pin Should be Connected to a 20 uF capacitor in parallel
with a 1 uF.
AVDD
15
+3.3V
Analog circuits power supply.Should be Connected to a a 100 uF. in parallel with a 1
uF.
I2C data bus. Open drain output. Externally this pin should tie to a 680 ohm pull up
resistor.
I2C clock input.
Analog
Analog circuits power supply.Should be Connected to a 100 uF capacitor in parallel
with a 1 uF.
Analog right channel 1 output
Analog circuits ground
Analog left channel 1 output
Analog circuits ground
Analog right channel 2 output
Analog circuits ground
Analog left channel 2 output
Analog circuits ground
Analog right channel 3 output
Analog circuits ground
5-19
June 25, 2005
CE2766
DIGITAL AUDIO SERIAL INTERFACE
The digital serial interface consists of 3 serial input pins, DIN1, DIN2, DIN3, and one serial clock input pin, BCK, and one
left/right indicator input pin, LRCK. The data are 2’s complement MSB first numbers. The CE2766 supports four resolution,
which are selected programming the control register CREG0[5:4] via the I2C serial control port. Table 1 describes these four
resolution.
Table (1): Audio Serial Data Input Resolution,
Format
CREG0[5:4]
DIN[3:1]
0
00
16-bit (default)
1
01
20-bit
2
10
24-bit
3
11
32-bit
The DIN3, DIN2 and DIN1 can be either 24-bit or 32-bit per frame as well as left justified, right justified or I2S. The CE2766
counts the number of BCK per frame to determine whether the input is 24 or 32 bits format.
Table (2): Audio Serial Data Input Modes
Mode
CREG0[7:6]
DIN[3:1]
0
00
Right Justified
1
01
Left Justified
2
10
I2S (default)
3
11
TDM
TDM Input Format
The CE2766 support Time Division Multiplexed data input. In this format only one data input pin is required. The six channel
data are sent in serial order, channel 1 first, followed by channel 2 and so forth. The number of bits per channel is defined by
CREG0[5:4].
6-19
June 25, 2005
CE2766
Figure 1. Audio Serial Input Data Format
1/fs
left Channel
right channel
LRCK
BCK
MSB
LSB
n
DIN[1:3]
3
2
MSB
LSB
n
1
3
2
1
Right Justified Input Format
left Channel
right channel
LRCK
BCK
MSB
MSB
LSB
DIN[1:3]
3
2
LSB
1
3
2
1
Left Justified Input Format
left Channel
right channel
LRCK
BCK
MSB
LSB
DIN[1:3]
3
2
MSB
LSB
1
3
2
1
2
I S Input Format
LRCK
BCK
MSB
DIN[1]
n
LSB MSB
3
2
Channel 0
1
LSB
n
3
2
1
Channel 1
MSB
n
LSB
2
1
data = 0
Last Channel
TDM Input Format
7-19
June 25, 2005
CE2766
INFINITE ZERO DETECTION
The CE2766 has an Infinite Zero Detection circuit which detects zero in the Audio Serial Port that lasts for approximately 0.1
sec. By default, the zero detection circuit is on.
Serial Command Port
The user can select the chip operation mode by programming the internal control registers through serial I2C port. The Chip
Address for the CE2766 is 35H. The protocol for write operation consists of sending 3 byte data to CE2766, following each
byte is the acknowledges generated by CE2766. The first byte is the 7-bit Chip Address followed by the read/write bit (read is
high, write is low). The second byte is the control register address. The third byte is the control register data.
Upon power up, all programmable registers are set to default values. Figure 2 describes the serial command port timing
relationship.
Figure 2. Serial Command Port Timing
I 2 C Bus Control Register Write Example:
first byte
Start
second byte
CA0
CA6
R/W
ACK
A7
third byte
A0
ACK
D7
D0
SDA
1
1
1
1
SCL
Example
Set channel 1L volume to 30H:
first byte: [CA R/W] = 6AH
( Note: Chip adrress: CA<6:0> = 35H, R/W =0.)
second byte: register address: A<7:0> = 02H
third byte: data D<7:0> = 30H
8-19
June 25, 2005
ACK
Stop
CE2766
SERIAL PORT CONTROL REGISTER ASSIGNMENT
There are 8 registers dedicated to the CE2766 for chip functional programming, The register addresses assignments are
Address
(decimal)
Register
Default
Value
Register Function
0
CREG0[7:0]
80
Data input format, de-emphasis filter selection
1
CREG1[7:0]
80
Input format and PLL output frequency selection
2
VOLREG0[7:0]
80
Volume control for channel 1, left
3
VOLREG1[7:0]
80
Volume control for channel 1, right
4
VOLREG2[7:0]
80
Volume control for channel 2, left
5
VOLREG3[7:0]
80
Volume control for channel 2, right
6
VOLREG4[7:0]
80
Volume control for channel 3, left
7
VOLREG5[7:0]
80
Volume control for channel 3, right
9-19
June 25, 2005
CE2766
CONTROL REGISTERS DESCRIPTION
Control Register 0(ADRS=hex00, default=hex80)
CREG0[7:0]
ADDR[3:0]
Hex 00
Default Value
BIT 7
BIT 6
I2S
LF
1
0
BIT 5
BIT 4
NBIT[1:0]
0
0
BIT 3
BIT 2
AMUTE
DEEMP
0
0
BIT 1
BIT 0
FSMPL[1:0]
0
0
[I2S, LF] Digital Serial Bus Format Select
00: - Normal or Right Justified Format.
01: -Left Justified Format.
10: - I2S Format.(default)
11: - TDM, Multi-channel Time Division Multiplexed Format
NBIT[1:0]: - These two bits define the serial audio input resolution for right justified and TDM mode
00: - 16-bit resolution. (default)
01: - 20-bit resolution.
10: - 24-bit resolution.
11: - 32-bit resolution.
AMUTE: - Auto-mute detection enable.
0: - Auto-mute enabled. (default)
1: - No auto-mute.
DEEMP: - Enable de-emphasis
0: - Normal. (default)
1: - enable de-emphasis.
FSMPL: - Interpolation filter selection.
These two bits are recognized only when “AUTODET” bit of the CREG1 is set to ‘0’.
00: - 44.1 or 48K sampling.(default)
01: - 44.1 or 48K sampling.
10: - 96K sampling.
11: - 192K sampling.
10-19
June 25, 2005
CE2766
Control Register 1 (ADRS=hex01, default=hex80)
CREG1[7:0]
ADDR[3:0]
Hex 01
Default Value
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
AUTODET
FS384
CKDIV4
CKDIV2
CKdet
MUTE56
MUTE34
MUTE12
1
0
0
0
0
0
0
0
AUTODET Automatically detects the serial audio input data sampling rate clock frequency.
0: - do not use auto-detect
1: - automatically detects the serial audio input data sampling rate and clock frequency.
FS384: 384 fs or 256 fs control for the PLL clock output. This bit is recognized only when “AUTODET” bit is set to ‘0’
otherwise the input format is automatically detected.
0: the PLL takes the reference clock and multiplies it by 2 to generate a 512 bit clock
1: the PLL takes the reference clock and multiplies it by 4/3 to generate a 512 bit clock
CKDIV4: Clock divider enable control.This bit is recognized only when “AUTODET” bit is set to ‘0’ otherwise the input
format is automatically detected.
0: do not enable input clock divided by 4
1: enable input clock divided by 4
CKDIV2: Clock divider enable control . This bit is recognized only when “AUTODET” bit is set to ‘0’ otherwise the
input format is automatically detected.
0: do not enable input clock divided by 2
1: enable input clock divided by 2
CKdet: turn off clock detection.
0: enable clock detection. The chip will be in reset mode when there are no clock.
1: disable clock detection.
MUTE56: Mute control for channels 5 and 6
0: do not mute channels 5 and 6
1: simultaneously mute channels 5 and 6
MUTE34: Mute control for channels 3 and 4
0: do not mute channels 3 and 4
1: simultaneously mute channels 3 and 4
MUTE12: Mute control for channels 1 and 2
0: do not mute channels 1 and 2
1: simultaneously mute channels1 and2
11-19
June 25, 2005
CE2766
Volume Registers for channel 1 to channel 3, (ADRS=hex02 - hex07, default=hex80)
Volume Registers
ADDR[3:0]
BIT 7
BIT 6
BIT 5
BIT 4
Hex 02
Channel 1 left volume register, VOLREGL1[7:0]
Hex 03
Channel 1 right volume register, VOLREGR1[7:0]
Hex 04
Channel 2 left volume register, VOLREGL2[7:0]
Hex 05
Channel 2 right volume register, VOLREGR2[7:0]
Hex 06
Channel 3 left volume register, VOLREGL3[7:0]
Hex 07
Channel 3 right volume register, VOLREGR3[7:0]
Default Value
1
0
0
BIT 3
BIT 2
BIT 1
BIT 0
0
0
0
0
0
VOLREG:- Control the volume of the 6 DAC’s
Volume is controlled in linear scale, with 80h corresponding to 0 dB and 01h to -42 dB. The following table
showes the typical attenuation settings and their repective register values.
Attenuation and VOLREG setting example
Attenuation
(dB)
Reg.
value
Attenuation
(dB)
Reg.
value
Attenuation
(dB)
Reg.
value
Attenuation
(dB)
Reg.
value
0
128
-8
51
-16
20
-25
7
-1
114
-9
45
-17
18
-27
6
-2
102
-10
40
-18
16
--28
5
-3
91
-11
36
-20
13
-30
4
-4
81
-12
32
-21
11
-33
3
-5
72
-13
29
-22
10
-36
2
-6
64
-14
26
-23
9
-42
1
-7
57
-15
23
-24
8
-α
0
12-19
June 25, 2005
CE2766
APPLICATION CONNECTION EXAMPLE:
6.8 Ohm
180 Ohm
22 uF
Over Sample Clock
2
3
4
Digital Audio
Interface
5
6
7
1
15
DVDD
AVDD
AVDD
BCK
AR1
LRCK
AL1
DIN1
AR2
DIN3
AL2
+3.3 Volt
AR3
CE2766
680 ohm
13
I 2 C Serial
Interface
14
8
Reset
AL3
SDA
VCM
28
100 uF
27
25
23
21
19
17
16
SCL
22 uF
GR1 26
GR2 22
TST
9
GR3 18
RST
DGND
All Unmarked
Capacitors have
values of 0.1 uF
100 uF
XCK
DIN2
Analog
3.3 Volt
11
13-19
AGND
20
24
June 25, 2005
CE2766
SUGGESTED ANALOG RECONSTRUCTION FILTER
A second Sallen Key low pass reconstruction filter is recommend to remove the high frequency sigma delta modulator noise.
The filter’s component values and characteristic are shown in the following figures.
Sallen Key 2nd order LP filter
1000 pF
4.7 uF
2.7 K
10 K
+
100 K
680 pF
10 K
10 K
All resistors and capicitors are
5% precision.
LP F F requenc y Res pons e
5
0
Amplitude (dB)
-5
-10
-15
-20
-25
-30
10
3
10
4
10
5
F req (H z .)
14-19
June 25, 2005
CE2766
TIMING DIAGRAM
Figure 3. Audio Serial Interface Timing Requirement
tbck
tbck
tbck
H
L
BCK
tkd su
DIN[1-3]
tkd hd
tkr su
LRCK
tkr hd
Figure 4. Serial Command Port Write Timing Requirement
tSCL
tLOW
tHIGH
SDA, SCL
tF
tBF
tHD,sta
tR
tHD,dat
tSU,dat
tSU,sta
tSU,stp
SDA
SCL
stop
start
start
15-19
stop
June 25, 2005
CE2766
ABSOLUTE MAXIMUM RATINGS
Symbol
Characteristics
Min
Max
Units
VDD
Power Supply Voltage (Measured to GND)
Vi
Digital Input Applied Voltage2
GND-0.5
Ai
Digital Input Forced Current3,4
-100
100
mA
Vo
Digital Output Applied Voltage2
GND-0.5
VDD+0.5
V
Ao
Digital Output Forced Current3,4
-100
100
mA
TDsc
Digital Short Circuit Duration (single output high state to Vss)
1
Sec
TASC
Analog Short Circuit Duration (single output to VSS1)
infinite
Sec
Ta
Ambient Operating Temperature Range
-25
+125
o
C
Tj
Junction Temperature (Plastic Package)
-65
+150
o
C
Tsol
Lead Soldering Temperature (10 sec., 1/4” from pin)
280
o
C
Tvsol
Vapor Phase Soldering (1 minute)
220
o
C
Tstor
Storage Temperature
+150
o
C
-0.5
-65
+7.0
V
V
Notes:
1. Absolute maximum ratings are limiting values applied individually, while all other parameters are within specified
operating conditions.
2. Applied voltage must be current limited to specified range, and measured with respect to VSS.
3. Forcing voltage must be limited to specified range.
4. Current is specified as conventional current, flowing into the device.
16-19
June 25, 2005
CE2766
ELECTRICAL CHARACTERISTICS
Parameter
Characteristics
Min
Typ
Max
Units
Power Supply
AVDD
Analog power supply voltage
2.8
3.3
5.5
V
DVDD
Digital power supply voltage
2.8
3.3
5.5
V
IDA
Analog Current
40
IDD
Digital Current
16
18
mA
1
1.02
Vrms
mA
Audio DAC Characteristics
Full Scale Output Voltage to a 10K load
VVCM
.98
Reference voltage
VDD/2
V
Digital Characteristics
VIH
Digital Input Voltage, Logic HIGH,
TTL Compatible Inputs.
IOZH
2.0
VDD
V
Hi-Z Leakage Current, HIGH,
VDD=Max, VIN=3.3 Volt
33
µA
IOZL
Hi-Z Leakage Current, LOW,
VDD=Max, VIN=VSS)
-10
µA
CI
Digital Input Capacitance (TA=25oC, f=1Mhz)
8
pF
CO
Digital Output Capacitance (TA=25oC, f=1Mhz)
10
pF
Audio Serial Interface Timing
tbck
BCK Cycle Time
80
ns
tbckH
BCK Pulse Width, HIGH
30
ns
tbckL
BCK Pulse Width, LOW
30
ns
tkdsu
Audio Data Setup Time With Respect To Rising
Edge of BCK
10
ns
tkdhd
Audio Data Hold Time With Respect to Rising
Edge of BCK
15
ns
tkrsu
Audio LRCK Setup Time With Respect To Rising
Edge of BCK
10
ns
17-19
June 25, 2005
CE2766
Parameter
tkrhd
Characteristics
Min
Audio LRCK Hold Time With Respect To Rising
Edge of BCK
Typ
Max
15
Units
ns
Serial Command Port
fSCL
SCL Clock Frequency
tSU,sta
Start condition set up time
4.7
us
tHD,sta
Start condition hold time
4.0
us
tSU,stp
Stop condition set up time
4.0
us
tLOW
SCL Low time
4.7
us
tHIGH
SCL High time
4.0
us
tR
SCL & SDA rise time
1.0
us
tF
SCL & SDA fall time
0.3
us
tSU,DAT
Data set-up time
tHD,DAT
tBF
100
kHz
250
ns
Data hold time
0
ns
Bus Free time
4.7
us
18-19
June 25, 2005
CE2766
PACKAGING INFORMATION
Dimensions
mm.
min
norm
A
A1
0.05
b
0.22
C
0.09
D
9.90
0.3
10.20
mm.
max
min
norm
max
2.13
E1
5.0
5.3
5.6
0.25
E2
7.4
7.8
8.2
0.38
e
0.20
L
0.65
0.63
0.9
1.03
10.50
28-Pin (SSOP)
D
E1
E2
A1
A
b
e
c
L
19-19
June 25, 2005