19-4744; Rev 1; 7/09
Two-/Four-Channel, I
2
C, 7-Bit Sink/Source
Current DAC
General Description
The DS4422 and DS4424 contain two or four I
2
C pro-
grammable current DACs that are each capable of
sinking and sourcing current up to 200µA. Each DAC
output has 127 sink and 127 source settings that are
programmed using the I
2
C interface. The current DAC
outputs power up in a high-impedance state.
♦
Full-Scale Current 50µA to 200µA
♦
Full-Scale Range for Each DAC Determined by
External Resistors
♦
127 Settings Each for Sink and Source Modes
♦
I
2
C-Compatible Serial Interface
♦
Two Address Pins Allow Four Devices on Same
I
2
C Bus
♦
Low Cost
♦
Small Package (14-Pin, 3mm x 3mm TDFN)
♦
-40°C to +85°C Temperature Range
♦
2.7V to 5.5V Operating Range
Features
♦
Two (DS4422) or Four (DS4424) Current DACs
DS4422/DS4424
Applications
Power-Supply Adjustment
Power-Supply Margining
Adjustable Current Sink or Source
Ordering Information
PART
DS4422N+
DS4422N+T&R
DS4424N+
DS4424N+T&R
OUTPUTS
2
2
4
4
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
14 TDFN-EP
14 TDFN-EP
14 TDFN-EP
14 TDFN-EP
Pin Configuration appears at end of data sheet.
+Denotes
a lead(Pb)-free/RoHS-compliant package.
T&R = Tape and reel.
EP = Exposed pad.
Typical Operating Circuit
V
CC
V
OUT0
V
OUT1
R
PU
R
PU
SDA
SCL
A1
A0
GND
V
CC
DC-DC
CONVERTER
OUT
R
0A
FB
R
0B
DC-DC
CONVERTER
FB
R
1B
OUT
R
1A
DS4422/
DS4424
OUT0
OUT1
FS0
R
FS0
FS1
R
FS1
_______________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
Two-/Four-Channel, I
2
C, 7-Bit Sink/Source
Current DAC
DS4422/DS4424
ABSOLUTE MAXIMUM RATINGS
Voltage Range on V
CC
, SDA, and SCL
Relative to Ground.............................................-0.5V to +6.0V
Voltage Range on A0, A1, FS0, FS1, FS2, FS3,
OUT0, OUT1, OUT2, and OUT3 Relative to
Ground ................-0.5V to (V
CC
+ 0.5V) (Not to exceed 6.0V.)
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-55°C to +125°C
Soldering Temperature ...............................Refer to the IPC/JEDEC
J-STD-020 Specification.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS
(T
A
= -40°C to +85°C.)
PARAMETER
Supply Voltage
Input Logic 1 (SDA, SCL, A0, A1)
Input Logic 0 (SDA, SCL, A0, A1)
Full-Scale Resistor Values
SYMBOL
V
CC
V
IH
V
IL
R
FS0
, R
FS1
,
(Note 2)
R
FS2
, R
FS3
(Note 1)
CONDITIONS
MIN
2.7
0.7 x V
CC
-0.3
40
TYP
MAX
5.5
V
CC
+ 0.3
0.3 x V
CC
160
UNITS
V
V
V
k
DC ELECTRICAL CHARACTERISTICS
(V
CC
= +2.7V to +5.5V, T
A
= -40°C to +85°C.)
PARAMETER
Supply Current
Input Leakage (SDA, SCL)
Output Leakage (SDA)
Output Current Low (SDA)
RFS Voltage
I/O Capacitance
SYMBOL
I
CC
I
IL
I
L
I
OL
V
RFS
C
I/O
V
OL
= 0.4V
V
OL
= 0.6V
3
6
0.976
10
V
CC
= 5.5V
(Note 3)
V
CC
= 5.5V
CONDITIONS
DS4422
DS4424
MIN
TYP
MAX
250
250
1
1
UNITS
μA
μA
μA
mA
V
pF
OUTPUT CURRENT SOURCE CHARACTERISTICS
(V
CC
= +2.7V to +5.5V, TA = -40°C to +85°C.)
PARAMETER
Output Voltage for Sinking Current
Output Voltage for Sourcing
Current
Full-Scale Sink Output Current
Output Current Full-Scale
Accuracy
Output Current Temperature
Coefficient
SYMBOL
V
OUT:SINK
(Note 4)
CONDITIONS
MIN
0.5
0
50
-200
TYP
MAX
3.5
V
CC
-
0.75
200
-50
±6
±75
UNITS
V
V
μA
μA
%
ppm/°C
V
OUT:SOURCE
(Note 4)
I
OUT:SINK
(Notes 1, 4)
+25°C, V
CC
= 3.3V; using 0.1% R
FS
resistor (Note 2), V
OUT0
= V
OUT1
= 1.2V
(Note 5)
Full-Scale Source Output Current I
OUT:SOURCE
(Notes 1, 4)
I
OUT:FS
I
OUT:TC
2
_______________________________________________________________________________________
Two-/Four-Channel, I
2
C, 7-Bit Sink/Source
Current DAC
OUTPUT CURRENT SOURCE CHARACTERISTICS (continued)
(V
CC
= +2.7V to +5.5V, TA = -40°C to +85°C.)
PARAMETER
Output Current Variation Due to
Power-Supply Change
Output Current Variation Due to
Output-Voltage Change
Output Leakage Current at Zero
Current Setting
Output Current Differential
Linearity
Output Current Integral Linearity
I
ZERO
DNL
INL
(Notes 6, 7)
(Notes 7, 8)
SYMBOL
DC source
DC sink
DC source, V
OUT
measure at 1.2V
DC sink, V
OUT
measure at 1.2V
-1
-0.5
-1
CONDITIONS
MIN
TYP
0.32
0.42
0.16
0.16
+1
+0.5
+1
MAX
UNITS
%/V
%/V
μA
LSB
LSB
DS4422/DS4424
AC ELECTRICAL CHARACTERISTICS
(V
CC
= +2.7V to +5.5V, T
A
= -40°C to +85°C.)
PARAMETER
SCL Clock Frequency
Bus Free Time Between STOP
and START Conditions
Hold Time (Repeated) START
Condition
Low Period of SCL
High Period of SCL
Data Hold Time
Data Setup Time
START Setup Time
SDA and SCL Rise Time
SDA and SCL Fall Time
STOP Setup Time
SDA and SCL Capacitive
Loading
SYMBOL
f
SCL
t
BUF
t
HD:STA
t
LOW
t
HIGH
t
DH:DAT
t
SU:DAT
t
SU:STA
t
R
t
F
t
SU:STO
C
B
(Note 10)
(Note 10)
(Note 10)
(Note 9)
CONDITIONS
MIN
0
1.3
0.6
1.3
0.6
0
100
0.6
20 + 0.1C
B
20 + 0.1C
B
0.6
400
300
300
0.9
TYP
MAX
400
UNITS
kHz
μs
μs
μs
μs
μs
ns
μs
ns
ns
μs
pF
Note 1:
Note 2:
Note 3:
All voltages with respect to ground. Currents entering the IC are specified positive, and currents exiting the IC are negative.
Input resistors (R
FS
) must be between the speciifed values to ensure the device meets its accuracy and linearity specifications.
Supply current specified with all outputs set to zero current setting. A0 and A1 are connected to GND. SDA and SCL are con-
nected to V
CC
. Excludes current through R
FS
resistors (I
RFS
). Total current including I
RFS
is I
CC
+ (2 x I
RFS
).
Note 4:
The output-voltage range must be satisfied to ensure the device meets its accuracy and linearity specifications.
Note 5:
Temperature drift excludes drift caused by external resistor.
Note 6:
Differential linearity is defined as the difference between the expected incremental current increase with respect to position
and the actual increase. The expected incremental increase is the full-scale range divided by 127.
Note 7:
Guaranteed by design.
Note 8:
Integral linearity is defined as the difference between the expected value as a function of the setting and the actual value.
The expected value is a straight line between the zero and the full-scale values proportional to the setting.
Note 9:
Timing shown is for fast-mode (400kHz) operation. This device is also backward compatible with I
2
C standard-mode timing.
Note 10:
C
B
—total capacitance of one bus line in pF.
_______________________________________________________________________________________
3
Two-/Four-Channel, I
2
C, 7-Bit Sink/Source
Current DAC
DS4422/DS4424
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
DS4422/4 toc01
SUPPLY CURRENT
vs. TEMPERATURE
DS4422/4 toc02
VOLTCO (SOURCE)
40kΩ LOAD ON FS0, FS1, FS2, AND FS3
-175
I
OUT
(μA)
DS4422/4 toc03
250
250
V
CC
= 5.0V
200
SUPPLY CURRENT (μA)
-150
200
SUPPLY CURRENT (μA)
150
150
V
CC
= 3.3V
V
CC
= 2.7V
100
DOES NOT INCLUDE CURRENT DRAWN BY
RESISTORS CONNECTED TO FS0, FS1, FS2,
OR FS3
-200
100
DOES NOT INCLUDE CURRENT DRAWN BY
RESISTORS CONNECTED TO FS0, FS1, FS2,
OR FS3
-225
50
50
0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
SUPPLY VOLTAGE (V)
0
-40
-20
0
20
40
60
80
TEMPERATURE (°C)
-250
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
V
OUT
(V)
VOLTCO (SINK)
DS4422/4 toc04
TEMPERATURE COEFFICIENT
vs. SETTING (SOURCE)
DS4422/4 toc05
TEMPERATURE COEFFICIENT
vs. SETTING (SINK)
TEMPERATURE COEFFICIENT (°C/ppm)
+25°C TO -40°C
0
-50
-100
-150
-200
-250
DS4422/4 toc06
250
40kΩ LOAD ON FS0, FS1, FS2, AND FS3
225
I
OUT
(μA)
200
TEMPERATURE COEFFICIENT (°C/ppm)
150
100
50
0
-50
-100
FOR THE 50μA TO 200μA CURRENT SOURCE
RANGE
50
+25°C TO -40°C
+25°C TO +85°C
200
175
+25°C TO +85°C
150
0
0.5
1.0
1.5
2.0
V
OUT
(V)
2.5
3.0
3.5
4.0
FOR THE 50μA TO 200μA CURRENT SINK
RANGE
0
25
50
75
100
125
0
25
50
75
100
125
SETTING (DEC)
SETTING (DEC)
INTEGRAL LINEARITY
DS4422/4 toc07
DIFFERENTIAL LINEARITY
0.8
0.6
0.4
DNL (LSB)
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
FOR THE 50μA TO 200μA CURRENT SOURCE
AND SINK RANGE
DS4422/4 toc08
1.00
0.75
0.50
INL (LSB)
0.25
0
-0.25
-0.50
-0.75
-1.00
0
25
50
75
100
FOR THE 50μA TO 200μA CURRENT SOURCE
AND SINK RANGE
1.0
125
0
25
50
75
100
125
SETTING (DEC)
SETTING (DEC)
4
_______________________________________________________________________________________
Two-/Four-Channel, I
2
C, 7-Bit Sink/Source
Current DAC
Pin Description
PIN
DS4424
1
2
3
4
5
6
7
8
10
12
14
9, 11
13
—
—
DS4422
1
2
3
—
—
6
7
8
10
—
—
9, 11
13
4, 5, 12,
14
—
NAME
SDA
SCL
GND
FS3
FS2
FS1
FS0
OUT0
OUT1
OUT2
OUT3
A0, A1
V
CC
N.C.
EP
Address Select Inputs. Determines the I
2
C slave address by connecting V
CC
or GND.
See the
Detailed Description
section for the available device addresses.
Power Supply
No Connection
Exposed Pad. Connect to GND or leave unconnected.
Current Output. Sinks or sources the current determined by the I
2
C interface and the
resistance connected to FSx. (The DS4422 has only two outputs: OUT0 and OUT1.)
Full-Scale Calibration Input. A resistor to ground on these pins determines the full-scale
current for each output. FS0 controls OUT0, FS1 controls OUT1, etc. (The DS4422 has
only two inputs: FS0 and FS1.)
FUNCTION
I
2
C Serial Data. Input/output for I
2
C data.
I
2
C Serial Clock. Input for I
2
C clock.
Ground
DS4422/DS4424
Block Diagram
SDA SCL
A1
A0
V
CC
I
2
C-COMPATIBLE
SERIAL INTERFACE
DS4422/DS4424
V
CC
F8h
SOURCE OR
SINK MODE
GND
CURRENT
DAC0
F9h
127 POSITIONS
EACH FOR SINK
AND SOURCE
MODE
FAh
FBh
CURRENT
DAC1
CURRENT
DAC2
CURRENT
DAC3
FS0
R
FS0
OUT0
FS1
R
FS1
OUT1
FS2
R
FS2
OUT2
FS3
R
FS3
OUT3
DS4424 ONLY
_______________________________________________________________________________________
5
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