19-1685; Rev 0; 5/00
300ksps/400ksps, Single-Supply, Low-Power,
8-Channel, Serial 10-Bit ADCs with Internal Reference
General Description
The MAX1080/MAX1081 10-bit analog-to-digital convert-
ers (ADCs) combine an 8-channel analog-input multiplex-
er, high-bandwidth track/hold (T/H), and serial interface
with high conversion speed and low power consumption.
The MAX1080 operates from a single +4.5V to +5.5V sup-
ply; the MAX1081 operates from a single +2.7V to +3.6V
supply. Both devices’ analog inputs are software config-
urable for unipolar/bipolar and single-ended/pseudo-dif-
ferential operation.
The 4-wire serial interface connects directly to
SPI™/QSPI™ and MICROWIRE™ devices without external
logic. A serial strobe output allows direct connection to
TMS320-family digital signal processors. The MAX1080/
MAX1081 use an external serial-interface clock to perform
successive-approximation analog-to-digital conversions.
The devices feature an internal +2.5V reference and a ref-
erence-buffer amplifier with a ±1.5% voltage-adjustment
range. An external reference with a 1V to V
DD1
range may
also be used.
The MAX1080/MAX1081 provide a hard-wired
SHDN
pin
and four software-selectable power modes (normal opera-
tion, reduced power (REDP), fast power-down (FASTPD),
and full power-down (FULLPD)). 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
automatically powers up the devices, and the quick turn-
on time allows them to be shut down between all conver-
sions. This technique can cut supply current below 100mA
at lower sampling rates.
The MAX1080/MAX1081 are available in a 20-pin TSSOP
package. These devices are higher-speed versions of the
MAX148/MAX149. For more information, refer to the
respective data sheet.
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 (MAX1080)
+2.7V to +3.6V (MAX1081)
o
Internal +2.5V Reference
o
400ksps Sampling Rate (MAX1080)
o
Low Power: 2.5mA (400ksps)
1.3mA (REDP)
0.9mA (FASTPD)
2µA (FULLPD)
o
SPI/QSPI/MICROWIRE/TMS320-Compatible 4-Wire
Serial Interface
o
Software-Configurable Unipolar or Bipolar Inputs
o
20-Pin TSSOP Package
MAX1080/MAX1081
Ordering Information
PART
MAX1080ACUP
MAX1080BCUP
MAX1080AEUP
TEMP.
RANGE
0°C to +70°C
0°C to +70°C
-40°C to +85°C
PIN-
PACKAGE
20 TSSOP
20 TSSOP
20 TSSOP
INL
(LSB)
±1/2
±1
±1/2
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
20 V
DD1
19 V
DD2
18 SCLK
Applications
Portable Data Logging
Data Acquisition
Medical Instruments
Battery-Powered Instruments
Pen Digitizers
Process Control
MAX1080
MAX1081
17
CS
16 DIN
15 SSTRB
14 DOUT
13 GND
12 REFADJ
11 REF
Typical Operating Circuit appears at end of data sheet.
SPI and QSPI are trademarks of Motorola, Inc.
MICROWIRE is a trademark of National Semiconductor Corp.
COM 9
SHDN 10
TSSOP
________________________________________________________________
Maxim Integrated Products
1
For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
