AD AD5312 2.5 v to 5.5 v, 500 ua, parallel interface quad voltage-output 8-/10-/12-bit dac Datasheet

a
2.5 V to 5.5 V, 500 ␮A, Parallel Interface
Quad Voltage-Output 8-/10-/12-Bit DACs
AD5334/AD5335/AD5336/AD5344*
FEATURES
AD5334: Quad 8-Bit DAC in 24-Lead TSSOP
AD5335: Quad 10-Bit DAC in 24-Lead TSSOP
AD5336: Quad 10-Bit DAC in 28-Lead TSSOP
AD5344: Quad 12-Bit DAC in 28-Lead TSSOP
Low Power Operation: 500 ␮A @ 3 V, 600 ␮A @ 5 V
Power-Down to 80 nA @ 3 V, 200 nA @ 5 V via PD Pin
2.5 V to 5.5 V Power Supply
Double-Buffered Input Logic
Guaranteed Monotonic by Design Over All Codes
Output Range: 0–VREF or 0–2 V REF
Power-On Reset to Zero Volts
Simultaneous Update of DAC Outputs via LDAC Pin
Asynchronous CLR Facility
Low Power Parallel Data Interface
On-Chip Rail-to-Rail Output Buffer Amplifiers
Temperature Range: –40ⴗC to +105ⴗC
APPLICATIONS
Portable Battery-Powered Instruments
Digital Gain and Offset Adjustment
Programmable Voltage and Current Sources
Programmable Attenuators
Industrial Process Control
GENERAL DESCRIPTION
The AD5334/AD5335/AD5336/AD5344 are quad 8-, 10-, and
12-bit DACs. They operate from a 2.5 V to 5.5 V supply consuming just 500 µA at 3 V, and feature a power-down mode that
further reduces the current to 80 nA. These devices incorporate
an on-chip output buffer that can drive the output to both supply rails.
The AD5334/AD5335/AD5336/AD5344 have a parallel interface.
CS selects the device and data is loaded into the input registers
on the rising edge of WR.
The GAIN pin on the AD5334 and AD5336 allows the output
range to be set at 0 V to VREF or 0 V to 2 × VREF.
Input data to the DACs is double-buffered, allowing simultaneous
update of multiple DACs in a system using the LDAC pin.
On the AD5334, AD5335 and AD5336 an asynchronous CLR
input is also provided. This resets the contents of the Input
Register and the DAC Register to all zeros. These devices also
incorporate a power-on-reset circuit that ensures that the DAC
output powers on to 0 V and remains there until valid data is
written to the device.
The AD5334/AD5335/AD5336/AD5344 are available in Thin
Shrink Small Outline Packages (TSSOP).
AD5334 FUNCTIONAL BLOCK DIAGRAM
(Other Diagrams Inside)
VREFA/B
VDD
POWER-ON
RESET
AD5334
GAIN
DB
.. 7
.
INPUT
REGISTER
DAC
REGISTER
8-BIT
DAC
BUFFER
VOUTA
INPUT
REGISTER
DAC
REGISTER
8-BIT
DAC
BUFFER
VOUTB
INPUT
REGISTER
DAC
REGISTER
8-BIT
8-BIT
DAC
DAC
BUFFER
VOUTC
INPUT
REGISTER
DAC
REGISTER
8-BIT
DAC
BUFFER
VOUTD
DB0
CS
WR
A0
A1
INTERFACE
LOGIC
TO ALL DACS
AND BUFFERS
CLR
LDAC
*Protected by U.S. Patent Number 5,969,657; other patents pending.
POWER-DOWN
LOGIC
VREFC/D
PD
GND
REV. 0
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 2000
AD5334/AD5335/AD5336/AD5344–SPECIFICATIONS
(V = 2.5 V to 5.5 V, V = 2 V. R = 2 k⍀ to GND; C =200 pF to GND; all specifications T to T unless otherwise noted.)
DD
REF
L
L
MIN
MAX
2
Parameter1
Min
B Version
Typ
Max
Unit
Conditions/Comments
3, 4
DC PERFORMANCE
AD5334
Resolution
Relative Accuracy
Differential Nonlinearity
AD5335/AD5336
Resolution
Relative Accuracy
Differential Nonlinearity
AD5344
Resolution
Relative Accuracy
Differential Nonlinearity
Offset Error
Gain Error
Lower Deadband5
Upper Deadband
Offset Error Drift6
Gain Error Drift6
DC Power Supply Rejection Ratio6
DC Crosstalk6
DAC REFERENCE INPUT6
VREF Input Range
VREF Input Impedance
Bits
LSB
LSB
Guaranteed Monotonic By Design Over All Codes
10
± 0.5
± 0.05
±4
± 0.5
Bits
LSB
LSB
Guaranteed Monotonic By Design Over All Codes
0.25
OUTPUT CHARACTERISTICS6
Minimum Output Voltage4, 7
Maximum Output Voltage4, 7
DC Output Impedance
Short Circuit Current
Power-Up Time
LOGIC INPUTS6
Input Current
VIL, Input Low Voltage
± 16
±1
±3
±1
60
60
VDD
Bits
LSB
LSB
% of FSR
% of FSR
mV
mV
ppm of FSR/°C
ppm of FSR/°C
dB
µV
180
90
90
45
–90
–90
V
kΩ
kΩ
kΩ
kΩ
dB
dB
0.001
VDD – 0.001
0.5
50
20
2.5
5
V min
V max
Ω
mA
mA
µs
µs
±1
µA
V
V
V
V
V
V
pF
0.8
0.6
0.5
2.4
2.1
2.0
Pin Capacitance
POWER REQUIREMENTS
VDD
IDD (Normal Mode)
VDD = 4.5 V to 5.5 V
VDD = 2.5 V to 3.6 V
IDD (Power-Down Mode)
VDD = 4.5 V to 5.5 V
VDD = 2.5 V to 3.6 V
±1
± 0.25
12
±2
± 0.2
± 0.4
± 0.1
10
10
–12
–5
–60
200
Reference Feedthrough
Channel-to-Channel Isolation
VIH, Input High Voltage
8
± 0.15
± 0.02
3.5
2.5
5.5
V
600
500
900
700
µA
µA
0.2
0.08
1
1
µA
µA
Guaranteed Monotonic By Design Over All Codes
Lower Deadband Exists Only if Offset Error Is Negative
VDD = 5 V. Upper Deadband Exists Only if VREF = VDD
∆VDD = ± 10%
RL = 2 kΩ to GND, 2 kΩ to VDD; CL = 200 pF to GND;
Gain = 0
Gain = 1. Input Impedance = RDAC (AD5336/AD5344)
Gain = 2. Input Impedance = RDAC (AD5336)
Gain = 1. Input Impedance = RDAC (AD5334/AD5335)
Gain = 2. Input Impedance = RDAC (AD5334)
Frequency = 10 kHz
Frequency = 10 kHz
Rail-to-Rail Operation
VDD = 5 V
VDD = 3 V
Coming Out of Power-Down Mode. VDD = 5 V
Coming Out of Power-Down Mode. VDD = 3 V
VDD = 5 V ± 10%
VDD = 3 V ± 10%
VDD = 2.5 V
VDD = 5 V ± 10%
VDD = 3 V ± 10%
VDD = 2.5 V
All DACs active and excluding load currents.
VIH = VDD, VIL = GND.
IDD increases by 50 µA at VREF > VDD – 100 mV.
NOTES
1
See Terminology section.
2
Temperature range: B Version: –40°C to +105°C; typical specifications are at 25°C.
3
Linearity is tested using a reduced code range: AD5334 (Code 8 to 255); AD5335/AD5336 (Code 28 to 1023); AD5344 (Code 115 to 4095).
4
DC specifications tested with outputs unloaded.
5
This corresponds to x codes. x = Deadband voltage/LSB size.
6
Guaranteed by design and characterization, not production tested.
7
In order for the amplifier output to reach its minimum voltage, Offset Error must be negative. In order for the amplifier output to reach its maximum voltage, V REF = VDD and
“Offset plus Gain” Error must be positive.
Specifications subject to change without notice.
–2–
REV. 0
AD5334/AD5335/AD5336/AD5344
(VDD = 2.5 V to 5.5 V. RL = 2 k⍀ to GND; CL = 200 pF to GND. All specifications TMIN to TMAX unless other-
AC CHARACTERISTICS1 wise noted.)
2
Parameter
B Version3
Min
Typ
Max
Unit
6
7
7
8
0.7
8
0.5
3
0.5
3.5
200
–70
µs
µs
µs
µs
V/µs
nV-s
nV-s
nV-s
nV-s
nV-s
kHz
dB
Output Voltage Settling Time
AD5334
AD5335
AD5336
AD5344
Slew Rate
Major Code Transition Glitch Energy
Digital Feedthrough
Digital Crosstalk
Analog Crosstalk
DAC-to-DAC Crosstalk
Multiplying Bandwidth
Total Harmonic Distortion
8
9
9
10
Conditions/Comments
VREF = 2 V. See Figure 20
1/4 Scale to 3/4 Scale Change (40 H to C0 H)
1/4 Scale to 3/4 Scale Change (100 H to 300 H)
1/4 Scale to 3/4 Scale Change (100 H to 300 H)
1/4 Scale to 3/4 Scale Change (400 H to C00 H)
1 LSB Change Around Major Carry
VREF = 2 V ± 0.1 V p-p. Unbuffered Mode
VREF = 2.5 V ± 0.1 V p-p. Frequency = 10 kHz
NOTES
1
Guaranteed by design and characterization, not production tested.
2
See Terminology section.
3
Temperature range: B Version: –40°C to +105°C; typical specifications are at 25°C.
Specifications subject to change without notice.
TIMING CHARACTERISTICS1, 2, 3 (V
DD
= 2.5 V to 5.5 V, All specifications TMIN to TMAX unless otherwise noted.)
Parameter
Limit at TMIN, TMAX
Unit
Condition/Comments
t1
t2
t3
t4
t5
t6
t7
t8
t9
t10
t11
t12
t13
t14
t15
0
0
20
5
4.5
5
5
4.5
5
4.5
20
20
50
20
0
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns min
CS to WR Setup Time
CS to WR Hold Time
WR Pulsewidth
Data, GAIN, HBEN Setup Time
Data, GAIN, HBEN Hold Time
Synchronous Mode. WR Falling to LDAC Falling.
Synchronous Mode. LDAC Falling to WR Rising.
Synchronous Mode. WR Rising to LDAC Rising.
Asynchronous Mode. LDAC Rising to WR Rising.
Asynchronous Mode. WR Rising to LDAC Falling.
LDAC Pulsewidth
CLR Pulsewidth
Time Between WR Cycles
A0, A1 Setup Time
A0, A1 Hold Time
NOTES
1
Guaranteed by design and characterization, not production tested.
2
All input signals are specified with tr = tf = 5 ns (10% to 90% of V DD)
and timed from a voltage level of (V IL + VIH)/2.
3
See Figure 1.
t2
t1
CS
t 13
t3
Specifications subject to change without notice.
WR
t4
DATA,
GAIN,
HBEN
t6
LDAC
1
t7
t5
t8
t9
t 10
t 11
LDAC 2
t 14
CLR
t 15
t 12
A0,
A1
NOTES:
1 SYNCHRONOUS LDAC UPDATE MODE
2 ASYNCHRONOUS LDAC UPDATE MODE
Figure 1. Parallel Interface Timing Diagram
REV. 0
–3–
AD5334/AD5335/AD5336/AD5344
Reflow Soldering
Peak Temperature . . . . . . . . . . . . . . . . . . . . . . 220 +5/–0°C
Time at Peak Temperature . . . . . . . . . . . . .10 sec to 40 sec
ABSOLUTE MAXIMUM RATINGS*
(TA = 25°C unless otherwise noted)
VDD to GND . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +7 V
Digital Input Voltage to GND . . . . . . . . –0.3 V to VDD + 0.3 V
Digital Output Voltage to GND . . . . . . –0.3 V to VDD + 0.3 V
Reference Input Voltage to GND . . . . –0.3 V to VDD + 0.3 V
VOUT to GND . . . . . . . . . . . . . . . . . . . –0.3 V to VDD + 0.3 V
Operating Temperature Range
Industrial (B Version) . . . . . . . . . . . . . . . –40°C to +105°C
Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C
TSSOP Package
Power Dissipation . . . . . . . . . . . . . . . (TJ max – TA)/θJA mW
θJA Thermal Impedance (24-Lead TSSOP) . . . . . 128°C/W
θJA Thermal Impedance (28-Lead TSSOP) . . . . . 97.9°C/W
θJC Thermal Impedance (24-Lead TSSOP) . . . . . . 42°C/W
θJC Thermal Impedance (28-Lead TSSOP) . . . . . . 14°C/W
*Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the
device at these or any other conditions above those listed in the operational
sections of this specification is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability.
ORDERING GUIDE
Model
Temperature Range
Package Description
Package Option
AD5334BRU
AD5335BRU
AD5336BRU
AD5344BRU
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
–40°C to +105°C
TSSOP (Thin Shrink Small Outline Package)
TSSOP (Thin Shrink Small Outline Package)
TSSOP (Thin Shrink Small Outline Package)
TSSOP (Thin Shrink Small Outline Package)
RU-24
RU-24
RU-28
RU-28
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection. Although
the AD5334/AD5335/AD5336/AD5344 features proprietary ESD protection circuitry, permanent
damage may occur on devices subjected to high-energy electrostatic discharges. Therefore, proper
ESD precautions are recommended to avoid performance degradation or loss of functionality.
–4–
WARNING!
ESD SENSITIVE DEVICE
REV. 0
AD5334/AD5335/AD5336/AD5344
AD5334 PIN CONFIGURATION
AD5334 FUNCTIONAL BLOCK DIAGRAM
VREFA/B
VDD
POWER-ON
RESET
AD5334
GAIN
INPUT
REGISTER
DB
.. 7
.
DB0
A0
8-BIT
DAC
BUFFER
VOUTA
24
CLR
VREFA/B 2
23
GAIN
VOUTA 3
22
DB7
VOUTB 4
21
DB6
20
DB5
VOUTC 5
8-BIT
AD5334
VOUTD 6
TOP VIEW 19 DB4
GND 7 (Not to Scale) 18 DB3
CS
WR
DAC
REGISTER
VREFC/D 1
INPUT
REGISTER
DAC
REGISTER
8-BIT
DAC
BUFFER
VOUTB
INTERFACE
LOGIC
A1
INPUT
REGISTER
DAC
REGISTER
8-BIT
8-BIT
DAC
DAC
BUFFER
VOUTC
INPUT
REGISTER
DAC
REGISTER
8-BIT
DAC
BUFFER
VOUTD
CS 8
17
DB2
WR 9
16
DB1
A0 10
15
DB0
A1 11
14
VDD
LDAC 12
13
PD
TO ALL DACS
AND BUFFERS
CLR
LDAC
POWER-DOWN
LOGIC
VREFC/D
PD
GND
AD5334 PIN FUNCTION DESCRIPTIONS
Pin
No.
Mnemonic
Function
1
2
3
4
5
6
7
8
9
10
11
12
VREFC/D
VREFA/B
VOUTA
VOUTB
VOUTC
VOUTD
GND
CS
WR
A0
A1
LDAC
13
14
PD
VDD
15–22
23
24
DB0–DB7
GAIN
CLR
Unbuffered Reference Input for DACs C and D.
Unbuffered Reference Input for DACs A and B.
Output of DAC A. Buffered Output with Rail-to-Rail Operation.
Output of DAC B. Buffered Output with Rail-to-Rail Operation.
Output of DAC C. Buffered Output with Rail-to-Rail Operation.
Output of DAC D. Buffered Output with Rail-to-Rail Operation.
Ground Reference Point for All Circuitry on the Part.
Active Low Chip Select Input. This is used in conjunction with WR to write data to the parallel interface.
Active Low Write Input. This is used in conjunction with CS to write data to the parallel interface.
LSB Address Pin for Selecting which DAC Is to Be Written to.
MSB Address Pin for Selecting which DAC Is to Be Written to.
Active Low Control Input that Updates the DAC Registers with the Contents of the Input Registers.
This allows all DAC outputs to be simultaneously updated.
Power-Down Pin. This active low control pin puts all DACs into power-down mode.
Power Supply Pin. This part can operate from 2.5 V to 5.5 V and the supply should be decoupled with a
10 µF capacitor in parallel with a 0.1 µF capacitor to GND.
Eight Parallel Data Inputs. DB7 is the MSB of these eight bits.
Gain Control Pin. This controls whether the output range from the DAC is 0–VREF or 0–2 VREF
Asynchronous Active Low Control Input that Clears All Input Registers and DAC Registers to Zeros.
REV. 0
–5–
AD5334/AD5335/AD5336/AD5344
AD5335 FUNCTIONAL BLOCK DIAGRAM
AD5335 PIN CONFIGURATION
VREFA/B
VDD
POWER-ON
RESET
AD5335
HIGH BYTE
REGISTER
24
CLR
23
HBEN
VOUTA 3
22
DB7
VOUTB 4
21
DB6
20
DB5
VOUTC 5
DB
.. 7
..
.
.
DB0
LOW BYTE
REGISTER
CS
DAC
REGISTER
10-BIT
DAC
A0
LOW BYTE
REGISTER
INTERFACE
LOGIC
10-BIT
AD5335
VOUTD 6
BUFFER
VOUTA
HIGH BYTE
REGISTER
WR
A1
VREFC/D 1
VREFA/B 2
DAC
REGISTER
10-BIT
DAC
BUFFER
VOUTB
DAC
REGISTER
10-BIT
DAC
BUFFER
VOUTC
DAC
REGISTER
10-BIT
DAC
BUFFER
VOUTD
TOP VIEW 19 DB4
GND 7 (Not to Scale) 18 DB3
CS 8
17
DB2
WR 9
16
DB1
A0 10
15
DB0
A1 11
14
VDD
LDAC 12
13
PD
HIGH BYTE
REGISTER
HBEN
LOW BYTE
REGISTER
HIGH BYTE
REGISTER
LOW BYTE
REGISTER
TO ALL DACS
AND BUFFERS
RESET
CLR
POWER-DOWN
LOGIC
LDAC
VREFC/D
PD
GND
AD5335 PIN FUNCTION DESCRIPTIONS
Pin
No.
Mnemonic
Function
1
2
3
4
5
6
7
8
9
10
11
12
VREFC/D
VREFA/B
VOUTA
VOUTB
VOUTC
VOUTD
GND
CS
WR
A0
A1
LDAC
13
14
PD
VDD
15–22
23
DB0–DB7
HBEN
24
CLR
Unbuffered Reference Input for DACs C and D.
Unbuffered Reference Input for DACs A and B.
Output of DAC A. Buffered output with rail-to-rail operation.
Output of DAC B. Buffered output with rail-to-rail operation.
Output of DAC C. Buffered output with rail-to-rail operation.
Output of DAC D. Buffered output with rail-to-rail operation.
Ground Reference Point for All Circuitry on the Part.
Active Low Chip Select Input. This is used in conjunction with WR to write data to the parallel interface.
Active Low Write Input. This is used in conjunction with CS to write data to the parallel interface.
LSB Address Pin for Selecting which DAC Is to Be Written to.
MSB Address Pin for Selecting which DAC Is to Be Written to.
Active Low Control Input that Updates the DAC Registers with the Contents of the Input Registers.
This allows all DAC outputs to be simultaneously updated.
Power-Down Pin. This active low control pin puts all DACs into power-down mode.
Power Supply Pin. This part can operate from 2.5 V to 5.5 V and the supply should be decoupled with a
10 µF capacitor in parallel with a 0.1 µF capacitor to GND.
Eight Parallel Data Inputs. DB7 is the MSB of these eight bits.
This pin is used when writing to the device to determine if data is written to the high byte register or the
low byte register.
Asynchronous Active Low Control Input that Clears All Input Registers and DAC Registers to Zeros.
–6–
REV. 0
AD5334/AD5335/AD5336/AD5344
AD5336 PIN CONFIGURATION
AD5336 FUNCTIONAL BLOCK DIAGRAM
VREFA
VREFB
VDD
POWER-ON
RESET
AD5336
GAIN
INPUT
REGISTER
DB
.. 9
.
DB0
A0
10-BIT
DAC
BUFFER
VOUTA
28
CLR
27
GAIN
VREFB 3
26
DB9
VREFA 4
25
DB8
VOUTA 5
24
DB7
23
DB6
VOUTB 6
CS
WR
DAC
REGISTER
VREFD 1
VREFC 2
INPUT
REGISTER
DAC
REGISTER
10-BIT
DAC
BUFFER
VOUTB
INTERFACE
LOGIC
INPUT
REGISTER
A1
INPUT
REGISTER
DAC
REGISTER
DAC
REGISTER
10-BIT
DAC
10-BIT
DAC
BUFFER
VOUTC
BUFFER
10-BIT
AD5336
VOUTC 7
22
GND 9
20
DB3
CS 10
19
DB2
WR 11
18
DB1
A0 12
17
DB0
A1 13
16
VDD
LDAC 14
15
PD
DB5
TOP VIEW
VOUTD 8 (Not to Scale) 21 DB4
VOUTD
TO ALL DACS
AND BUFFERS
CLR
RESET
LDAC
POWER-DOWN
LOGIC
VREFD
PD
VREFC
GND
AD5336 PIN FUNCTION DESCRIPTIONS
Pin
No.
Mnemonic
Function
1
2
3
4
5
6
7
8
9
10
11
12
13
14
VREFD
VREFC
VREFB
VREFA
VOUTA
VOUTB
VOUTC
VOUTD
GND
CS
WR
A0
A1
LDAC
15
16
PD
VDD
17–26
27
28
DB0–DB9
GAIN
CLR
Unbuffered Reference Input for DAC D.
Unbuffered Reference Input for DAC C.
Unbuffered Reference Input for DAC B.
Unbuffered Reference Input for DAC A.
Output of DAC A. Buffered output with rail-to-rail operation.
Output of DAC B. Buffered output with rail-to-rail operation.
Output of DAC C. Buffered output with rail-to-rail operation.
Output of DAC D. Buffered output with rail-to-rail operation.
Ground Reference Point for All Circuitry on the Part.
Active Low Chip Select Input. This is used in conjunction with WR to write data to the parallel interface.
Active Low Write Input. This is used in conjunction with CS to write data to the parallel interface.
LSB Address Pin for Selecting which DAC Is to Be Written to.
MSB Address Pin for Selecting which DAC is to Be Written to.
Active Low Control Input that Updates the DAC Registers with the Contents of the Input Registers.
This allows all DAC outputs to be simultaneously updated.
Power-Down Pin. This active low control pin puts all DACs into power-down mode.
Power Supply Pin. This part can operate from 2.5 V to 5.5 V and the supply should be decoupled with a
10 µF capacitor in parallel with a 0.1 µF capacitor to GND.
10 Parallel Data Inputs. DB9 is the MSB of these 10 bits.
Gain Control Pin. This controls whether the output range from the DAC is 0–VREF or 0–2 VREF.
Asynchronous Active Low Control Input that Clears All Input Registers and DAC Registers to Zeros.
REV. 0
–7–
AD5334/AD5335/AD5336/AD5344
AD5344 PIN CONFIGURATION
AD5344 FUNCTIONAL BLOCK DIAGRAM
VREFA
VDD
VREFB
POWER-ON
RESET
DB. 11
.
...
.
DB0
INPUT
REGISTER
CS
WR
A0
INPUT
REGISTER
AD5344
DAC
REGISTER
DAC
REGISTER
12-BIT
DAC
12-BIT
DAC
BUFFER
VOUTA
INPUT
REGISTER
INPUT
REGISTER
DAC
REGISTER
DAC
REGISTER
12-BIT
DAC
12-BIT
DAC
28
DB11
27
DB10
VREFB 3
26
DB9
VREFA 4
25
DB8
VOUTA 5
24
DB7
23
DB6
VOUTB 6
12-BIT
AD5344
VOUTC 7
22
GND 9
20
DB3
CS 10
19
DB2
WR 11
18
DB1
A0 12
17
DB0
A1 13
16
VDD
LDAC 14
15
PD
DB5
TOP VIEW
VOUTD 8 (Not to Scale) 21 DB4
BUFFER
VOUTB
INTERFACE
LOGIC
A1
VREFD 1
VREFC 2
BUFFER
VOUTC
BUFFER
VOUTD
TO ALL DACS
AND BUFFERS
LDAC
POWER-DOWN
LOGIC
VREFD
PD
VREFC
GND
AD5344 PIN FUNCTION DESCRIPTIONS
Pin
No.
Mnemonic
Function
1
2
3
4
5
6
7
8
9
10
11
12
13
14
VREFD
VREFC
VREFB
VREFA
VOUTA
VOUTB
VOUTC
VOUTD
GND
CS
WR
A0
A1
LDAC
15
16
PD
VDD
17–28
DB0–DB11
Unbuffered Reference Input for DAC D.
Unbuffered Reference Input for DAC C.
Unbuffered Reference Input for DAC B.
Unbuffered Reference Input for DAC A.
Output of DAC A. Buffered output with rail-to-rail operation.
Output of DAC B. Buffered output with rail-to-rail operation.
Output of DAC C. Buffered output with rail-to-rail operation.
Output of DAC D. Buffered output with rail-to-rail operation.
Ground Reference Point for All Circuitry on the Part.
Active Low Chip Select Input. This is used in conjunction with WR to write data to the parallel interface.
Active Low Write Input. This is used in conjunction with CS to write data to the parallel interface.
LSB Address Pin for Selecting which DAC Is to Be Written to.
MSB Address Pin for Selecting which DAC Is to Be Written to.
Active Low Control Input that Updates the DAC Registers with the Contents of the Input Registers.
This allows all DAC outputs to be simultaneously updated.
Power-Down Pin. This active low control pin puts all DACs into power-down mode.
Power Supply Pin. This part can operate from 2.5 V to 5.5 V and the supply should be decoupled with a
10 µF capacitor in parallel with a 0.1 µF capacitor to GND.
12 Parallel Data Inputs. DB11 is the MSB of these 12 bits.
–8–
REV. 0
AD5334/AD5335/AD5336/AD5344
TERMINOLOGY
RELATIVE ACCURACY
GAIN ERROR
AND
OFFSET
ERROR
For the DAC, Relative Accuracy or Integral Nonlinearity (INL)
is a measure of the maximum deviation, in LSBs, from a straight
line passing through the actual endpoints of the DAC transfer
function. Typical INL versus Code plot can be seen in Figures
5, 6, and 7.
ACTUAL
OUTPUT
VOLTAGE
DIFFERENTIAL NONLINEARITY
Differential Nonlinearity (DNL) is the difference between the
measured change and the ideal 1 LSB change between any two
adjacent codes. A specified differential nonlinearity of ± 1 LSB
maximum ensures monotonicity. This DAC is guaranteed monotonic by design. Typical DNL versus Code plot can be seen in
Figures 8, 9, and 10.
IDEAL
POSITIVE
OFFSET
OFFSET ERROR
DAC CODE
This is a measure of the offset error of the DAC and the output
amplifier. It is expressed as a percentage of the full-scale range.
Figure 3. Positive Offset Error and Gain Error
If the offset voltage is positive, the output voltage will still be
positive at zero input code. This is shown in Figure 3. Because
the DACs operate from a single supply, a negative offset cannot
appear at the output of the buffer amplifier. Instead, there will
be a code close to zero at which the amplifier output saturates
(amplifier footroom). Below this code there will be a deadband
over which the output voltage will not change. This is illustrated
in Figure 4.
GAIN ERROR
AND
OFFSET
ERROR
IDEAL
OUTPUT
VOLTAGE
GAIN ERROR
This is a measure of the span error of the DAC (including any
error in the gain of the buffer amplifier). It is the deviation in
slope of the actual DAC transfer characteristic from the ideal
expressed as a percentage of the full-scale range. This is illustrated in Figure 2.
ACTUAL
NEGATIVE
OFFSET
DAC CODE
POSITIVE
GAIN ERROR
ACTUAL
NEGATIVE
GAIN ERROR
DEADBAND CODES
AMPLIFIER
FOOTROOM
(~1mV)
OUTPUT
VOLTAGE
IDEAL
NEGATIVE
OFFSET
DAC CODE
Figure 4. Negative Offset Error and Gain Error
Figure 2. Gain Error
REV. 0
–9–
AD5334/AD5335/AD5336/AD5344
OFFSET ERROR DRIFT
DIGITAL FEEDTHROUGH
This is a measure of the change in Offset Error with changes in
temperature. It is expressed in (ppm of full-scale range)/°C.
This is a measure of the change in Gain Error with changes in
temperature. It is expressed in (ppm of full-scale range)/°C.
Digital Feedthrough is a measure of the impulse injected into
the analog output of the DAC from the digital input pins of the
device but is measured when the DAC is not being written to
(CS held high). It is specified in nV-secs and is measured with a
full-scale change on the digital input pins, i.e. from all 0s to all
1s and vice versa.
DC POWER-SUPPLY REJECTION RATIO (PSRR)
DIGITAL CROSSTALK
This indicates how the output of the DAC is affected by changes in
the supply voltage. PSRR is the ratio of the change in VOUT to a
change in VDD for full-scale output of the DAC. It is measured
in dBs. VREF is held at 2 V and VDD is varied ± 10%.
This is the glitch impulse transferred to the output of one DAC
at midscale in response to a full-scale code change (all 0s to all
1s and vice versa) in the input register of another DAC. It is
expressed in nV secs.
DC CROSSTALK
ANALOG CROSSTALK
This is the dc change in the output level of one DAC at midscale in response to a full-scale code change (all 0s to all 1s and
vice versa) and output change of another DAC. It is expressed
in µV.
This is the glitch impulse transferred to the output of one DAC
due to a change in the output of another DAC. It is measured
by loading one of the input registers with a full-scale code change
(all 0s to all 1s and vice versa) while keeping LDAC high. Then
pulse LDAC low and monitor the output of the DAC whose
digital code was not changed. The area of the glitch is expressed
in nV secs.
GAIN ERROR DRIFT
REFERENCE FEEDTHROUGH
This is the ratio of the amplitude of the signal at the DAC output
to the reference input when the DAC output is not being updated
(i.e., LDAC is high). It is expressed in dBs.
DAC-TO-DAC CROSSTALK
This is a ratio of the amplitude of the signal at the output of one
DAC to a sine wave on the reference inputs of the other DACs.
It is measured by grounding one VREF pin and applying a 10 kHz,
4 V peak-to-peak sine wave to the other VREF pins. It is expressed
in dBs.
This is the glitch impulse transferred to the output of one DAC
due to a digital code change and subsequent output change of
another DAC. This includes both digital and analog crosstalk. It
is measured by loading one of the DACs with a full-scale code
change (all 0s to all 1s and vice versa) with the LDAC pin set
low and monitoring the output of another DAC. The energy of
the glitch is expressed in nV secs.
MAJOR-CODE TRANSITION GLITCH ENERGY
MULTIPLYING BANDWIDTH
Major-Code Transition Glitch Energy is the energy of the
impulse injected into the analog output when the DAC changes
state. It is normally specified as the area of the glitch in nV secs
and is measured when the digital code is changed by 1 LSB at
the major carry transition (011 . . . 11 to 100 . . . 00 or 100 . . . 00
to 011 . . . 11).
The amplifiers within the DAC have a finite bandwidth. The
Multiplying Bandwidth is a measure of this. A sine wave on the
reference (with full-scale code loaded to the DAC) appears on
the output. The Multiplying Bandwidth is the frequency at which
the output amplitude falls to 3 dB below the input.
CHANNEL-TO-CHANNEL ISOLATION
TOTAL HARMONIC DISTORTION
This is the difference between an ideal sine wave and its attenuated
version using the DAC. The sine wave is used as the reference
for the DAC and the THD is a measure of the harmonics present
on the DAC output. It is measured in dBs.
–10–
REV. 0
Typical Performance Characteristics– AD5334/AD5335/AD5336/AD5344
1.0
12
3
TA = 25ⴗC
VDD = 5V
TA = 25ⴗC
VDD = 5V
2
TA = 25ⴗC
VDD = 5V
8
0
INL ERROR – LSBs
INL ERROR – LSBs
INL ERROR – LSBs
0.5
1
0
–1
4
0
–4
–0.5
–8
–2
0
50
100
150
CODE
200
Figure 5. AD5334 Typical INL Plot
0.3
200
400
600
CODE
800
1000
1000
2000
CODE
3000
4000
Figure 7. AD5336 Typical INL Plot
TA = 25ⴗC
VDD = 5V
TA = 25ⴗC
VDD = 5V
DNL ERROR – LSBs
0.4
0
–0.1
–0.2
0.2
0
–0.2
0.5
0
–0.5
–0.4
0
50
100
150
CODE
200
–1
–0.6
250
Figure 8. AD5334 Typical DNL Plot
0
200
800
400
600
CODE
0
1000
Figure 9. AD5335 Typical DNL Plot
0.5
TA = 25ⴗC
0.4
MAX INL
0.3
MIN DNL
4000
0.5
0.2
MAX DNL
0.1
0
–0.1
GAIN ERROR
0
OFFSET ERROR
MIN DNL
–0.2
–0.25
3000
VDD = 5V
VREF = 2V
MAX INL
ERROR – %
ERROR – LSBs
0
2000
CODE
1
VDD = 5V
VREF = 2V
0.25
MAX DNL
1000
Figure 10. AD5336 Typical DNL Plot
0.5
VDD = 5V
ERROR – LSBs
0
1
0.6
0.1
–0.3
–12
0
Figure 6. AD5335 Typical INL Plot
TA = 25ⴗC
VDD = 5V
0.2
DNL ERROR – LSBs
–3
250
DNL ERROR – LSBs
–1.0
–0.5
–0.3
MIN INL
MIN INL
–0.4
–0.5
0
1
2
3
VREF – V
4
Figure 11. AD5334 INL and DNL
Error vs. VREF
REV. 0
5
–0.5
ⴚ40
0
40
80
120
TEMPERATURE – ⴗC
Figure 12. AD5334 INL Error and
DNL Error vs. Temperature
–11–
–1
ⴚ40
0
40
80
120
TEMPERATURE – ⴗC
Figure 13. AD5334 Offset Error
and Gain Error vs. Temperature
AD5334/AD5335/AD5336/AD5344
TA = 25ⴗC
VREF = 2V
0.1
3V SOURCE
400
–0.3
–0.4
IDD – ␮A
VOUT – Volts
–0.2
3
2
OFFSET ERROR
1
VDD = 3.6V
300
TA = 25ⴗC
VREF = 2V
100
3V SINK
5V SINK
0
0
1
2
4
3
VDD – Volts
5
6
Figure 14. Offset Error and Gain
Error vs. VDD
0
1
3
4
2
5
SINK/SOURCE CURRENT – mA
0
ZERO-SCALE
6
FULL SCALE
1800
0.5
TA = 25ⴗC
DAC CODE
Figure 16. Supply Current
vs. DAC Code
Figure 15. VOUT Source and Sink
Current Capability
TA = 25ⴗC
500
1600
0.4
1400
1200
300
0.3
IDD – ␮A
IDD – ␮A
400
IDD – ␮A
VDD = 5.5V
200
–0.5
600
500
GAIN ERROR
–0.1
–0.6
5V SOURCE
4
0
ERROR – %
600
5
0.2
0.2
1000
800
600
200
0.1
100
VDD = 5V
400
VDD = 3V
200
0
2.5
3.0
3.5
4.0
VDD – V
4.5
5.0
Figure 17. Supply Current vs. Supply
Voltage
CH1
0
2.5
5.5
TA = 25
ⴗC
5µs
VDD = 5V
VREF = 5V
0
3.0
3.5
4.0
4.5
VDD – V
5.0
5.5
CH1
1
2
3
VLOGIC – V
4
5
Figure 19. Supply Current
vs. Logic Input Voltage
Figure 18. Power-Down Current vs.
Supply Voltage
VOUTA
0
TA = 25ⴗC
VDD = 5V
VREF = 2V
TA = 25ⴗC
VDD = 5V
VREF = 2V
VDD
CH1
VOUTA
LDAC
VOUTA
CH2
CH2
CH1 1V, CH2 5V, TIME BASE= 1␮s/DIV
Figure 20. Half-Scale Settling (1/4 to
3/4 Scale Code Change)
PD
CH2
CH1 2V, CH2 200mV, TIME BASE = 200␮s/DIV
Figure 21. Power-On Reset to 0 V
–12–
CH1 500mV, CH2 5V, TIME BASE = 1␮s/DIV
Figure 22. Exiting Power-Down
to Midscale
REV. 0
AD5334/AD5335/AD5336/AD5344
0.929
10
0.928
0
0.927
–10
0.926
0.925
–20
dB
VDD = 5V
VOUT – Volts
FREQUENCY
VDD = 3V
0.924
–30
0.923
0.922
–40
0.921
–50
0.920
0.919
300
350
400
450
500
IDD – ␮A
550
–60
0.01
500ns/DIV
600
Figure 23. IDD Histogram with VDD =
3 V and VDD = 5 V
Figure 24. AD5344 Major-Code Transition Glitch Energy
0.1
1
10
100
FREQUENCY – kHz
1k
10k
Figure 25. Multiplying Bandwidth
(Small-Signal Frequency Response)
VDD = 5V
TA = 25ⴗC
0.3
0.2
1mV/DIV
FULL-SCALE ERROR – %FSR
0.4
0.1
0
–0.1
–0.2
0
1
2
3
VREF – V
4
5
6
Figure 26. Full-Scale Error vs. VREF
750ns/DIV
Figure 27. DAC-DAC Crosstalk
FUNCTIONAL DESCRIPTION
The AD5334/AD5335/AD5336/AD5344 are quad resistorstring DACs fabricated on a CMOS process with resolutions of
8, 10, 10, and 12 bits, respectively. They are written to using a
parallel interface. They operate from single supplies of 2.5 V to
5.5 V and the output buffer amplifiers offer rail-to-rail output
swing. The gain of the buffer amplifiers in the AD5334 and
AD5336 can be set to 1 or 2 to give an output voltage range of
0 to VREF or 0 to 2 VREF. The AD5335 and AD5344 have output buffers with unity gain.
where:
D = decimal equivalent of the binary code which is loaded to
the DAC register:
0–255 for AD5334 (8 Bits)
0–1023 for AD5335/AD5336 (10 Bits)
0–4095 for AD5344 (12 Bits)
N = DAC resolution
Gain = Output Amplifier Gain (1 or 2)
The devices have a power-down feature that reduces current
consumption to only 80 nA @ 3 V.
VREF
GAIN
Digital-to-Analog Section
The architecture of one DAC channel consists of a reference
buffer and a resistor-string DAC followed by an output buffer
amplifier. The voltage at the VREF pin provides the reference
voltage for the DAC. Figure 28 shows a block diagram of the
DAC architecture. Since the input coding to the DAC is
straight binary, the ideal output voltage is given by:
VOUT = VREF ×
REV. 0
INPUT
REGISTER
DAC
REGISTER
RESISTOR
STRING
VOUT
OUTPUT
BUFFER AMPLIFIER
Figure 28. Single DAC Channel Architecture
D
× Gain
2N
–13–
AD5334/AD5335/AD5336/AD5344
Access to the DAC register is controlled by the LDAC function.
When LDAC is high, the DAC register is latched and the input
register may change state without affecting the contents of the
DAC register. However, when LDAC is brought low, the DAC
register becomes transparent and the contents of the input
register are transferred to it. The gain control signal is also
double-buffered and is only updated when LDAC is taken low.
Resistor String
The resistor string section is shown in Figure 29. It is simply a
string of resistors, each of value R. The digital code loaded
to the DAC register determines at what node on the string the
voltage is tapped off to be fed into the output amplifier. The
voltage is tapped off by closing one of the switches connecting
the string to the amplifier. Because it is a string of resistors, it is
guaranteed monotonic.
This is useful if the user requires simultaneous updating of all
DACs and peripherals. The user may write to all input registers
individually and then, by pulsing the LDAC input low, all outputs will update simultaneously.
VREF
R
Double-buffering is also useful where the DAC data is loaded in
two bytes, as in the AD5335, because it allows the whole data
word to be assembled in parallel before updating the DAC register.
This prevents spurious outputs that could occur if the DAC
register were updated with only the high byte or the low byte.
R
R
TO OUTPUT
AMPLIFIER
These parts contain an extra feature whereby the DAC register
is not updated unless its input register has been updated since
the last time that LDAC was brought low. Normally, when
LDAC is brought low, the DAC registers are filled with the
contents of the input registers. In the case of the AD5334/
AD5335/AD5336/AD5344, the part will only update the DAC
register if the input register has been changed since the last
time the DAC register was updated. This removes unnecessary
crosstalk.
R
R
Figure 29. Resistor String
DAC Reference Input
The DACs operate with an external reference. The reference
inputs are unbuffered and have an input range of 0.25 V to VDD.
The impedance per DAC is typically 180 kΩ for 0–VREF mode
and 90 kΩ for 0–2 VREF mode. The AD5336 and AD5344 have
separate reference inputs for each DAC, while the AD5334 and
AD5335 have a reference inputs for each pair of DACS (A/B
and C/D).
Clear Input (CLR)
CLR is an active low, asynchronous clear that resets the input and
DAC registers. Note that the AD5344 has no CLR function.
Chip Select Input (CS)
CS is an active low input that selects the device.
Write Input (WR)
WR is an active low input that controls writing of data to the
device. Data is latched into the input register on the rising edge
of WR.
Output Amplifier
The output buffer amplifier is capable of generating output
voltages to within 1 mV of either rail. Its actual range depends
on VREF, GAIN, the load on VOUT, and offset error.
Load DAC Input (LDAC)
LDAC transfers data from the input register to the DAC register
(and hence updates the outputs). Use of the LDAC function
enables double buffering of the DAC and GAIN data. There
are two LDAC modes:
If a gain of 1 is selected (GAIN = 0), the output range is 0.001 V
to VREF.
If a gain of 2 is selected (GAIN = 1), the output range is 0.001 V
to 2 VREF. However because of clamping the maximum output
is limited to VDD – 0.001 V.
Synchronous Mode: In this mode the DAC register is updated
after new data is read in on the rising edge of the WR input.
LDAC can be tied permanently low or pulsed as in Figure 1.
The output amplifier is capable of driving a load of 2 kΩ to
GND or VDD, in parallel with 500 pF to GND or VDD. The
source and sink capabilities of the output amplifier can be seen
in Figure 15.
The slew rate is 0.7 V/µs with a half-scale settling time to ±0.5 LSB
(at 8 bits) of 6 µs with the output unloaded. See Figure 20.
Asynchronous Mode: In this mode the outputs are not updated
at the same time that the input register is written to. When LDAC
goes low the DAC register is updated with the contents of the
input register.
High-Byte Enable Input (HBEN)
PARALLEL INTERFACE
The AD5334, AD5336, and AD5344 load their data as a single
8-, 10-, or 12-bit word, while the AD5335 loads data as a low
byte of 8 bits and a high byte containing 2 bits.
Double-Buffered Interface
The AD5334/AD5335/AD5336/AD5344 DACs all have doublebuffered interfaces consisting of an input register and a DAC
register. DAC data and GAIN inputs (when available) are written
to the input register under control of the Chip Select (CS) and
Write (WR).
High-Byte Enable is a control input on the AD5335 only that
determines if data is written to the high-byte input register or
the low-byte input register.
The low data byte of the AD5335 consists of data bits 0 to 7 at
data inputs DB0 to DB7, while the high byte consists of Data
Bits 8 and 9 at data inputs DB0 and DB1. DB2 to DB7 are
ignored during a high byte write. See Figure 30.
–14–
REV. 0
AD5334/AD5335/AD5336/AD5344
When the PD pin is high, the DACs work normally with a typical
power consumption of 600 µA at 5 V (500 µA at 3 V). In powerdown mode, however, the supply current falls to 200 nA at 5 V
(80 nA at 3 V) when the DACs are powered down. Not only
does the supply current drop, but the output stage is also internally
switched from the output of the amplifier, making it open-circuit.
This has the advantage that the outputs are three-state while
the part is in power-down mode, and provides a defined input
condition for whatever is connected to the outputs of the
DAC amplifiers. The output stage is illustrated in Figure 31.
HIGH BYTE
X
X
X
X
X
X
DB9 DB8
LOW BYTE
DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
X = UNUSED BIT
Figure 30. Data Format For AD5335
POWER-ON RESET
The AD5334/AD5335/AD5336/AD5344 are provided with a
power-on reset function, so that they power up in a defined state.
The power-on state is:
• Normal operation
• 0 – VREF output range
• Output voltage set to 0 V
RESISTOR
STRING DAC
AMPLIFIER
VOUT
POWER-DOWN
CIRCUITRY
Both input and DAC registers are filled with zeros and remain
so until a valid write sequence is made to the device. This is
particularly useful in applications where it is important to know
the state of the DAC outputs while the device is powering up.
Figure 31. Output Stage During Power-Down
The bias generator, the output amplifier, the resistor string, and
all other associated linear circuitry are all shut down when the
power-down mode is activated. However, the contents of the
registers are unaffected when in power-down. The time to exit
power-down is typically 2.5 µs for VDD = 5 V and 5 µs when
VDD = 3 V. This is the time from a rising edge on the PD pin
to when the output voltage deviates from its power-down voltage. See Figure 22.
POWER-DOWN MODE
The AD5334/AD5335/AD5336/AD5344 have low power consumption, dissipating typically 1.5 mW with a 3 V supply and
3 mW with a 5 V supply. Power consumption can be further
reduced when the DACs are not in use by putting them into
power-down mode, which is selected by taking pin PD low.
Table I. AD5334/AD5336/AD5344 Truth Table
CLR
LDAC
CS
WR
A1
A0
Function
1
1
0
1
1
1
1
1
1
1
X
1
1
1
1
0
1
X
X
0
0
0
0
X
X
1
X
0➝1
0➝1
0➝1
0➝1
X
X
X
X
0
0
1
1
X
X
X
X
0
1
0
1
X
No Data Transfer
No Data Transfer
Clear All Registers
Load DAC A Input Register, GAIN A (AD5334/AD5336)
Load DAC B Input Register, GAIN B (AD5334/AD5336)
Load DAC C Input Register, GAIN C (AD5334/AD5336)
Load DAC D Input Register, GAIN D (AD5334/AD5336)
Update DAC Registers
X = don’t care.
Table II. AD5335 Truth Table
CLR
LDAC
CS
WR
A1
A0
HBEN
Function
1
1
0
1
1
1
1
1
1
1
1
1
1
1
X
1
1
1
1
1
1
1
1
0
1
X
X
0
0
0
0
0
0
0
0
X
X
1
X
0➝1
0➝1
0➝1
0➝1
0➝1
0➝1
0➝1
0➝1
X
X
X
X
0
0
0
0
1
1
1
1
X
X
X
X
0
0
1
1
0
0
1
1
X
X
X
X
0
1
0
1
0
1
0
1
X
No Data Transfer
No Data Transfer
Clear All Registers
Load DAC A Low Byte Input Register
Load DAC A High Byte Input Register
Load DAC B Low Byte Input Register
Load DAC B High Byte Input Register
Load DAC C Low Byte Input Register
Load DAC C High Byte Input Register
Load DAC D Low Byte Input Register
Load DAC D High Byte Input Register
Update DAC Registers
X = don’t care.
REV. 0
–15–
AD5334/AD5335/AD5336/AD5344
SUGGESTED DATABUS FORMATS
6V TO 16V
In many applications the GAIN input of the AD5334 and
AD5336 may be hard-wired. However, if more flexibility is
required, it can be included in a data bus. This enables the user
to software program GAIN, giving the option of doubling the
resolution in the lower half of the DAC range. In a bused system
GAIN may be treated as a data input since it is written to the
device during a write operation and takes effect when LDAC is
taken low. This means that the output amplifier gain of multiple
DAC devices can be controlled using a common GAIN line.
0.1␮F
VIN
ADM663/ADM666
VOUT(2)
VSET GND SHDN
X
X
Figure 34. Using an ADM663/ADM666 as Power and
Reference to AD5334/AD5335/AD5336/AD5344
GAIN DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
Bipolar Operation Using the AD5334/AD5335/AD5336/AD5344
X = UNUSED BIT
The AD5334/AD5335/AD5336/AD5344 have been designed
for single supply operation, but bipolar operation is achievable
using the circuit shown in Figure 35. The circuit shown has been
configured to achieve an output voltage range of –5 V < VO <
+5 V. Rail-to-rail operation at the amplifier output is achievable
using an AD820 or OP295 as the output amplifier.
Figure 32. AD5336 Data Format for Byte Load with GAIN
Data on 8-Bit Bus
APPLICATIONS INFORMATION
Typical Application Circuits
The AD5334/AD5335/AD5336/AD5344 can be used with a
wide range of reference voltages and offer full, one-quadrant
multiplying capability over a reference range of 0.25 V to VDD.
More typically, these devices may be used with a fixed, precision reference voltage. Figure 33 shows a typical setup for the
devices when using an external reference connected to the reference inputs. Suitable references for 5 V operation are the AD780
and REF192. For 2.5 V operation, a suitable external reference
would be the AD589, a 1.23 V bandgap reference.
The output voltage for any input code can be calculated as
follows:
VO = [(1 + R4/R3) × (R2/(R1 + R2) × (2 × VREF × D/2N)] – R4 × VREF/R3
where:
D is the decimal equivalent of the code loaded to the DAC, N is
DAC resolution and VREF is the reference voltage input.
With:
VREF = 2.5 V
R1 = R3 = 10 kΩ
R2 = R4 = 20 kΩ and VDD = 5 V.
VOUT = (10 × D/2N) – 5
VDD = 2.5V TO 5.5V
0.1␮F
10␮F
VIN
EXT
REF
VOUT*
AD5334/AD5335/
AD5336/AD5344
*ONLY ONE CHANNEL OF VREF AND VOUT SHOWN
AD5336
X
VREF*
0.1␮F
GND
Examples of data formats for putting GAIN on a 16-bit databus
are shown in Figure 32. Note that any unused bits above the
actual DAC data may be used for GAIN.
X
VDD
SENSE
The AD5336 databus must be at least 10 bits wide and is best
suited to a 16-bit databus system.
X
10␮F
VDD = 5V
VDD
VOUT
GND
VREF*
R4
20k⍀
VOUT*
AD5334/AD5335/
AD5336/AD5344
AD780/REF192
WITH VDD = 5V
OR
AD589 WITH VDD = 2.5V
0.1␮F
10␮F
+5V
R3
10k⍀
ⴞ5V
VIN
GND
VDD
EXT
REF
*ONLY ONE CHANNEL OF VREF AND VOUT SHOWN
GND
Figure 33. AD5334/AD5335/AD5336/AD5344 Using
External Reference
VREF*
VOUT
0.1␮F
AD5334/AD5335/
AD5336/AD5344
VOUT*
AD780/REF192
WITH VDD = 5V
OR
AD589 WITH VDD = 2.5V
Driving VDD from the Reference Voltage
If an output range of zero to V DD is required, the simplest
solution is to connect the reference inputs to VDD. As this supply
may not be very accurate, and may be noisy, the devices
may be powered from the reference voltage, for example
using a 5 V reference such as the ADM663 or ADM666,
as shown in Figure 34.
–5V
R1
10k⍀
R2
20k⍀
GND
*ONLY ONE CHANNEL OF VREF AND VOUT SHOWN
Figure 35. Bipolar Operation using the AD5334/AD5335/
AD5336/AD5344
–16–
REV. 0
AD5334/AD5335/AD5336/AD5344
Decoding Multiple AD5334/AD5335/AD5336/AD5344
The CS pin on these devices can be used in applications to decode
a number of DACs. In this application, all DACs in the system
receive the same data and WR pulses, but only the CS to one of
the DACs will be active at any one time, so data will only be
written to the DAC whose CS is low. If multiple AD5343s are
being used, a common HBEN line will also be required to
determine if the data is written to the high-byte or low-byte
register of the selected DAC.
used for some other purpose. The AD5336 and AD5344 have
separate reference inputs for each DAC.
The upper and lower limits for the test are loaded to DACs A
and B which, in turn, set the limits on the CMP04. If a signal at
the VIN input is not within the programmed window, an LED
will indicate the fail condition.
5V
0.1␮F
VDD
1G
ENABLE
CODED
ADDRESS
VCC
1Y0
1A
1Y1
74HC139
1B
1Y2
1Y3
DGND
AD5334/AD5335/
AD5336/AD5344
A1
A0
HBEN*
WR
DATA
INPUTS
LDAC
CLR
CS
AD5334/AD5335/
AD5336/AD5344
A1
A0
HBEN*
WR
LDAC
CLR
CS
1k⍀
PASS
VDD
VREFA
VOUTA
VREFB
PASS/
FAIL
1/2
CMP04
AD5336/AD5344
VOUTB
1/6 74HC05
GND
Programmable Current Source
DATA BUS
AD5334/AD5335/
AD5336/AD5344
A1
A0
HBEN*
WR
DATA
INPUTS
LDAC
CLR
CS
VREF
1k⍀
FAIL
Figure 37. Programmable Window Detector
AD5334/AD5335/
AD5336/AD5344
A1
A0
HBEN*
WR
DATA
LDAC
INPUTS
CLR
CS
A0
A1
HBEN
WR
LDAC
CLR
10␮F
VIN
The 74HC139 is used as a 2- to 4-line decoder to address any
of the DACs in the system. To prevent timing errors from occurring, the enable input should be brought to its inactive state
while the coded address inputs are changing state. Figure 36 shows
a diagram of a typical setup for decoding multiple devices in a
system. Once data has been written sequentially to all DACs in
a system, all the DACs can be updated simultaneously using a
common LDAC line. A common CLR line can also be used to
reset all DAC outputs to zero (except on the AD5344).
Figure 38 shows the AD5334/AD5335/AD5336/AD5344 used
as the control element of a programmable current source. In this
example, the full-scale current is set to 1 mA. The output voltage from the DAC is applied across the current setting resistor
of 4.7 kΩ in series with the 470 Ω adjustment potentiometer,
which gives an adjustment of about ± 5%. Suitable transistors to
place in the feedback loop of the amplifier include the BC107
and the 2N3904, which enable the current source to operate
from a minimum VSOURCE of 6 V. The operating range is determined by the operating characteristics of the transistor. Suitable
amplifiers include the AD820 and the OP295, both having railto-rail operation on their outputs. The current for any digital
input code and resistor value can be calculated as follows:
D
I = G × VREF × N
mA
(2 × R)
Where:
G is the gain of the buffer amplifier (1 or 2)
D is the digital input code
N is the DAC resolution (8, 10, or 12 bits)
R is the sum of the resistor plus adjustment potentiometer in kΩ
DATA
INPUTS
VDD = 5V
*AD5335 ONLY
0.1␮F
10␮F
VSOURCE
Figure 36. Decoding Multiple DAC Devices
VIN
AD5334/AD5335/AD5336/AD5344 as a Digitally Programmable
Window Detector
A digitally programmable upper/lower limit detector using two
of the DACs in the AD5334/AD5335/AD5336/AD5344 is
shown in Figure 37.
VREF*
VOUT
GND
0.1␮F
LOAD
VOUT*
AD5334/AD5335/
AD5336/AD5344
AD820/
OP295
AD780/REF192
WITH VDD = 5V
Any pair of DACs in the device may be used, but for simplicity
the description will refer to DACs A and B.
4.7k⍀
GND
470⍀
Care must be taken to connect the correct reference inputs to
the reference source. The AD5334 and AD5335 have only two
reference inputs, VREFA/B for DACs A and B and VREFC/D for
DACs C and D. If DACs A and B are used (for example) then
only VREFA/B is needed. DACs C and D and VREFC/D may be
REV. 0
5V
VDD
EXT
REF
*ONLY ONE CHANNEL OF VREF AND VOUT SHOWN
Figure 38. Programmable Current Source
–17–
AD5334/AD5335/AD5336/AD5344
Coarse and Fine Adjustment Using the AD5334/AD5335/
AD5336/AD5344
Power Supply Bypassing and Grounding
Two of the DACs in the AD5334/AD5335/AD5336/AD5344 can
be paired together to form a coarse and fine adjustment function,
as shown in Figure 39. As with the window comparator previously described, the description will refer to DACs A, and B and
the reference connections will depend on the actual device used.
DAC A is used to provide the coarse adjustment while DAC B
provides the fine adjustment. Varying the ratio of R1 and R2 will
change the relative effect of the coarse and fine adjustments. With
the resistor values shown the output amplifier has unity gain for
the DAC A output, so the output range is zero to (VREF – 1 LSB).
For DAC B the amplifier has a gain of 7.6 × 10–3, giving DAC B
a range equal to 2 LSBs of DAC A.
The circuit is shown with a 2.5 V reference, but reference voltages up to VDD may be used. The op amps indicated will allow a
rail-to-rail output swing.
VDD = 5V
0.1␮F
10␮F
R4
390⍀
5V
VDD
VIN
EXT
REF
R3
51.2k⍀
VOUT
VOUTA
VOUT
VREFA
R1
390⍀
0.1␮F
GND
AD5336/AD5344
VOUTB
AD780/REF192
WITH VDD = 5V
R2
51.2k⍀
VREFB
GND
In any circuit where accuracy is important, careful consideration
of the power supply and ground return layout helps to ensure
the rated performance. The printed circuit board on which the
AD5334/AD5335/AD5336/AD5344 is mounted should be
designed so that the analog and digital sections are separated,
and confined to certain areas of the board. If the device is in a
system where multiple devices require an AGND-to-DGND
connection, the connection should be made at one point only.
The star ground point should be established as closely as possible to the device. The AD5334/AD5335/AD5336/AD5344
should have ample supply bypassing of 10 µF in parallel with
0.1 µF on the supply located as close to the package as possible,
ideally right up against the device. The 10 µF capacitors are the
tantalum bead type. The 0.1 µF capacitor should have low
Effective Series Resistance (ESR) and Effective Series Inductance
(ESI), like the common ceramic types that provide a low impedance path to ground at high frequencies to handle transient
currents due to internal logic switching.
The power supply lines of the device should use as large a trace
as possible to provide low impedance paths and reduce the
effects of glitches on the power supply line. Fast switching signals such as clocks should be shielded with digital ground to
avoid radiating noise to other parts of the board, and should
never be run near the reference inputs. Avoid crossover of digital
and analog signals. Traces on opposite sides of the board should
run at right angles to each other. This reduces the effects of
feedthrough through the board. A microstrip technique is by
far the best, but not always possible with a double-sided board.
In this technique, the component side of the board is dedicated
to ground plane while signal traces are placed on the solder side.
Figure 39. Coarse and Fine Adjustment
–18–
REV. 0
AD5334/AD5335/AD5336/AD5344
Table III. Overview of AD53xx Parallel Devices
Part No.
Resolution DNL
VREF Pins
Settling Time
SINGLES
AD5330
AD5331
AD5340
AD5341
8
10
12
12
± 0.25
± 0.5
± 1.0
± 1.0
1
1
1
1
6 µs
7 µs
8 µs
8 µs
DUALS
AD5332
AD5333
AD5342
AD5343
8
10
12
12
± 0.25
± 0.5
± 1.0
± 1.0
2
2
2
1
6 µs
7 µs
8 µs
8 µs
QUADS
AD5334
AD5335
AD5336
AD5344
8
10
10
12
± 0.25
± 0.5
± 0.5
± 1.0
2
2
4
4
6 µs
7 µs
7 µs
8 µs
Additional Pin Functions
BUF
✓
✓
✓
GAIN
✓
✓
✓
✓
✓
✓
✓
✓
✓
✓
Package
Pins
✓
CLR
✓
✓
✓
✓
TSSOP
TSSOP
TSSOP
TSSOP
20
20
24
20
✓
✓
✓
✓
✓
TSSOP
TSSOP
TSSOP
TSSOP
20
24
28
20
✓
✓
✓
TSSOP
TSSOP
TSSOP
TSSOP
24
24
28
28
HBEN
✓
Table IV. Overview of AD53xx Serial Devices
Part No.
Resolution
No. of DACS
DNL
Interface
Settling Time
Package
Pins
SINGLES
AD5300
AD5310
AD5320
8
10
12
1
1
1
± 0.25
± 0.5
± 1.0
SPI
SPI
SPI
4 µs
6 µs
8 µs
SOT-23, MicroSOIC
SOT-23, MicroSOIC
SOT-23, MicroSOIC
6, 8
6, 8
6, 8
AD5301
AD5311
AD5321
8
10
12
1
1
1
± 0.25
± 0.5
± 1.0
2-Wire
2-Wire
2-Wire
6 µs
7 µs
8 µs
SOT-23, MicroSOIC
SOT-23, MicroSOIC
SOT-23, MicroSOIC
6, 8
6, 8
6, 8
DUALS
AD5302
AD5312
AD5322
8
10
12
2
2
2
± 0.25
± 0.5
± 1.0
SPI
SPI
SPI
6 µs
7 µs
8 µs
MicroSOIC
MicroSOIC
MicroSOIC
8
8
8
AD5303
AD5313
AD5323
8
10
12
2
2
2
± 0.25
± 0.5
± 1.0
SPI
SPI
SPI
6 µs
7 µs
8 µs
TSSOP
TSSOP
TSSOP
16
16
16
QUADS
AD5304
AD5314
AD5324
8
10
12
4
4
4
± 0.25
± 0.5
± 1.0
SPI
SPI
SPI
6 µs
7 µs
8 µs
MicroSOIC
MicroSOIC
MicroSOIC
10
10
10
AD5305
AD5315
AD5325
8
10
12
4
4
4
± 0.25
± 0.5
± 1.0
2-Wire
2-Wire
2-Wire
6 µs
7 µs
8 µs
MicroSOIC
MicroSOIC
MicroSOIC
10
10
10
AD5306
AD5316
AD5326
8
10
12
4
4
4
± 0.25
± 0.5
± 1.0
2-Wire
2-Wire
2-Wire
6 µs
7 µs
8 µs
TSSOP
TSSOP
TSSOP
16
16
16
AD5307
AD5317
AD5327
8
10
12
4
4
4
± 0.25
± 0.5
± 1.0
SPI
SPI
SPI
6 µs
7 µs
8 µs
TSSOP
TSSOP
TSSOP
16
16
16
Visit our web-page at http://www.analog.com/support/standard_linear/selection_guides/AD53xx.html
REV. 0
–19–
AD5334/AD5335/AD5336/AD5344
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
C3830–2.5–4/00 (rev. 0)
24-Lead Thin Shrink Small Outline Package TSSOP
(RU-24)
0.311 (7.90)
0.303 (7.70)
24
13
0.177 (4.50)
0.169 (4.30)
0.256 (6.50)
0.246 (6.25)
1
12
PIN 1
0.006 (0.15)
0.002 (0.05)
SEATING
PLANE
0.0433 (1.10)
MAX
0.0256 (0.65) 0.0118 (0.30)
BSC
0.0075 (0.19)
0.0079 (0.20)
0.0035 (0.090)
8ⴗ
0ⴗ
0.028 (0.70)
0.020 (0.50)
28-Lead Thin Shrink Small Outline Package TSSOP
(RU-28)
0.386 (9.80)
0.378 (9.60)
28
15
0.177 (4.50)
0.169 (4.30)
0.256 (6.50)
0.246 (6.25)
1
14
PIN 1
0.006 (0.15)
0.002 (0.05)
0.0256 (0.65)
BSC
0.0118 (0.30)
0.0075 (0.19)
0.0079 (0.20)
0.0035 (0.090)
8ⴗ
0ⴗ
0.028 (0.70)
0.020 (0.50)
PRINTED IN U.S.A.
SEATING
PLANE
0.0433 (1.10)
MAX
–20–
REV. 0
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