AD ADCMP370 General-purpose comparator Datasheet

General-Purpose Comparators
ADCMP370/ADCMP371
FEATURES
FUNCTIONAL BLOCK DIAGRAMS
VCC
ADCMP370
IN+
OUT
IN–
04745-001
2.25 V to 5.5 V operating voltage range
Low power consumption (4 μA)
High voltage (22 V) tolerance on inputs
Output stages
ADCMP370: open-drain, high voltage (22 V tolerance)
ADCMP371: push-pull
50 nA input bias current
150 nA input offset current
9 mV input offset voltage
Rail-to-rail, common-mode input range
Specified over –40°C to +85°C temperature range
5-lead SC70 packaging
GND
Figure 1.
APPLICATIONS
Voltage detectors
Battery management systems
Analog-to-digital converters
Low voltage applications
Battery-powered electronics
Portable equipment
VCC
ADCMP371
IN+
OUT
GENERAL DESCRIPTION
IN–
GND
04745-002
The ADCMP370/ADCMP371 are general-purpose comparators
with input offset voltages of 9 mV (maximum) and low power
consumption, which make them ideal for battery-powered,
portable equipment.
Figure 2.
The ADCMP371 has a push-pull output stage, while the
ADCMP370 has an open-drain output. The inputs on both
parts and the output on the ADCMP370 can tolerate voltages
up to 22 V, making them suitable for use as voltage detectors in
portable equipment.
The devices are available in space-efficient, 5-lead SC70
packaging.
Rev. A
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rights of third parties that may result from its use. Specifications subject to change without notice. No
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Fax: 781.461.3113
©2006 Analog Devices, Inc. All rights reserved.
ADCMP370/ADCMP371
TABLE OF CONTENTS
Features .............................................................................................. 1
Pin Configuration and Function Descriptions..............................5
Applications....................................................................................... 1
Typical Performance Characteristics ..............................................6
General Description ......................................................................... 1
Applications........................................................................................9
Functional Block Diagrams............................................................. 1
Basic Comparator..........................................................................9
Revision History ............................................................................... 2
Adding Hysteresis..........................................................................9
Specifications..................................................................................... 3
Outline Dimensions ....................................................................... 11
Absolute Maximum Ratings............................................................ 4
Ordering Guide .......................................................................... 11
ESD Caution.................................................................................. 4
REVISION HISTORY
1/06—Rev. 0 to Rev. A
Changes to Features.......................................................................... 1
Changes to Figure 19........................................................................ 9
Changes to Figure 20 Caption....................................................... 10
Updated Outline Dimensions ....................................................... 11
10/04—Revision 0: Initial Version
Rev. A | Page 2 of 12
ADCMP370/ADCMP371
SPECIFICATIONS
VCC = full operating range, TA = −40°C to +85°C, unless otherwise noted.
Table 1.
Parameter
SUPPLY
VCC Operating Voltage Range
Supply Current
COMMON-MODE INPUT RANGE
INPUT OFFSET VOLTAGE
INPUT OFFSET VOLTAGE AVERAGE DRIFT
INPUT BIAS CURRENT
INPUT OFFSET CURRENT
OUT VOLTAGE LOW
OUT VOLTAGE HIGH (ADCMP371)
OUT LEAKAGE CURRENT (ADCMP370)
Output Rise Time
Output Fall Time
TIMING
Propagation Delay
Min
Typ
Max
Unit
Test Conditions/Comments
5.5
7
VCC
9
V
μA
V
mV
μV/°C
nA
nA
V
VIN = VCC /2
VCM = 0 V
VIN = VCC /2
VIN = VCC /2
IN+ < IN−, ISINK = 1.2 mA
V
IN+ > IN−, ISOURCE = 500 μA
30
45
μA
ns
ns
IN+ > IN−, OUT = 22 V
COUT = 15 pF
COUT = 15 pF
5
2
μs
μs
Input overdrive = 10 mV
Input overdrive = 100 mV
2.25
4
0
5
50
150
0.4
0.8 VCC
1
Rev. A | Page 3 of 12
ADCMP370/ADCMP371
ABSOLUTE MAXIMUM RATINGS
TA = 25°C, unless otherwise noted.
Table 2.
Parameter
VCC
IN+, IN−
OUT (ADCMP370)
OUT (ADCMP371)
Operating Temperature Range
Storage Temperature Range
θJA Thermal Impedance, SC70
Lead Temperature
Soldering (10 sec)
Vapor Phase (60 sec)
Infrared (15 sec)
Rating
−0.3 V to +6 V
−0.3 V to +25 V
−0.3 V to +25 V
−0.3 V to VCC + 0.3 V
−40°C to +85°C
−65°C to +150°C
146°C/W
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
300°C
215°C
220°C
ESD CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on
the human body and test equipment and can discharge without detection. Although this product features
proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy
electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance
degradation or loss of functionality.
Rev. A | Page 4 of 12
ADCMP370/ADCMP371
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
1
GND
2
IN–
3
5
VCC
4
OUT
ADCMP370/
ADCMP371
04745-003
IN+
Figure 3. Pin Configuration
Table 3. Pin Function Descriptions
Pin No.
1
2
3
4
5
Mnemonic
IN+
GND
IN–
OUT
VCC
Description
Noninverting Input.
Ground.
Inverting Input.
Comparator Output. Open drain for ADCMP370. Push-pull for ADCMP371.
Power Supply.
Rev. A | Page 5 of 12
ADCMP370/ADCMP371
TYPICAL PERFORMANCE CHARACTERISTICS
30
3.0
25
PROPAGATION DELAY (μs)
2.5
15
10
5
tPHL
2.0
1.5
tPLH
1.0
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
0
–40
04745-006
–5
5.5
CM I/P (V)
Figure 4. Input Offset vs. Common-Mode Input Voltage
125
Figure 7. Propagation Delay vs. Temperature
4.5
4.0
4.0
3.5
tPLH –40°C
3.0
2.5
tPLH +125°C
2.0
tPLH +25°C
1.5
3.0
–40°C
1.5
1.0
0.5
0.5
10
20
30
40
50
60
70
80
90
100 110 120 130
INPUT OVERDRIVE (mV)
+125°C
2.0
1.0
0
+25°C
2.5
0
Figure 5. Propagation Delay vs. Input Overdrive (Low to High)
1
2
3
4
SUPPLY VOLTAGE (V)
5
6
04745-021
SUPPLY CURRENT (μA)
3.5
04745-007
PROPAGATION DELAY (μs)
25
85
TEMPERATURE (°C)
04745-013
0.5
0
6
04745-015
OFFSET (mV)
20
Figure 8. Supply Current vs. Supply Voltage (Output Low)
4.0
6
3.5
SUPPLY CURRENT (μA)
4
tPHL +125°C
3
tPHL +25°C
tPHL –40°C
2
1
0
10
3.0
–40°C
2.5
+125°C
+25°C
2.0
1.5
1.0
0.5
20
30
40
50 60 70 80 90 100 110 120 130
INPUT OVERDRIVE (mV)
0
04745-008
PROPAGATION DELAY (μs)
5
1
2
3
4
SUPPLY VOLTAGE (V)
5
Figure 9. Supply Current vs. Supply Voltage (Output High)
Figure 6. Propagation Delay vs. Input Overdrive (High to Low)
Rev. A | Page 6 of 12
ADCMP370/ADCMP371
1000
900
800
700
700
VCC = 2.25V
600
I BIAS (nA)
OUTPUT LOW VOLTAGE (mV)
900
500
400
500
300
VCC = 3.3V
VCC = 5.5V
300
VCC = 5V
200
100
0
1
2
3
4
5
SINK CURRENT (mA)
–100
5.1
04745-016
0
5.5
1.20
–1.2
1.15
–1.4
1.10
HYSTERESIS (mV)
–1.6
OFFSET (mV)
5.4
Figure 13. Input Bias Current vs. Input Voltage
–1.0
–1.8
–2.2
5.3
VIN (V)
Figure 10. Output Low Voltage vs. Sink Current
–2.0
5.2
04745-023
100
VCC = 2.25V
VCC = 5V
VCC = 3.3V
–2.4
1.05
1.00
0.95
0.90
–2.6
0.85
125
0.80
2.25
Figure 11. Input Offset vs. Temperature
2.75
3.25
3.75
4.25
VCC (V)
4.75
5.25
5.50
04745-027
25
85
TEMPERATURE (°C)
04745-020
–3.0
–40
150
04745-028
–2.8
Figure 14. Hysteresis vs. Supply Voltage
300
3.0
2.5
200
2.0
HYSTERESIS (mV)
250
150
IOUT = 1mA
100
1.5
1.0
VCC = 5V
50
0
–50
0.5
0
50
TEMPERATURE (°C)
100
150
04745-022
OUTPUT LOW VOLTAGE (mV)
IOUT = 2mA
0
–50
Figure 12. Output Low Voltage vs. Temperature
0
50
TEMPERATURE (°C)
100
Figure 15. Hysteresis vs. Temperature
Rev. A | Page 7 of 12
ADCMP370/ADCMP371
CH1 = (IN–) – IN+
1
CH2 = OUT
CH1 = (IN–) – IN+
CH2 = OUT
2
CH1 10mV/DIV
CH2 2.00V/DIV
TIMEBASE: 3.00μs/DIV
04745-029
2
CH1 100mV/DIV CH2 2.00V/DIV
Figure 16. Propagation Delay Timing 10 mV Overdrive
TIMEBASE: 1.00μs/DIV
Figure 17. Propagation Delay Timing 100 mV Overdrive
Rev. A | Page 8 of 12
04745-030
1
ADCMP370/ADCMP371
APPLICATIONS
BASIC COMPARATOR
The upper input threshold level is given by
In its most basic configuration, a comparator can be used to
convert an analog input signal to a digital output signal. The
analog signal on IN+ is compared to the voltage on IN−, and
the voltage at OUT is either high or low, depending on whether
IN+ is at a higher or lower potential than IN−, respectively.
The ADCMP370 and ADCMP371 have different digital output
structures. The ADCMP370 has an open-drain output stage
that requires an external resistor to pull OUT to the logic high
voltage level when the output transistor is switched off. This
voltage level can be as high as 22 V. The same 22 V tolerance
also applies to the inputs of the comparators. The pull-up
resistor should be large enough to avoid excessive power
dissipation but small enough to switch logic levels reasonably
quickly when the comparator output is connected to other
digital circuitry. A suitable value is between 1 kΩ and 10 kΩ.
The ADCMP371 has a push-pull output stage, which has an
internal PMOS pull-up and, therefore, does not require an
external resistor. Faster switching speeds between low and high
rails are possible, but the logic high level is limited to VCC.
VCC
V IN_HI =
VREF ( R1 + R2 ) − VCC R1
R2
The lower input threshold level is given by
V IN_LO =
VREF (R1 + R2 )
R2
The hysteresis is the difference between these voltage levels
VCC R1
R2
ΔV IN =
In the example in Figure 19, Resistor R1 and Resistor R2 are
chosen to give 1 V hysteresis about the reference of 2.5 V, with
VCC = 5 V.
VCC = 5V
ADM331
ADCMP371
IN–
VREF = 2.5V
OUT
IN+
VIN
R1 = 200kΩ
V+
ADM331
ADCMP370
R2 = 1MΩ
VIN
OUT
VREF
VOUT
V+
VIN_LO VIN_HI
= 2V
= 3V
VREF
VIN
Figure 19. Noninverting Comparator Configuration with Hysteresis
0V
t
With the inverting configuration, the upper and lower
switching thresholds are
04745-017
VIN
Figure 18. Basic Comparator and Input and Output Signals
V IN_HI =
ADDING HYSTERESIS
To prevent oscillations at the output caused by noise or slowly
moving signals passing the switching threshold, positive feedback
can be used to add hysteresis to the differential input.
For the noninverting configuration, shown in Figure 19,
two resistors are used to create different switching thresholds,
depending on whether the input signal is increasing or
decreasing in magnitude. When the input voltage is increasing,
the threshold is above VREF, and when it is decreasing, the
threshold is below VREF.
Rev. A | Page 9 of 12
VIN_HI =
VCC R2
(R1 || R3) + R2
VCC × R2( R1 + R3)
(R1 × R3) + (R2 × R1) + (R2 × R3)
V IN_LO =
VIN_LO =
VCC (R2 || R3 )
R1 + (R2 || R3 )
VCC × R2 × R3
(R1 × R3) + (R2 × R1) + (R2 × R3)
04745-018
VOUT
ADCMP370/ADCMP371
VCC = 5V
ADCMP371
R1 = 1MΩ
IN+
OUT
IN–
RLOAD
R3 = 1MΩ
R2 = 1MΩ
VOUT HIGH:
VOUT LOW:
VCC
R1
VCC
R3
R1
VIN_LO
VIN_HI
R2
R2
R3
VOUT
VIN_LO VIN_HI
= 1.67V = 3.33V
VIN
Figure 20. Inverting Comparator Configuration with Hysteresis
Rev. A | Page 10 of 12
04745-019
VIN
ADCMP370/ADCMP371
OUTLINE DIMENSIONS
2.20
2.00
1.80
1.35
1.25
1.15
5
1
4
2
3
2.40
2.10
1.80
PIN 1
0.65 BSC
1.00
0.90
0.70
1.10
0.80
0.30
0.15
0.10 MAX
0.40
0.10
SEATING
PLANE
0.22
0.08
0.46
0.36
0.26
0.10 COPLANARITY
COMPLIANT TO JEDEC STANDARDS MO-203-AA
Figure 21. 5-Lead Thin Shrink Small Outline Transistor Package [SC70]
(KS-5)
Dimensions shown in millimeters
ORDERING GUIDE
Model
ADCMP370AKS-REEL
ADCMP370AKS-REEL7
ADCMP370AKSZ-REEL 1
ADCMP370AKSZ-REEL71
Temperature Range
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
Package Description
5-Lead SC70
5-Lead SC70
5-Lead SC70
5-Lead SC70
Package Option
KS-5
KS-5
KS-5
KS-5
Branding
M1F
M1F
M8P
M8P
ADCMP371AKS-REEL
ADCMP371AKS-REEL7
ADCMP371AKSZ-REEL71
−40°C to +85°C
−40°C to +85°C
−40°C to +85°C
5-Lead SC70
5-Lead SC70
5-Lead SC70
KS-5
KS-5
KS-5
M1G
M1G
M8W
1
Z = Pb-free part.
Rev. A | Page 11 of 12
ADCMP370/ADCMP371
NOTES
©2006 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D04745-0-1/06(A)
Rev. A | Page 12 of 12