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
ADVANCED
LINEAR
DEVICES, INC.
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 1012Ω; 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
2
(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
O
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.
ALD2331A/ALD2331B/ALD2331 Advanced Linear Devices 2 of 8
ABSOLUTE MAXIMUM RATINGS
Supply voltage, V+ +10.6V
Differential input voltage range -0.3V to V+ +0.3V
Power dissipation 600 mW
Operating temperature range SAL, PAL packages 0°C to +70°C
Storage temperature range -65°C to +150°C
Lead temperature, 10 seconds +260°C
OPERATING ELECTRICAL CHARACTERISTICS
TA = 25°C V+ = +5V unless otherwise specified
Supply VS ±1.5 ±5 ±1.5 ±5 ±1.5 ±5 V Dual Supply
Voltage V+ 3 10 3 10 3 10 V Single Supply
Supply IS 110 180 110 180 110 180 µA No Load
Current Two Comparators
Voltage Gain AVD 50 150 50 150 50 150 V/mV RLOAD ≥ 15K
Input Offset Voltage VOS 0.2 0.5 0.5 1.0 1.0 2.0 mV RLOAD ≥ 1.5KΩ
Input Offset Current1IOS 0.01 20 0.01 20 0.01 20 pA
Input Bias Current1 IB 0.01 20 0.01 20 0.01 20 pA
Common Mode Input VICR -0.3 V+-1.5 -0.3 V+-1.5 -0.3 V+-1.5 V
Voltage Range2
Low Level Sink VOL 0.15 0.4 0.15 0.4 0.15 0.4 V ISINK = 12mA
Output Voltage VINPUT = 1V Differential
Low Level Sink IOL 24 50 24 50 24 50 mA VOL = 1.0 V
Output Current SINK OUTPUT ON
High Level Sink Output IL 0.01 20 0.01 20 0.01 20 nA VOUT = 5.0 V
Leakage Current SINK OUTPUT OFF
Response Time2tRP 1.1 1.1 1.1 µs RL = 5.1KΩ, CL = 15pF
5mV Input Step/
5mV Overdrive
tRP 2.4 2.4 2.4 µs RL = 5.1KΩ ,CL =15pF
1mVInput Step/
1mV Overdrive
tRP 600 600 600 ns RL = 5.1KΩ, CL = 15pF
100mV Input Step/
5mV Overdrive
tRP 300 300 300 ns RL = 5.1KΩ ,CL =15pF
TTL level Input Step
Common Mode CMRR 80 80 80 dB VINPUT = 0V to 2.5V
Rejection Ratio
Power Supply PSRR 75 75 75 dB V+ = 4V to 5V
Rejection Ratio
2331A 2331B 2331
Parameter Symbol Min Typ Max Min Typ Max Min Typ Max Unit Test Conditions
Notes: 1 Consists of junction leakage currents
2 Sample test parameter
ALD2331A/ALD2331B/ALD2331 Advanced Linear Devices 3 of 8
SUPPLY CURRENT vs. SUPPLY VOLTAGE
012
200
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (µA)
0
108624
20
40
60
80
100
120
140
160
180 No Load
Two Comparators
TA = 25
0
C
TA = 125
0
C
TA = -55
0
C
-55 -25 0 25 50 75 100 125
0
1
10
100
1000
V
+
= +5V
INPUT BIAS CURRENT vs. TEMPERATURE
AMBIENT TEMPERATURE (
0
C)
INPUT BIAS CURRENT (pA)
LOW LEVEL OUTPUT VOLTAGE 
vs. TEMPERATURE
0.5
0.4
0.3
0.2
0.1
0.0
LOW LEVEL OUTPUT VOLTAGE (V)
AMBIENT TEMPERATURE (°C)
-55 -25 025 50 125
100
75
V
+
= +3.5V
V
+
= +5V
V
+
= +10V
I
SINK = 12mA
V
INPUT =
1V 
Differential
SUPPLY CURRENT vs.TEMPERATURE
SUPPLY CURRENT (µA)
AMBIENT TEMPERATURE (°C)
-55 -25 025 50 12510075
160
140
120
100
60
80
180
200
V+ = +5V
No Load
Two Comparators
TYPICAL PERFORMANCE CHARACTERISTICS
COMMON - MODE VOLTAGE REFERRED
TO SUPPLY VOLTAGE
TEMPERATURE (°C)
0.5
V+
-0.5
-1.0
0.5
V-
-0.5
COMMON - MODE VOLTAGE LIMITS (V)
-55 -25 0 25 50 12510075
≈≈
V
S
= ± 2.5 V
TRANSFER FUNCTION
DIFFERENTIAL INPUT VOLTAGE (mV)
+5.0
-5.0
0.0
OUTPUT VOLTAGE (V)
+2.5
0.0
-2.5
TA = 25°C
ALD2331A/ALD2331B/ALD2331 Advanced Linear Devices 4 of 8
COMMON MODE REJECTION RATIO
vs. TEMPERATURE
COMMON MODE REJECTION MODE 
(dB)
-55 -25 025 50 12510075
85.0
80.0
75.0
70.0
90.0
65.0
60.0
AMBIENT TEMPERATURE (°C)
V
+
= +5V
R
L
= 5.1KΩ
POWER SUPPLY REJECTION RATIO 
vs.TEMPERATURE
AMBIENT TEMPERATURE (0C)
-55 -25 0 25 50 100 12575
90.0
85.0
70.0
POWER SUPPLY REJECTION RATIO 
(dB)
80.0
75.0
65.0
60.0
V+ = +5V
RL = 5.1KΩ
INPUT OFFSET VOLTAGE vs. TEMPERATURE
0.4
0.0
-0.4
0.8
-0.8
-1.2
1.2
-2.0
INPUT OFFSET VOLTAGE (mV)
-55 -25 0 25 50 12510075
AMBIENT TEMPERATURE (°C)
-1.6
2.0
1.6 R
L
= 5.1KΩ
V
+
= +5V
V
+
= +2.5V
0.0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3.0
-1.0
0.0
1.0
2.0
3.0
4.0
5.0
6.0
RESPONSE TIME FOR VARIOUS INPUT 
 OVERDRIVES
OUTPUT VOLTAGE
(V)
TIME (µS)
50mV
20mV
10mV
5mV 2mV 1mV
V
+
= +5V
R
L
= 5.1KΩInput StepC
L
= 15pF
T
A
= 25
0
C
SATURATION VOLTAGE vs. SINK CURRENT
OUTPUT SINK CURRENT (mA)
015 30 45 60 75
OUTPUT SATURATION VOLTAGE (V)
3.0
2.0
1.0
0.0
2.5
1.5
0.5
V
+
= +5V T
A
= 1250C
T
A
= -550C
T
A
= 850C
T
A
= 250C
T
A
= -250C
OUTPUT OFF-STATE VOLTAGE vs.
OUTPUT LEAKAGE CURRENT
34567891011
0.0
0.1
1.0
10.0
100.0 VOH = V+
OUTPUT LEAKAGE CURRENT (nA)
OUTPUT OFF-STATE VOLTAGE (V)
T
A
= 125
0
C
T
A
= 85
0
C
T
A
= 25
0
C
TYPICAL PERFORMANCE CHARACTERISTICS (cont'd)
ALD2331A/ALD2331B/ALD2331 Advanced Linear Devices 5 of 8
+
-
+5V
V
A
= 0V to +10V
+10V
0
V
OUT
V
IN+
V
IN-
V
OUT
VOLTAGE COMPARATOR WITH SINGLE
SUPPLY AND OUTPUT LEVEL SHIFT
VOLTAGE COMPARATOR
WITH +/-5V SUPPLY AND +5V RELAY DRIVE
PRECISION SINGLE SUPPLY VOLTAGE
COMPARATOR WITH DIRECT RELAY DRIVER
6810 12
4
2SUPPLY VOLTAGE (V)
OUTPUT LOW VOLTAGE
vs. SUPPLY VOLTAGE
OUTPUT LOW VOLTAGE (V)
TA = 25°C
IOL= 12mA
0.0
0.2
0.4
0.5
0.6
0.1
0.3
TYPICAL APPLICATIONS
+5
5V
RELAY
+
-
+5
V
IN
V
R
+
-
5V
RELAY
-5
+5
V
IN+
1K
V
IN-
-
-
+
+Q
Q
VIN
VREF
V+
VOLTAGE COMPARATOR WITH
COMPLEMENTARY OUTPUTS
RESPONSE TIME FOR VARIOUS INPUT 
 OVERDRIVES
OUTPUT VOLTAGE
(V)
-1.0
6.0
2.0
0.0
1.0
3.0
4.0
5.0
0.0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3.0
TIME (µS)
T
A
= 25
0
C
V
+
= +5V
1mV
2mV
5mV
10mV
20mV
50mV
R
L
= 5.1KΩ
C
L
= 15pF
Input Step
TYPICAL PERFORMANCE CHARACTERISTICS (cont'd)
ALD2331A/ALD2331B/ALD2331 Advanced Linear Devices 6 of 8
VOLTAGE COMPARATOR WITH OUTPUT LEVEL
SHIFT AND HIGH CURRENT LOAD DRIVER
VOLTAGE COMPARATOR WITH +/-5V
SUPPLY AND OUTPUT LEVEL SHIFT
+
-
15K
-5V
+5V
V
OUT
15K
100K
100K
0.1µF
0.1µF
+5V
0
V
OUT
+5V
+
-
-5V
+5V
R
2
=50 200Ω
+5V
R
1
= 15K
R
Load
V
OUT
V
IN+
V
IN-
0.066V
-4V
V
OUT
RESPONSE TIME MEASUREMENT CIRCUIT
Response time is defined as the internal between the application of
an input step function and the instant when the output reaches 50%
of its maximum value as measured by the following test circuit:
+
-5.1KΩ
OUT
+5V
10X INPUT STEP
1KΩ
9KΩ
VIN
DUAL LIMIT WINDOW COMPARATOR
+
+
-
-
OUTPUT HIGH FOR VIN <
VREF(HIGH)
MINIMUM RLOAD
= 1.5KΩ
> AND
VOUT
VIN
V+
VREF(HIGH)
VREF(LOW)
VREF(LOW)
RLOAD
N
DUAL LIMIT PHOTO DETECTOR MONITOR
V+
V
LIMIT2
PHOTO-
DETECTOR
LIGHT
-
-
+
+
LED
BUZZER
V
LIMIT 1
V
External
LED turns on as photo-detector
voltage reaches VLIMIT1. Both LED
and horn turns on as photo-detector
voltage reaches VLIMIT2.
VEXTERNAL= +10V, V+ = +5V
TYPICAL APPLICATIONS (cont'd)
ALD2331A/ALD2331B/ALD2331 Advanced Linear Devices 7 of 8
8 Pin Plastic SOIC Package
Millimeters Inches
Min Max Min MaxDim
A
A1
b
C
D-8
E
e
H
L
S
1.75
0.25
0.45
0.25
5.00
4.05
6.30
0.937
8°
0.50
0.053
0.004
0.014
0.007
0.185
0.140
0.224
0.024
0°
0.010
0.069
0.010
0.018
0.010
0.196
0.160
0.248
0.037
8°
0.020
1.27 BSC 0.050 BSC
1.35
0.10
0.35
0.18
4.69
3.50
5.70
0.60
0°
0.25
ø
SOIC-8 PACKAGE DRAWING
L
C
H
S (45°)
ø
e
A
A
1
b
D
S (45°)
E
ALD2331A/ALD2331B/ALD2331 Advanced Linear Devices 8 of 8
8 Pin Plastic DIP Package
Millimeters Inches
Min Max Min MaxDim
A
A1
A2
b
b1
c
D-8
E
E1
e
e1
L
S-8
ø
3.81
0.38
1.27
0.89
0.38
0.20
9.40
5.59
7.62
2.29
7.37
2.79
1.02
0°
5.08
1.27
2.03
1.65
0.51
0.30
11.68
7.11
8.26
2.79
7.87
3.81
2.03
15°
0.105
0.015
0.050
0.035
0.015
0.008
0.370
0.220
0.300
0.090
0.290
0.110
0.040
0°
0.200
0.050
0.080
0.065
0.020
0.012
0.460
0.280
0.325
0.110
0.310
0.150
0.080
15°
PDIP-8 PACKAGE DRAWING
b
1
S
b
EE1
D
e
A2
A
1
A
L
ce
1
ø