SONY CXD2304

CXD2304R
8-bit 20 MSPS RGB 3-Channel D/A Converter
Description
The CXD2304R is an 8-bit high-speed D/A
converter for video band use. It has an input/output
equivalent to 3 channels of R, G and B. It is suitable
for use of digital TV, graphic display, and others.
Features
• Resolution 8-bit
• Maximum conversion speed 20 MSPS
• RGB 3-channel input/output
• Differential linearity error ±0.5 LSB
• Low power consumption 50 mW
(330 Ω load at 1.2 Vp-p output)
• Single 3.3 V power supply
• Low glitch noise
• Stand-by function
Structure
Silicon gate CMOS IC
48 pin LQFP (Plastic)
Absolute Maximum Ratings (Ta=25 °C)
• Supply voltage
AVDD, DVDD
7
V
• Input voltage (All pins)
VIN VDD+0.5 to VSS–0.5 V
• Output current (Every each channel)
IOUT
0 to 15
mA
• Storage temperature Tstg
–55 to +150
°C
Recommended Operating Conditions
• Supply voltage
AVDD, AVSS 3.0 to 3.6
V
DVDD, DVSS 3.0 to 3.6
V
• Reference input voltage
VREF
1.2
V
• Clock pulse width
TPW1, TPW0 22.5 ns (min.) to 1.1 µs (max.)
• Operating temperature
Topr
–40 to +85
°C
Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by
any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the
operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits.
—1—
E94307B01
CXD2304R
Block Diagram
(LSB) R0
1
R1
2
R2
3
R3
4
R4
5
R5
6
R6
7
(MSB) R7
8
(LSB) G0
9
2LSB’S
CURRENT
CELLS
DECODER
47 DVDD
48 DVDD
36 RO
6MSB’S
CURRENT
CELLS
LATCHES
37 RO
27 RCK
DECODER
CLOCK
GENERATOR
43 AVDD
44 AVDD
2LSB’S
CURRENT
CELLS
G1 10
45 AVDD
46 AVDD
G2 11
38 GO
G3 12
DECODER
6MSB’S
CURRENT
CELLS
LATCHES
G4 13
G5 14
G6 15
39 GO
28 GCK
DECODER
CLOCK
GENERATOR
(MSB) G7 16
2LSB’S
CURRENT
CELLS
(LSB) B0 17
B1 18
33 AVSS
30 DVSS
31 DVSS
B2 19
40 BO
B3 20
DECODER
6MSB’S
CURRENT
CELLS
LATCHES
B4 21
B5 22
B6 23
41 BO
29 BCK
DECODER
CLOCK
GENERATOR
(MSB) B7 24
42 VG
34 VREF
BLK 25
CE 26
CURRENT CELLS
(FOR FULL SCALE)
BIAS VOLTAGE
GENERATOR
—2—
35 IREF
32 VB
CXD2304R
RO
IREF
VREF
AVSS
VB
DVSS
DVSS
BCK
GCK
RCK
CE
BLK
Pin Configuration
36
35
34
33
32
31
30
29
28
27
26
25
19 B2
AVDD
43
18 B1
AVDD
44
17 B0
AVDD
45
16 G7
AVDD
46
15 G6
DVDD
47
14 G5
DVDD
48
13 G4
1
2
3
4
5
6
7
8
9
10
11
12
G3
VG
G2
20 B3
42
G1
41
G0
BO
R7
21 B4
R6
40
R5
BO
R4
22 B5
R3
23 B6
GO 39
R2
GO 38
R1
24 B7
R0
RO 37
Pin Description and I/O Pins Equivalent Circuit
Pin No.
Symbol
1 to 8
R0 to R7
I/O
Equivalent circuit
DVDD
Digital input
R0 (LSB) to R7 (MSB)
G0 (LSB) to G7 (MSB)
B0 (LSB) to B7 (MSB)
1
9 to 16
G0 to G7
I
to
24
17 to 24
DVSS
B0 to B7
DVDD
25
BLK
Description
I
Blanking input.
This is synchronized with the clock
input signal for each channel.
No signal at “H” (Output 0 V).
Output condition at “L”.
25
DVSS
DVDD
DVDD
32
VB
O
Connect a capacitor of about 0.1 µF.
32
DVSS
—3—
CXD2304R
Pin No.
Symbol
27
RCK
I/O
Equivalent circuit
Description
DVDD
27
28
GCK
I
Clock input.
28
29
29
BCK
30, 31
33
DVSS
AVSS
DVSS
—
—
Digital GND
Analog GND
DVDD
26
CE
I
Chip enable input.
This is not synchronized with the
clock input signal.
No signal (Output 0 V) at “H” and
minimizes power consumption.
26
DVSS
35
IREF
Reference current output.
Connect a resistance 16 times “RIR”
that of output resistance value
“ROUT”.
O
AVDD
AVDD
35
AVDD
AVSS
34
VREF
I
34
AVDD
AVSS
Reference voltage output.
Set full scale output value.
42
AVSS
42
VG
O
Connect a capacitor of about 0.1 µF.
43 to 46
AVDD
—
Analog VDD
—4—
CXD2304R
Pin No.
Symbol
37
RO
I/O
Equivalent circuit
Current output.
Voltage output can be obtained by
connecting a resistance.
AVDD
39
Description
GO
37
39
41
41
BO
AVSS
AVDD
O
36
RO
36
38
40
38
Inverted current output.
Normally dropped to analog GND.
GO
AVSS
40
BO
47, 48
DVDD
—
Digital VDD
—5—
CXD2304R
Electrical Characteristics
Item
(FCLK=20 MHz, AVDD=DVDD=3.3 V, ROUT=330 Ω, VREF=1.2 V, RIR=5.1 kΩ, Ta=25 °C)
Resolution
Symbol
n
Conversion speed
FCLK
Integral non-linearity error
Differential non-linearity error
Output full-scale voltage
Output full-scale ratio ∗1
Output full-scale current
Output offset voltage
Glitch energy
Crosstalk
EL
ED
VFS
FSR
IFS
VOS
GE
CT
IDD
ISTB
RIN
CI
VIH
VIL
IIH
IIL
ts
th
tPD
tE
tD
Supply current
Analog input resistance
Input capacitance
Digital input voltage
Digital input current
Setup time
Hold time
Propagation delay time
CE enable time ∗2
CE disable time ∗2
∗1
∗2
Measurement conditions
AVDD=DVDD=3.0 to 3.6 V
Ta=–40 to 85 °C
Endpoint
Min.
Typ.
8
Max.
Unit
bit
0.5
20
MSPS
–2.5
–0.5
1.12
0
2.5
0.5
1.36
3.0
LSB
LSB
V
%
mA
mV
pV•s
dB
1.24
1.5
3.8
1
When “00000000” data input
When 1 kHz sine wave input
When 14.3 MHz color CE= “L”
bar data input
CE= “H”
VREF
150
53
15
18
1.2
1
9
AVDD=DVDD=3.0 to 3.6 V
Ta=–20 to +75 °C
AVDD=DVDD=3.0 to 3.6 V
Ta=–20 to +75 °C
2.5
0.5
–5
CE=H→L
CE=L→H
Full-scale voltage of channel
–1
Average of the full-scale voltage of the channels
When the external capacitors for the VG pins are 0.1 µF.
Full-scale output ratio =
—6—
MΩ
pF
V
5
µA
8
8
ns
ns
ns
ms
ms
7
3
20
4
4
mA
× 100 (%)
CXD2304R
Electrical Characteristics Measurement Circuit
Analog Input Resistance
Measurement Circuit
Digital Input Current
}
+3.6V
AVDD, DVDD
A
CXD2304R
V
AVSS, DVSS
Maximum Conversion Velocity Measurement Circuit
R0 to R7
1 to 8
8bit
COUNTER
with
LATCH
G0 to G7
17 to 24
B0 to B7
17 to 24
RO 37
330
330
AVSS
BO 41
330
25 BLK
0.1µ
AVSS
GO 39
AVSS
26 CE
32 VB
AVDD
VG 42
DVSS
CLK
20MHz
SQUARE
WAVE
27 RCK
VREF 34
28 GCK
IREF 35
29 BCK
0.1µ
1k
5.1k
AVSS
—7—
OSCILLOSCOPE
CXD2304R
Setup Time
Hold Time
Glitch Energy
}
Measurement Circuit
R0 to R7
1 to 8
8bit
COUNTER
with
LATCH
RO 37
G0 to G7
9 to 16
330
AVSS
GO 39
B0 to B7
17 to 24
BO 41
330
AVSS
25 BLK
0.1µ
DELAY
CONTROLLER
26 CE
32 VB
AVDD
VG 42
DVSS
CLK
1MHz
SQUARE
WAVE
OSCILLOSCOPE
330
AVSS
DELAY
CONTROLLER
27 RCK
VREF 34
28 GCK
IREF 35
0.1µ
1k
5.1k
29 BCK
AVSS
Crosstalk Measurement Circuit
R0 to R7
1 to 8
DIGITAL
WAVEFORM
GENERATOR
RO 37
ALL “1”
330
G0 to G7
9 to 16
330
B0 to B7
17 to 24
AVSS
BO 41
330
25 BLK
0.1µ
AVSS
GO 39
AVSS
26 CE
32 VB
AVDD
VG 42
DVSS
CLK
20MHz
SQUARE
WAVE
27 RCK
VREF 34
28 GCK
IREF 35
0.1µ
1k
5.1k
29 BCK
AVSS
—8—
SPECTRUM
ANALYZER
CXD2304R
DC Characteristics Measurement Circuit
R0 to R7
1 to 8
RO 37
330
G0 to G7
9 to 16
CONTROLLER
AVSS
GO 39
AVSS
BO 41
330
25 BLK
0.1µ
DVM
330
B0 to B7
17 to 24
AVSS
26 CE
32 VB
AVDD
VG 42
DVSS
CLK
20MHz
SQUARE
WAVE
27 RCK
VREF 34
28 GCK
IREF 35
0.1µ
1k
5.1k
29 BCK
AVSS
Propagation Delay Time Measurement Circuit
R0 to R7
1 to 8
FREQUENCY
DEMULTIPLIER
RO 37
330
G0 to G7
9 to 16
AVSS
GO 39
B0 to B7
17 to 24
AVSS
BO 41
330
25 BLK
0.1µ
OSCILLOSCOPE
330
AVSS
26 CE
32 VB
AVDD
VG 42
DVSS
CLK
1MHz
SQUARE
WAVE
27 RCK
VREF 34
28 GCK
IREF 35
0.1µ
1k
5.1k
29 BCK
AVSS
SNR Measurement Circuit
ALL “1”
R0 to R7
1 to 8
DIGITAL
WAVEFORM
GENERATOR
RO 37
330
G0 to G7
9 to 16
SPECTRUM
ANALYZER
330
B0 to B7
17 to 24
AVSS
BO 41
330
25 BLK
0.1µ
AVSS
GO 39
ALL “1”
AVSS
26 CE
32 VB
AVDD
VG 42
DVSS
CLK
20MHz
SQUARE
WAVE
27 RCK
VREF 34
28 GCK
IREF 35
0.1µ
1k
5.1k
29 BCK
AVSS
SNR : Different between primary
—9—
component and secondary distortion
CXD2304R
Description of Operation
Timing Chart
tPW1
tPW0
1.5V
CLK
AA
AA
AA
AAA
AA
AA
AA
AAA
AA AAAAAAA
ts th
ts th
ts
th
DATA
tPD
D/A OUT
100%
50%
tPD
tPD
0%
I/O Chart (when full scale output voltage at 1.2 V)
Input code
MSB
LSB
1 1 1 1 1 1 1 1
:
1 0 0 0 0 0 0 0
:
0 0 0 0 0 0 0 0
Output voltage
1.2 V
0.6 V
0V
B (Blue) OUT
Application Circuit
330
AVSS
G (Green) OUT
330
AVDD
DVDD
AVSS
R (Red) OUT
0.1µ
330
48 47 46 45 44 43 42 41 40 39 38 37
AVSS
(LSB)
•
•
•
R (Red) IN
•
•
(MSB)
(LSB)
•
•
1
36
2
35
3
34
4
5
33
6
31
7
30
8
(BCK) 29
9
(GCK) 28
10
(RCK) 27
11
26
12
25
•
•
•
•
•
•
5.1k
AVSS
AVSS
0.1µF
DVSS
CLOCK IN
DVSS
(MSB)
(LSB)
•
(MSB)
•
AVDD
1k
32
13 14 15 16 17 18 19 20 21 22 23 24
G (Green) IN
1.2V
B (Blue) IN
Application circuits shown are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for
any problems arising out of the use of these circuits or for any infringement of third party patent and other right due to same.
—10—
CXD2304R
Notes on Operation
• How to select the output resistance
The CXD2304R is a D/A converter of the current output type. To obtain the output voltage connect the
resistance to the current output pins R0, G0 and B0. For specifications we have;
Output full scale voltage
VFS=1.12 to 1.36 [V]
Output full scale current
IFS=3.8 [mA] (typ.)
Calculate the output resistance value from the relation of VFS=IFS × ROUT. Also, 16 times resistance of the
output resistance ROUT is connected to reference current pin IREF. In some cases, however, this turns out to
be a value that does not actually exist. In such a case a value close to it can be used as a substitute.
Here please note that VFS becomes
VFS=VREF × 16ROUT/RIR.
VREF is the voltage set at the reference voltage pin VREF and ROUT is the resistance connected to the current
output pins RO, GO and BO while RIR is connected to IREF pin.
Increasing the resistance value can curb power consumption. On the other hand glitch energy and data
settling time will inversely increase. Set the most suitable value according to the desired application.
• Phase relation between data and clock
To obtain the expected performance as a D/A converter, it is necessary to set properly the phase relation
between data and clock applied from the exterior. Be sure to satisfy the provisions of the setup time (tS) and
hold time (tH) as stipulated in the Electrical Characteristics.
• Power supply and ground
To reduce noise effects separate analog and digital systems in the device periphery. For power supply pins,
both digital and analog, bypass respective grounds by using a ceramic capacitor of about 0.1 µF, as close as
possible to the pin.
• Latch up
Digital power supply and analog power supply have to be common at the PCB power supply source. This is
to prevent latch up due to voltage difference between AVDD and DVDD pins when power supply is turned ON.
• RO, GO and BO pins
The RO, GO and BO pins are the inverted current output pins described in the Pin Description. The sums
shown below become the constant value for any input data.
a) The sum of the currents output form RO and RO
b) The sum of the currents output form GO and GO
c) The sum of the currents output form BO and BO
However, the performances such as the linearity error of the inverted current output pin output current is not
guaranteed.
• Output full-scale voltage
For the applications using the RGB signal, the color balance may be broken up when the no-adjusted output
full-scale voltage is used.
—11—
CXD2304R
Latch Up Prevention
The CXD2304R is a CMOS IC which required latch up precautions. Latch up is mainly generated by the lag in
the voltage rising time of AVDD (Pins 43 to 46) and DVDD (Pins 47 and 48), when power supply is ON.
1. Correct usage
a. When analog and digital supplies are from different sources
DVDD
AVDD
43
44
45
46
47
AVDD
+5V
48
DVDD
+5V
CXD2304R
C
C
AVSS
DIGITAL IC
DVSS
33
30
31
AVSS
DVSS
b. When analog and digital supplies are from a common source
(i)
DVDD
43
44
45
46
47
AVDD
48
DVDD
+5V
CXD2304R
C
AVSS
C
DIGITAL IC
C
DIGITAL IC
DVSS
33
30
31
47
48
AVSS
DVSS
(ii)
DVDD
43
44
45
46
AVDD
DVDD
+5V
C
CXD2304R
AVSS
DVSS
33
30
31
AVSS
DVSS
—12—
CXD2304R
2. Example when latch up easily occurs
a. When analog and digital supplies are from different sources
DVDD
AVDD
43
44
45
46
47
AVDD
+5V
48
DVDD
+5V
CXD2304R
C
C
AVSS
DIGITAL IC
DVSS
33
30
31
AVSS
DVSS
b. When analog and digital supplies are from common source
(i)
DVDD
AVDD
43
44
45
46
47
AVDD
48
DVDD
+5V
CXD2304R
C
AVSS
C
DIGITAL IC
C
DIGITAL IC
DVSS
33
30
31
47
48
AVSS
DVSS
(ii)
DVDD
AVDD
43
44
45
46
AVDD
DVDD
+5V
CXD2304R
AVSS
DVSS
33
30
31
AVSS
DVSS
—13—
CXD2304R
SNR (Difference between primary and secondary) (dB)
Example of Representative Characteristics
Crosstalk CT (dB)
80
60
40
20
0.1M
1M
Output frequency FO (Hz)
Fig. 1. Crosstalk
10M
Power supply current IDD (mA)
Output fullscale voltage VFS (V)
0
1.27
1.26
0
Glitch energy GE (pV•s)
60
40
20
0
25
75
0
50
Ambient temperature Ta (°C)
Fig. 3. Ambient temperature vs.
Output full scale voltage
0.1M
1M
10M
Output frequency FO (Hz)
Fig. 2. SNR (Difference between primary
component and secondary distortion)
20
10
0
–25
10k
1M
100k
10M
Output frequency FO (Hz)
Fig. 4. Output frequency vs.
Power supply current
Reference measurement condition and
description
• AVDD=3.3 V
• DVDD=3.3 V
• VREF=1.2 V
• RIR=5.1 kΩ (≈16 ROUT in Fig. 5 only)
• Ta=25 °C (Except Fig. 3)
• Fig. 1, 2 Refer to the measurement circuit.
• Fig. 3 is input data=all 1
• Fig. 4 is input data=output of incremental
counter.
400
200
0
80
600
200
400
Output resistance ROUT (Ω)
Fig. 5. Output resistance vs. Glitch energy
—14—
CXD2304R
Unit : mm
48PIN LQFP (PLASTIC)
9.0 ± 0.2
∗
7.0 ± 0.1
36
S
25
13
0.5 ± 0.2
B
A
48
(8.0)
24
37
(0.22)
12
1
+ 0.05
0.127 – 0.02
0.5
+ 0.08
0.18 – 0.03
+ 0.2
1.5 – 0.1
0.13 M
0.1
S
(0.18)
0° to 10°
DETAIL B:SOLDER
DETAIL A
0.18 ± 0.03
0.127 ± 0.04
+ 0.08
0.18 – 0.03
(0.127)
+0.05
0.127 – 0.02
0.1 ± 0.1
0.5 ± 0.2
Package Outline
DETAIL B:PALLADIUM
NOTE: Dimension “∗” does not include mold protrusion.
PACKAGE STRUCTURE
PACKAGE MATERIAL
EPOXY RESIN
SONY CODE
LQFP-48P-L01
LEAD TREATMENT
SOLDER/PALLADIUM
PLATING
EIAJ CODE
LQFP048-P-0707
LEAD MATERIAL
42/COPPER ALLOY
PACKAGE MASS
0.2g
JEDEC CODE
—15—