DAC121C081_08 Datasheet, PDF (1/24 Pages) National Semiconductor (TI) – 12-Bit Micro Power Digital-to-Analog Converter with an I2C-Compatible Interface

March 13, 2008
DAC121C081/ DAC121C085
12-Bit Micro Power Digital-to-Analog Converter with an
I²C-Compatible Interface
General Description
The DAC121C081 is a 12-bit, single channel, voltage-output
digital-to-analog converter (DAC) that operates from a +2.7V
to 5.5V supply. The output amplifier allows rail-to-rail output
swing and has an 8.5µsec settling time. The DAC121C081
uses the supply voltage as the reference to provide the widest
dynamic output range and typically consumes 132µA while
operating at 5.0V. It is available in 6-lead TSOT and LLP
packages and provides three address options (pin se-
lectable).
As an alternative, the DAC121C085 provides nine I²C ad-
dressing options and uses an external reference. It has the
same performance and settling time as the DAC121C081. It
is available in an 8-lead MSOP.
The DAC121C081 and DAC121C085 use a 2-wire, I²C-com-
patible serial interface that operates in all three speed modes,
including high speed mode (3.4MHz). An external address
selection pin allows up to three DAC121C081 or nine
DAC121C085 devices per 2-wire bus. Pin compatible alter-
natives to the DAC121C081 are available that provide addi-
tional address options.
The DAC121C081 and DAC121C085 each have a 16-bit reg-
ister that controls the mode of operation, the power-down
condition, and the output voltage. A power-on reset circuit
ensures that the DAC output powers up to zero volts. A power-
down feature reduces power consumption to less than a
microWatt. Their low power consumption and small packages
make these DACs an excellent choice for use in battery op-
erated equipment. Each DAC operates over the extended
industrial temperature range of −40°C to +125°C.
The DAC121C081 and DAC121C085 are each part of a fam-
ily of pin compatible DACs that also provide 8 and 10 bit
resolution. For 8-bit DACs see the DAC081C081 and
DAC081C085. For 10-bit DACs see the DAC101C081 and
DAC101C085.
Features
■ ^{Guaranteed Monotonicity to 12-bits}
■ ^{Low Power Operation: 156 µA max @ 3.3V}
■ ^{Extended power supply range (+2.7V to +5.5V)}
■ ^{I2C-Compatible 2-wire Interface which supports standard}
(100kHz), fast (400kHz), and high speed (3.4MHz) modes
■ ^{Rail-to-Rail Voltage Output}
■ ^{Very Small Package}
Key Specifications
■ ^Resolution
■ ^INL
■ ^DNL
■ ^{Settling Time}
■ ^{Zero Code Error}
■ ^{Full-Scale Error}
■ ^{Supply Power}
— Normal
— Power Down
12 bits
±8 LSB (max)
+0.6 / -0.5 LSB (max)
8.5 µs (max)
+10 mV (max)
−0.7 %FS (max)
380 µW (3V) / 730 µW (5V) typ
0.5 µW (3V) / 0.9 µW (5V) typ
Applications
■ ^{Industrial Process Control}
■ ^{Portable Instruments}
■ ^{Digital Gain and Offset Adjustment}
■ ^{Programmable Voltage & Current Sources}
■ ^{Test Equipment}
Pin-Compatible Alternatives
All devices are fully pin and function compatible.
Resolution TSOT-6 and LLP-6 MSOP-8 Package w/
Packages
External Reference
12-bit
DAC121C081
DAC121C085
10-bit
DAC101C081
DAC101C085
8-bit
DAC081C081
DAC081C085
Connection Diagrams
30004901
I2C® is a registered trademark of Phillips Corporation.
© 2008 National Semiconductor Corporation
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