Features: • Complete 32-Channel 12-Bit A/D Converter with Sample & Hold, Reference, Clock and 3-State Outputs
• Fast Conversion, less than 15mS
• Microprocessor Bus Interface
• Parallel or Serial Data Output Modes
• 65 ns Bus Access Time
• Remote Analog Ground Sensing
• Overvoltage Protected Input (50 V over the Supply Voltages)
• Precision Reference for Long Term Stability and Low Gain T.C.
• Guaranteed Linearity Over Temperature
• Guaranteed Performance at +12/5 V, ±12 & ±15 V
• Low Power (3 mW per Channel Typical)
• 16 Channel Version: MP3276 & MP3275Pinout
SpecificationsVCC to DGND . . . . . . . . . . . . . . . . . . . . . . .0 to+16.5 V
VEE to DGND . . . . . . . . . . . . . . . . . . . . .. . .0 to16.5 V
VDD to DGND . . . . . . . . . . . . . . . . . . . . . . . . . .0 to+7 V
AGND to DGND. . . . . . . . . . . . . . . . . . . . . . . . . . . . ±1 V
Digital Inputs/Outputs
to DGND . . . . . . . . . . . . . . . . .0.5 V to VLOGIC +0.5 V
Analog Inputs (AIN0 AIN31, GND REF)
to AGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .±60 V
REF OUT Indefinite . . . . . . . . . . . . . . . . .short to DGND
Momentary short to VCC
Maximum Junction Temperature . . . . . . . . . . . . .150°C
Package Power Dissipation Rating to 75°C
PGA, PLCC . . . . . . . . . . . . . . . . . . . . . . . . . . . .1800 mW
Derates above 75°C . . . . . . . . . . . . . . . . ..25 mW/°C
Lead Temperature, Soldering . . . . . . . ..300°C, 10 Sec
Storage Temperature (Ceramic) . . .65°C to +150°C
NOTES:
1 Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation at or above this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability.
2 Any input pin which can see a value outside the absolute maximum ratings should be protected by Schottky diode clamps (HP5082-2835) from input pin to the supplies. All logic inputs have protection diodes which will protect the device from short transients outside the supplies of less than 100mA for less than 100ms.
DescriptionThe MP3274 is a complete 32-channel, 12-bit Data Acquisition Subsystem with 3-state output buffers for direct interfacing to 16-bit microprocessor buses. Implemented using an advanced BiCMOS process, the MP3274 combines a 32-channel passive overvoltage protected multiplexer instrumentation amp, a sample & hold, a SAR, a 12-bit decoded D/A, a comparator, a precision reference and the control logic to achieve an accurate, repeated conversion in less than 15ms, and a mux/instrumentation amp settling period of less than 10ms.
A unique input of MP3274 design provides input overvoltage protection to 50 V over the supply voltages. Therefore, an overvoltage condition can exist on unselected channels without disrupting the measured channel or operation of the MP3274! The internal 4 V reference has sufficient output current to provide other system reference needs. Precision thin film scaling and offset resistors are laser trimmed to provide for less than 2 LSB INL for +10 V inputs on all channels.
In addition, the MP3274 will output either full scale (0111 ....) for overrange and full scale (1000....) for underrange conditions. This greatly simplifies microprocessor software development.
MP3274 Data Sheet
