ADS7924_14 Datasheet, PDF (1/45 Pages) Texas Instruments – 2.2V, 12-Bit, 4-Channel, microPOWER™ ANALOG-TO-DIGITAL CONVERTER WITH I2C INTERFACE

ADS7924
www.ti.com
SBAS482A – JANUARY 2010 – REVISED MAY 2010
2.2V, 12-Bit, 4-Channel, microPOWER™
ANALOG-TO-DIGITAL CONVERTER WITH I²C INTERFACE
Check for Samples: ADS7924
FEATURES
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•234 Intelligent Monitoring:
– Auto-Sequencing of 4-Channel Multiplexer
– Individual Alarm Thresholds for Each
Channel
– Programmable Scan Rate
• Micropower Monitoring:
– Four-Channel Scanning:
– Every 1ms → 25mW
– Every 10ms → 5mW
– < 1µA of Power-Down Current
– Programmable Interrupt Pin Controls
Shutdown/Wakeup of the Microcontroller
– Auto Power-Down Control
– PWRCON Pin Allows Shutdown of External
Op Amp
• Wide Supply Range:
– Analog Supply: 2.2V to 5.5V
– Digital Supply: 1.65V to 5.5V
• Small Footprint: 3mm × 3mm QFN
APPLICATIONS
• Portable and Battery-Powered Systems:
– Medical, Communications, Remote Sensor
Signal Monitoring, Power-Supply
Monitoring
• Energy Harvesting
MUX OUT ADCIN
AVDD
DESCRIPTION
The ADS7924 is a four-channel, 12-bit,
analog-to-digital converter (ADC) with an I²C™
interface. With its low-power ADC core, support for
low-supply operation, and a flexible measurement
sequencer that essentially eliminates power
consumption between conversions, the ADS7924
forms a complete monitoring system for power-critical
applications such as battery-powered equipment and
energy harvesting systems.
The ADS7924 features dedicated data registers and
onboard programmable digital threshold comparators
for each input. Alarm conditions can be programmed
that generate an interrupt. The combination of data
buffering, programmable threshold comparisons, and
alarm interrupts minimize the host microcontroller
time needed to supervise the ADS7924.
The four-channel input multiplexer (MUX) is routed
through external pins to allow a common signal
conditioning circuit to be used between the MUX and
ADC, thereby reducing overall component count. The
low-power ADC uses the analog supply as its
reference and can acquire and convert signals in only
10ms. An onboard oscillator eliminates the need to
supply a master clock.
The ADS7924 is offered in a small 3mm × 3mm QFN
and is fully specified for operation over the industrial
temperature range of –40°C to +85°C.
DVDD
CH0
CH1
CH2
CH3
4-Channel
MUX
SAR
ADC
Oscillator
Data Buffers,
Sequencer, and
Alarms
I²C
Interface
SDA
SCL
A0
INT
PWRCON
RESET
AGND
DGND
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Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
microPOWER is a trademark of Texas Instruments Incorporated.
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I²C is a trademark of NXP Semiconductors.
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All other trademarks are the property of their respective owners.
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PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2010, Texas Instruments Incorporated