LTC1661
Micropower Dual
10-Bit DAC in MSOP
FEATURES
DESCRIPTION
Tiny: Two 10-Bit DACs in an 8-Lead MSOP—
Half the Board Space of an SO-8
n Micropower: 60µA per DAC
Sleep Mode: 1µA for Extended Battery Life
n Rail-to-Rail Voltage Outputs Drive 1000pF
n Wide 2.7V to 5.5V Supply Range
n Double Buffered for Independent or Simultaneous
DAC Updates
n Reference Range Includes Supply for Ratiometric
0V-to-VCC Output
n Reference Input Has Constant Impedance over All
Codes (260kΩ Typ)—Eliminates External Buffers
n 3-Wire Serial Interface with Schmitt Trigger Inputs
n Differential Nonlinearity: ≤±0.75LSB Max
The LTC®1661 integrates two accurate, serially addressable, 10-bit digital-to-analog converters (DACs) in a single
tiny MS8 package. Each buffered DAC draws just 60µA
total supply current, yet is capable of supplying DC output
currents in excess of 5mA and reliably driving capacitive
loads up to 1000pF Sleep mode further reduces total
.
supply current to a negligible 1µA.
n
APPLICATIONS
n
n
n
n
n
Mobile Communications
Digitally Controlled Amplifiers and Attenuators
Portable Battery-Powered Instruments
Automatic Calibration for Manufacturing
Remote Industrial Devices
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
Linear Technology’s proprietary, inherently monotonic
voltage interpolation architecture provides excellent linearity while allowing for an exceptionally small external
form factor. The double-buffered input logic provides
simultaneous update capability and can be used to write
to either DAC without interrupting sleep mode.
Ultralow supply current, power-saving sleep mode and
extremely compact size make the LTC1661 ideal for
battery-powered applications, while its straightforward
usability, high performance and wide supply range make
it an excellent choice as a general purpose converter.
For additional outputs and even greater board density,
please refer to the LTC1660 micropower octal DAC for
10‑bit applications. For 8-bit applications, please consult
the LTC1665 micropower octal DAC.
BLOCK DIAGRAM
VOUT A
GND
VCC
VOUT B
8
7
6
5
Differential Nonlinearity (DNL)
LATCH
LATCH
10-BIT
DAC A
LATCH
LATCH
0.75
0.60
10-BIT
DAC B
0.40
LSB
0.20
CONTROL
LOGIC
ADDRESS
DECODER
0
–0.20
–0.40
–0.60
SHIFT REGISTER
–0.75
1
2
3
4
CS/LD
SCK
DIN
0
256
512
CODE
768
1023
REF
1661 G02
1661 BD
1661fa
1
