12-bit SAR ADC
8 single-ended analog input channels
Analog input range: 0 V to 2.5 V
12-bit temperature to digital converter
Temperature sensor accuracy of ±1°C typical
Channel sequencer operation
Specified for VDD of 2.8 V to 3.6 V
Logic voltage VDRIVE = 1.65 V to 3.6 V
Internal 2.5 V reference
I2C-compatible serial interface supports standard and
fast speed modes
Out of range indicator/alert function
Power-down current: 13 µA maximum
20-lead LFCSP package
ENHANCED PRODUCT FEATURES
Supports defense and aerospace applications (AQEC
Extended industrial temperature range: −55°C to +125°C
Controlled manufacturing baseline
1 assembly/test site
1 fabrication site
Product change notification
Qualification data available upon request
The AD7291-EP is a 12-bit, low power, 8-channel, successive
approximation analog-to-digital converter (ADC) with an
internal temperature sensor.
The device operates from a single 3.3 V power supply and
features an I2C-compatible interface. The device contains a
9-channel multiplexer and a track-and-hold amplifier with an
input bandwidth of 30 MHz. The device has an on-chip 2.5 V
reference that can be disabled to allow the use of an external
The AD7291-EP provides a 2-wire serial interface compatible
with I2C interfaces. The I2C interface supports standard and fast
I2C interface modes. The AD7291-EP normally remains in a
partial power-down state while not converting and powers up
for conversions. The conversion process can be controlled by a
command mode where conversions occur across I2C write
operations or an autocycle mode selected through software control.
8-Channel, I2C, 12-Bit SAR ADC
with Temperature Sensor
FUNCTIONAL BLOCK DIAGRAM
The AD7291-EP includes a high accuracy band gap temperature
sensor, which is monitored and digitized by the 12-bit ADC to
give a resolution of 0.25°C.
The AD7291-EP offers a programmable sequencer, which
enables the selection of a preprogrammable sequence of
channels for conversion.
On-chip limit registers can be programmed with high and low
limits for the conversion results; an out-of-range indicator output
(ALERT) becomes active when the programmed high or low
limits are violated by the conversion result. This output can be
used as an interrupt.
Additional application and technical information can be found
in the AD7291 data sheet.
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responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
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