ADC128D818 Datasheet, PDF (1/38 Pages) National Semiconductor (TI) – 12-Bit, 8-Channel, ADC System Monitor with Temperature Sensor, Internal/External Reference, and I2C Interface

ADC128D818
April 1, 2010
12-Bit, 8-Channel, ADC System Monitor with Temperature
Sensor, Internal/External Reference, and I²C Interface
1.0 General Description
The ADC128D818 I²C™ system monitor is designed for max-
imum flexibility. The system monitor can be configured for
single-ended and/or pseudo-differential inputs. An on-board
temperature sensor, combined with WATCHDOG window
comparators, and an interrupt output pin, INT, allow easy
monitoring and out-of-range alarms for every channel. A high
performance internal reference is also available to provide for
a complete solution in the most difficult operating conditions.
The ADC128D818’s 12-bit delta-sigma ADC supports Stan-
dard Mode (Sm, 100 kbits/s) and Fast Mode (Fm, 400kbits/s)
I²C interfaces. The ADC128D818 includes a sequencer to
control channel conversions and stores all converted results
in independent registers for easy microprocessor retrieval.
Unused channels can be shut down independently to con-
serve power.
The ADC can use either an internal 2.56V reference or a vari-
able external reference. An analog filter is included on the
I²C digital control lines to provide improved noise immunity.
The device also includes a TIMEOUT reset function on SDA
and SCL to prevent I²C bus lock-up.
The ADC128D818 operates from +3.0 to +5.5V power supply
voltage range, –40°C to 125°C temperature range, and the
device is available in a 16-pin TSSOP package.
2.0 Applications
■ ^{Communications Infrastructure}
■ ^{Thermal / Hardware Server Monitors}
■ ^{System Monitors}
■ ^{Industrial and Medical Systems}
■ ^{Electronic Test Equipment and Instrumentation}
■ ^{Power Supply Monitoring / Supervision}
3.0 Features
■ ^{12-bit Resolution Delta-Sigma ADC}
■ ^{Local Temperature Sensing}
■ ^{Configurable Single-Ended and/or Pseudo-Diff. Inputs}
■ ^{+2.56V Internal VREF or Variable External VREF}
■ ^{WATCHDOG Window Comparators with Status and Mask}
Registers of All Measured Values
■ ^{Independent Registers for Storing Measured Values}
■ ^{INT Output Notifies Microprocessor of Error Event}
■ ^{I2C Serial Bus Interface Compatibility}
■ ^{9 Selectable Addresses}
■ ^{TIMEOUT Reset Function to Prevent I2C Bus Lock-Up}
■ ^{Individual Channel Shutdown to Limit Power Consumption}
■ ^{Deep Shutdown Mode to Minimize Power Consumption}
■ ^{TSSOP 16-Lead Package}
4.0 Key Specifications
■ ADC Resolution
■ Supply Voltage Range
■ Total Unadjusted Error
■ Integral Non-Linearity
■ Differential Non-Linearity
■ Operating Current
■ Deep Shutdown Current
■ Temperature Resolution
■ Temp. Accuracy (–40°C to 125°C)
■ Temp. Accuracy (–25°C to 100°C)
12-bit
+3.0V to +5.5V
–0.45/+0.2%
±1LSb
±1LSb
0.56 mA
10 µA
0.5°C/LSb
± 3°C
± 2°C
5.0 Typical Application
I²C® is a registered trademark of the Philips Corporation.
© 2010 National Semiconductor Corporation 300963
30096301
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