March 2000
ADC12130/ADC12132/ADC12138
Self-Calibrating 12-Bit Plus Sign Serial I/O A/D
Converters with MUX and Sample/Hold
General Description
Features
n Serial I/O (MICROWIRE, SPI and QSPI Compatible)
n 2 or 8 channel differential or single-ended multiplexer
n Analog input sample/hold function
n Power down mode
The ADC12130, ADC12132 and ADC12138 are 12-bit plus
sign successive approximation A/D converters with serial I/O
and configurable input multiplexer. The ADC12132 and
ADC12138 have a 2 and an 8 channel multiplexer, respec-
tively. The differential multiplexer outputs and A/D inputs are
available on the MUXOUT1, MUXOUT2, A/DIN1 and A/DIN2
pins. The ADC12130 has a two channel multiplexer with the
multiplexer outputs and A/D inputs internally connected. The
ADC12130 family is tested with a 5 MHz clock. On request,
these A/Ds go through a self calibration process that adjusts
n Programmable acquisition time
n Variable digital output word length and format
n No zero or full scale adjustment required
n 0V to 5V analog input range with single 5V power
supply
±
linearity, zero and full-scale errors to typically less than
LSB each.
1
Key Specifications
The analog inputs can be configured to operate in various
combinations of single-ended, differential, or
n Resolution: 12-bit plus sign
n 12-bit plus sign conversion time: 8.8 µs (max)
n 12-bit plus sign throughput time: 14 µs (max)
pseudo-differential modes. A fully differential unipolar analog
input range (0V to +5V) can be accommodated with a single
+5V supply. In the differential modes, valid outputs are ob-
tained even when the negative inputs are greater than the
positive because of the 12-bit plus sign output data format.
±
n Integral linearity error:
2 LSB (max)
±
n Single supply: 3.3V or 5V 10%
n Power consumption
— 3.3V
15 mW (max)
40 µW (typ)
33 mW (max)
100 µW (typ)
The serial I/O is configured to comply with the NSC MI-
— 3.3V power down
— 5V
— 5V power down
™
CROWIRE . For voltage references, see the LM4040 or
LM4041.
Applications
n Pen-based computers
n Digitizers
n Global positioning systems
ADC12138 Simplified Block Diagram
DS012079-1
TRI-STATE® is a registered trademark of National Semiconductor Corporation.
™
™
™
COPS microcontrollers, HPC and MICROWIRE are trademarks of National Semiconductor Corporation.
© 2000 National Semiconductor Corporation
DS012079
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