MAX1284-MAX1285 Datasheet, PDF (1/15 Pages) Maxim Integrated Products – 400ksps/300ksps, Single-Supply, Low-Power, Serial 12-Bit ADCs with Internal Reference

19-1687; Rev 1; 7/00
400ksps/300ksps, Single-Supply, Low-Power,
Serial 12-Bit ADCs with Internal Reference
General Description
The MAX1284/MAX1285 12-bit analog-to-digital con-
verters (ADCs) combine a high-bandwidth track/hold
(T/H), a serial interface with high conversion speed, an
internal +2.5V reference, and low power consumption.
The MAX1284 operates from a single +4.5V to +5.5V
supply. The MAX1285 operates from a single +2.7V to
+3.6V supply.
The 3-wire serial interface connects directly to
SPI™/QSPI™/ MICROWIRE™ devices without external
logic. The devices use an external serial-interface clock
to perform successive-approximation analog-to-digital
conversions.
Low power, ease of use, and small package size make
these converters ideal for remote-sensor and data-acqui-
sition applications or for other circuits with demanding
power consumption and space requirements. The
MAX1284/MAX1285 are available in 8-pin SO packages.
These devices are pin-compatible, higher-speed ver-
sions of the MAX1240/MAX1241. Refer to the respec-
tive data sheets for more information.
Applications
Portable Data Logging
Data Acquisition
Medical Instruments
Battery-Powered Instruments
Pen Digitizers
Process Control
____________________________Features
o Single-Supply Operation
+4.5V to +5.5V (MAX1284)
+2.7V to +3.6V (MAX1285)
o ±1LSB (max) DNL, ±1LSB (max) INL
o 400ksps Sampling Rate (MAX1284)
o Internal Track/Hold
o +2.5V Internal Reference
o Low Power: 2.5mA (400ksps)
o SPI/QSPI/MICROWIRE 3-Wire Serial-Interface
o Pin-Compatible, High-Speed Upgrades to
MAX1240/MAX1241
o 8-Pin SO Package
Ordering Information
PART
TEMP.
RANGE
PIN-
SUPPLY
PACKAGE VOLTAGE (V)
MAX1284BCSA 0°C to +70°C 8 SO
5
MAX1284BESA* -40°C to +85°C 8 SO
5
MAX1285BCSA 0°C to +70°C 8 SO
2.7 to 3.6
MAX1285BESA -40°C to +85°C 8 SO
2.7 to 3.6
*Future product—contact factory for availability.
Pin Configuration
TOP VIEW
V_{DD 1}
AIN 2
SHDN 3
REF 4
MAX1284
MAX1285
SO
8 SCLK
7 CS
6 DOUT
5 GND
CS ⁷
SCLK ⁸
SHDN ³
AIN ²
Functional Diagram
V_DD
1
CONTROL
LOGIC
T/H
INT
CLOCK
12-BIT
SAR
OUTPUT
SHIFT
REGISTER
6
DOUT
SPI and QSPI are trademarks of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
4
REF
+2.5V REFERENCE
5
GND
MAX1284
MAX1285
________________________________________________________________ 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.