EVALUATION KIT AVAILABLE
MAX187/MAX189
+5V, Low-Power, 12-Bit Serial ADCs
General Description
Features
The MAX187/MAX189 serial 12-bit analog-to-digital converters (ADCs) operate from a single +5V supply and
accept a 0 to 5V analog input. Both parts feature an 8.5Fs
successive-approximation ADC, a fast track/hold (1.5Fs),
an on-chip clock, and a high-speed 3-wire serial interface.
S 12-Bit Resolution
The MAX187/MAX189 digitize signals at a 75ksps
throughput rate. An external clock accesses data from
the interface, which communicates without external
hardware to most digital signal processors and microcontrollers. The interface is compatible with SPI, QSPIK,
and MICROWIREM.
S Low Power: 2µA Shutdown Current
1.5mA Operating Current
The MAX187 has an on-chip buffered reference, and
the MAX189 requires an external reference. Both the
MAX187 and MAX189 save space with 8-pin PDIP and
16-pin SO packages. Power consumption is 7.5mW and
reduces to only 10FW in shutdown.
Excellent AC characteristics and very low power consumption combined with ease of use and small package
size make these converters ideal for remote DSP and
sensor applications, or for circuits where power consumption and space are crucial.
S ±½ LSB Integral Nonlinearity (MAX187A/MAX189A)
S Internal Track/Hold, 75kHz Sampling Rate
S Single +5V Operation
S Internal 4.096V Buffered Reference (MAX187)
S 3-Wire Serial Interface, Compatible with SPI, QSPI,
and MICROWIRE
S Small-Footprint 8-Pin PDIP and 16-Pin SO
Applications
Portable Data Logging
Remote Digital Signal Processing
Isolated Data Acquisition
High-Accuracy Process Control
Ordering Information appears at end of data sheet.
For related parts and recommended products to use with this part,
refer to www.maximintegrated.com/MAX187.related.
Functional Diagram
GND 5
REF10kI
+2.5V
DAC
AV = 1.638
(4.096V)
6 DOUT
8 SCLK
REF+
BANDGAP
REFERENCE
12-BIT
SAR
(MAX187 ONLY)
REF 4
AIN 2
OUTPUT
SHIFT
REGISTER
T/H
MAX187
MAX189
COMPARATOR
BUFFER ENABLE/DISABLE
VDD 1
CONTROL
AND
TIMING
7 CS
3 SHDN
NOTE: PIN NUMBERS SHOWN ARE FOR 8-PIN DIPs ONLY
QSPI is a trademark of Motorola.
MICROWIRE is a registered trademark of National Semiconductor Corp.
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
19-0196; Rev 1; 3/12
