A
DVANCED
L
INEAR
D
EVICES,
I
NC.
ALD2321A/ALD2321B
ALD2321
ULTRA LOW VOS EPAD
®
DUAL CMOS ANALOG VOLTAGE COMPARATOR
GENERAL DESCRIPTION
The ALD2321A/ ALD2321B/ ALD2321 is a monolithic Precision Dual
Voltage Comparator, each having integrated dual complementary
output drivers. It is constructed using advanced silicon gate CMOS
technology. Key features of the ALD2321A/ ALD2321B/ ALD2321
include very high input impedance, very low offset voltage utilizing on-
chip e-trim (EPAD
®
electronic-trimming) technology, flexible multiple
output configurations and fast response time with small overdrive
voltage. It is designed for ultra low level signal detection from high
impedance sources. For many applications the ALD2321A/ ALD2321B/
ALD2321 can eliminate an input amplification stage, a precision input
bias stage, a signal level shift stage and an output buffer stage, and do
the entire job from low level input signal detection to high output driver
---- all on a single chip.
The input voltage includes ground, making this voltage comparator ideal
for single supply +5V or dual supply +/- 5V powered systems. For dual
supply applications, GND pin is connected to the most negative supply
instead of Ground (0.0V). The negative supply voltage can be at any
value between 0.0V and -5V. Each voltage comparator is individually
trimmed at the factory for minimum offset voltage at ground voltage
potential, making the ALD2321A/ ALD2321B/ ALD2321 at its best offset
voltage and ready to compare very low signal level voltages at or near
ground potential. Typically a signal less than 1 mV can be resolved and
detected reliably without requiring amplification. Sensor or detector
signals with signal power as low as 0.004 pW(4 x 10
-15
Watt) can be
readily detected.
Each voltage comparator has two complementary output pins, one for
Source Output (OUT
H
)and the other for Sink Output (OUT). This dual
complementary output allows maximum circuit design flexibility. The
outputs can be used as Single-Ended Driver, Multiple WIRED-OR
Outputs, Push-Pull Outputs or Complementary Outputs. The Sink
Output can be used as an open drain output, which has current sink
capability of up to 50 mA. It can also be connected to an external voltage
higher or lower than V+, which provide level shift of the output swing
levels from other than V+ to GND.
ORDERING INFORMATION
Operating Temperature Range*
0°C to +70°C
16-pin
Small Outline Package
(SOIC)
ALD2321ASC
ALD2321BSC
ALD2321SC
0°C to +70°C
16-Pin
Plastic DIP Package
(PDIP)
ALD2321APC
ALD2321BPC
ALD2321PC
-55°C to +125°C
16-Pin
Ceramic DIP Package
(CDIP)
ALD2321ADC
ALD2321BDC
ALD2321DC
PRODUCT FEATURES
* Ultra low signal power of 4 fW detectable
* Ultra low offset voltage of max. 0.2 mV
* Ultra low input bias currents of typ. 0.01pA
* Low supply current of 110
µA
typical
* Virtually eliminates source impedance effects
* Low operating supply voltage of 3V to 10V
* Single +5V and dual supply
±5V
operation
* High speed for both small and large level
signals 300ns typical for TTL inputs
* CMOS, NMOS and TTL compatible
* Each comparator has separate push and pull
outputs
* High output sink current - typically 50mA
* Low supply current spikes
* Fanout of 30 TTL loads
APPLICATIONS
* Low level signal detector
* Dual limit window comparator
* Power supply voltage monitor
* Photo-detector sensor circuit
* Relay or LED driver
* Oscillators
* Battery operated instruments
* Remote signal detection
PIN CONFIGURATION
OUT
1
OUT
1H
-IN
1
+IN
1
GND
VE
11
VE
12
N/C
*
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
V
+
OUT
2
OUT
2H
-IN
2
+IN
2
VE
21
VE
22
N/C
*
DC, PC, SC PACKAGE
*
*N/C pins are connected internally. Do not connect externally.
* Contact factory for industrial temperature range
© 2004 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, California 94089 -1706 Tel: (408) 747-1155 Fax: (408) 747-1286 http://www.aldinc.com
ALD [ ADVANCED LINEAR DEVICES ]
