Rev 2.0 ©2010 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, CA 94089-1706 Tel: (408) 747-1155 Fax: (408) 747-1286
www.aldinc.com
A
DVANCED
L
INEAR
D
EVICES,
I
NC.
GENERAL DESCRIPTION
The ALD2331A/ALD2331B/ALD2331 is a monolithic high performance
dual precision voltage comparator built with advanced silicon gate EPAD
®
CMOS technology intended for high precision analog applications. The
ALD2331A/ALD2331B/ALD2331 offers ultra-low input offset voltages
and currents at its input pre-amplifier, precision voltage comparator and
high-current output driver integrated on-chip, in one industry standard
pinout 8 Lead PDIP or SOIC package. Primary features include: very high
typical input impedance of 10
12
Ω; low input bias current of 10pA; fast
response time of 750ns with only 10mV input step signal; very low power
dissipation of 55µA per comparator; and single (+5V) or dual (±5V) power
supply operation; and 50mA open drain output drivers.
The input voltage range includes ground, making this comparator ideal for
low level signal detection with high source impedance. The outputs are
open-drain configurations, allowing maximum application flexibility, such as
wired-OR connection and various different output loads. An external pull-
up resistor is required for each output, although the value of the pull-up
resistor can vary over a wide range in order to suit the application needs.
The outputs can be connected to a higher external voltage than V
+.
The ALD2331A/ALD2331B/ALD2331 is ideal for a great variety of precison
analog voltage comparator applications, especially low level signal detec-
tion circuits requiring low standby power, yet retaining high output current
capability as needed.
ALD2331A/ALD2331B/ALD2331
DUAL PRECISION CMOS VOLTAGE COMPARATOR
WITH OPEN DRAIN OUTPUT DRIVER
PIN CONFIGURATION
BLOCK DIAGRAM
(1) OUT
1
(7) OUT
(4) GND
V
+
NONINVERTING INPUT
+IN
1
(3)
INVERTING INPUT
-IN
2
(6)
NONINVERTING INPUT
+IN
2
(5)
INVERTING INPUT
-IN
1
(2)
(8) V
+
APPLICATIONS
• Simple precision reference voltage setting
• High source impedance voltage
comparison circuits
• MOSFET driver
• Dual limit window comparator
• Power supply voltage monitor
• Photo-detector sensor circuit
• Relay or LED driver
• Oscillators
• Battery operated instruments
• Remote signal detection
BENEFITS
• Simple precision reference voltage setting
• On-chip input pre-amplifier and output
buffers
• Precision voltage comparison without
pre-amplifier
• Eliminates need for second power supply
• Wide range of pull-up resistor values
FEATURES
• Fanout of 30LS TTL loads
• Guaranteed to drive 200Ω loads
• Low supply current of 55µA typical
• Pinout of LM193 industry standard voltage comparators
• Extremely low input bias currents -- typically 10pA
• Virtually eliminates source impedance effects
• Low operating supply voltage of 3V to 10V
• Single (+5V) and dual supply (±5V) operation
• High speed for both large and small level signals
-- 300ns typical for TTL inputs
• CMOS, NMOS and TTL compatible
• Wired-OR open drain outputs
• High output sink current -- typically 50mA
• Low supply current spike
1
2
3
4
8
7
6
5
UT
1
-IN
1
+IN
1
GND
V
+
OUT
2
-IN
2
+IN
2
SAL, PAL PACKAGES
Operating Temperature Range *
0°C to +70°C 0°C to +70°C
8-Pin Small 8-PinPlastic
Outline Package (SOIC) Dip Package
ALD2331ASAL ALD2331APAL
ALD2331BSAL ALD2331BPAL
ALD2331SAL ALD2331PAL
ORDERING INFORMATION (“L” suffix for lead free version)
* Contact factory for leaded (non-RoHS) or high temperature versions.