Rainbow Electronics DS4426 - Manual

General Description
The DS4426 contains four I 2 C-adjustable current DACs
capable of sinking or sourcing current. External resis-
tors set the full-scale range of each output. Each DAC
output has 127 sink and 127 source steps that are pro-
grammed by the I
2 C interface. Power-supply tracking
functionality is provided for three channels using dedi-
cated control inputs. Once power-supply tracking is
accomplished, the current outputs default to zero. Two
address pins allow up to four DS4426 devices to exist
on the same I
2 C bus.
Applications
Power-Supply Adjustment
Power-Supply Margining
Power-Supply Tracking
Adjustable Current Sink or Source
Features
♦ Four Current DACs
50µA to 200µA Adjustable Full-Scale Range
127 Settings Each for Sink and Source
♦ Power-Supply Tracking
Power-Supply Sequencing
Ramp-Up and Ramp-Down Tracking Control
Ratiometric Tracking Support
♦ +2.7V to +5.5V Operation
♦ I
2 C-Compatible Serial Interface
♦ Two Address Input Pins Allow Up to Four Devices
on Same I 2 C Bus
♦ Lead-Free, 28-Pin TQFN Package (4mm x 4mm)
with Exposed Pad
♦ Industrial Temperature Range: -40°C to +85°C
DS4426
Quad-Channel, I
2
C-Margining IDACs with
Three Channels of Power-Supply Tracking
________________________________________________________________ Maxim Integrated Products 1
26
27
25
24
10
9
11
SCL
OUT0 OUT1 OUT2 OUT3
12
SDA
THR1 DNC THR3 FS0 INN3 INP3
1 2
GAIN3
4 5 6 7
20 21 19 17 16 15
GAIN2
GAIN1
INN1
INP1
A1
A0
V
CC
THR2
3
18
28 8 N.C. GND
FS3
23 13 INP2 FS2
22 14 INN2 FS1
THIN QFN
(4mm × 4mm)
TOP VIEW
DS4426
*EP
*EXPOSED PAD.
+
Pin Configuration Ordering Information
19-4541; Rev 1; 7/09
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.
+ Denotes a lead(Pb)-free/RoHS-compliant package.
T&R = Tape and reel.
*
EP = Exposed pad.
PART TEMP RANGE PIN-PACKAGE
DS4426T+ -40°C to +85°C 28 TQFN-EP*
DS4426T+T&R -40°C to +85°C 28 TQFN-EP*
Functional Diagram appears at end of data sheet.