MAX1280 Datasheet, PDF (1/24 Pages) Maxim Integrated Products – 400ksps/300ksps, Single-Supply, Low-Power, 8-Channel, Serial 12-Bit ADCs with Internal Reference

19-1684; Rev 0; 5/00
400ksps/300ksps, Single-Supply, Low-Power, 8-Channel,
Serial 12-Bit ADCs with Internal Reference
General Description
The MAX1280/MAX1281 12-bit ADCs combine an 8-chan-
nel analog-input multiplexer, high-bandwidth track/hold,
and serial interface with high conversion speed and low
power consumption. The MAX1280 operates from a single
+4.5V to +5.5V supply; the MAX1281 operates from a sin-
gle +2.7V to +3.6V supply. Both devices’ analog inputs
are software configurable for unipolar/bipolar and single-
ended/pseudo-differential operation.
The 4-wire serial interface connects directly to
SPI™/QSPI™/MICROWIRE™ devices without external
logic. A serial strobe output allows direct connection to
TMS320-family digital signal processors. The MAX1280/
MAX1281 use an external serial-interface clock to per-
form successive-approximation analog-to-digital con-
versions. Both parts feature an internal +2.5V reference
and a reference-buffer amplifier with a ±1.5% voltage-
adjustment range. An external reference with a 1V to
V_DD1 range may also be used.
The MAX1280/MAX1281 provide a hard-wired SHDN
pin and four software-selectable power modes (normal
operation, reduced power, fast power-down, and full
power-down). These devices can be programmed to
automatically shut down at the end of a conversion or to
operate with reduced power. When using the power-
down modes, accessing the serial interface automatical-
ly powers up the devices, and the quick turn-on time
allows them to be powered down between all conver-
sions. This technique can cut supply current to under
100µA at reduced sampling rates.
The MAX1280/MAX1281 are available in 20-pin TSSOP
packages. These devices are higher-speed versions of
the MAX146/MAX147 (for more information, see the
respective data sheet).
Applications
Portable Data Logging
Data Acquisition
Medical Instruments
Battery-Powered Instruments
Pen Digitizers
Process Control
SPI and QSPI are trademarks of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
Features
o 8-Channel Single-Ended or 4-Channel
Pseudo-Differential Inputs
o Internal Multiplexer and Track/Hold
o Single-Supply Operation
+4.5V to +5.5V (MAX1280)
+2.7V to +3.6V (MAX1281)
o Internal +2.5V Reference
o 400ksps Sampling Rate (MAX1280)
o Low Power 2.5mA (400ksps)
1.3mA (Reduced-Power Mode)
0.9mA (Fast Power-Down Mode)
2µA (Full Power-Down)
o SPI/QSPI/MICROWIRE/TMS320-Compatible
4-Wire Serial Interface
o Software-Configurable Unipolar or Bipolar Inputs
o 20-Pin TSSOP Package
Ordering Information
PART
TEMP.
RANGE
PIN-
PACKAGE
INL
(LSB)
MAX1280BCUP 0°C to +70°C 20 TSSOP
±1
MAX1280BEUP -40°C to +85°C 20 TSSOP
±1
Ordering Information continued at end of data sheet.
Pin Configuration
TOP VIEW
CH0 1
CH1 2
CH2 3
CH3 4
CH4 5
CH5 6
CH6 7
CH7 8
COM 9
SHDN 10
MAX1280
MAX1281
TSSOP
20 VDD1
19 V_DD2
18 SCLK
17 CS
16 DIN
15 SSTRB
14 DOUT
13 GND
12 REFADJ
11 REF
________________________________________________________________ Maxim Integrated Products 1
For free samples and the latest literature, visit www.maxim-ic.com or phone [phone].
For small orders, phone [phone].