19-2333; Rev 2; 2/03
2.7V to 3.6V and 4.5V to 5.5V, Low-Power,
4-/12-Channel, 2-Wire Serial, 12-Bit ADCs
General Description
Features
o High-Speed I C-Compatible Serial Interface
400kHz Fast Mode
2
The MAX1236–MAX1239 low-power, 12-bit, multichan-
nel analog-to-digital converters (ADCs) feature internal
track/hold (T/H), voltage reference, clock, and an
1.7MHz High-Speed Mode
2
I C-compatible 2-wire serial interface. These devices
o Single-Supply
operate from a single supply of 2.7V to 3.6V (MAX1237/
MAX1239) or 4.5V to 5.5V (MAX1236/MAX1238) and
require only 670µA at the maximum sampling rate of
94.4ksps. Supply current falls below 230µA for sam-
pling rates under 46ksps. AutoShutdown™ powers
down the devices between conversions, reducing sup-
ply current to less than 1µA at low throughput rates.
The MAX1236/MAX1237 have four analog input chan-
nels each, while the MAX1238/MAX1239 have 12 ana-
log input channels each. The fully differential analog
inputs are software configurable for unipolar or bipolar,
and single-ended or differential operation.
2.7V to 3.6V (MAX1237/MAX1239)
4.5V to 5.5V (MAX1236/MAX1238)
o Internal Reference
2.048V (MAX1237/MAX1239)
4.096V (MAX1236/MAX1238)
o External Reference: 1V to V
o Internal Clock
DD
o 4-Channel Single-Ended or 2-Channel Fully
Differential (MAX1236/MAX1237)
o 12-Channel Single-Ended or 6-Channel Fully
The full-scale analog input range is determined by the
internal reference or by an externally applied reference
voltage ranging from 1V to V . The MAX1237/
DD
Differential (MAX1238/MAX1239)
o Internal FIFO with Channel-Scan Mode
MAX1239 feature a 2.048V internal reference and the
MAX1236/MAX1238 feature a 4.096V internal reference.
o Low Power
670µA at 94.4ksps
230µA at 40ksps
60µA at 10ksps
6µA at 1ksps
0.5µA in Power-Down Mode
The MAX1236/MAX1237 are available in an 8-pin µMAX
package. The MAX1238/MAX1239 are available in a 16-
pin QSOP package. The MAX1236–MAX1239 are guar-
anteed over the extended temperature range
(-40°C to +85°C). For pin-compatible 10-bit parts, refer to
the MAX1136–MAX1139 data sheet. For pin-compatible
8-bit parts, refer to the MAX1036–MAX1039 data sheet.
o Software-Configurable Unipolar/Bipolar
o Small Packages
8-Pin µMAX (MAX1236/MAX1237)
16-Pin QSOP (MAX1238/MAX1239)
Applications
Hand-Held Portable Applications
Medical Instruments
Ordering Information
Battery-Powered Test Equipment
Solar-Powered Remote Systems
Received-Signal-Strength Indicators
System Supervision
TEMP
RANGE
PIN-
PACKAGE ADDRESS (LSB)
I2C SLAVE INL
PART
MAX1236EUA -40°C to +85°C 8 µMAX
MAX1236KEUA* -40°C to +85°C 8 µMAX
MAX1236LEUA* -40°C to +85°C 8 µMAX
MAX1236MEUA* -40°C to +85°C 8 µMAX
MAX1237EUA -40°C to +85°C 8 µMAX
MAX1237KEUA* -40°C to +85°C 8 µMAX
MAX1237LEUA* -40°C to +85°C 8 µMAX
MAX1237MEUA* -40°C to +85°C 8 µMAX
*Future product—contact factory for availability.
0110100
0110000
0110010
0110110
0110100
0110000
0110010
0110110
1
1
1
1
1
1
1
1
Selector Guide
INTERNAL
REFERENCE
(V)
INPUT
CHANNELS
SUPPLY
VOLTAGE (V)
PART
MAX1236EUA
MAX1237EUA
MAX1238EEE
MAX1239EEE
4
4
4.096
2.048
4.096
2.048
4.5 to 5.5
2.7 to 3.6
4.5 to 5.5
2.7 to 3.6
12
12
Ordering Information continued at end of data sheet.
Pin Configurations appear at end of data sheet.
Typical Operating Circuit appears at end of data sheet.
AutoShutdown is a trademark of Maxim Integrated Products, Inc.
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.