19-1547; Rev 0; 10/99
Low-Cost, Ultra-Small, 3µA
Single-Supply Comparators
Applications
Features
♦ 580ns Propagation Delay from Only 3µA
♦ +2.1V to +5.5V Single-Supply Operation
♦ Ground-Sensing Inputs
♦ Rail-to-Rail Outputs
♦ No Output Phase Inversion for Overdriven Inputs
♦ No Differential Clamp Across Inputs
♦ Available in Ultra-Small Packages
5-Pin SC70 (MAX9075)
8-Pin SOT23 (MAX9077)
Ordering Information
PART
TEMP. RANGE
PINPACKAGE
MAX9075EXK-T
-40°C to +85°C
5 SC70-5
AAC
MAX9075EUK-T
-40°C to +85°C
5 SOT23-5
ADLX
MAX9077EKA-T
-40°C to +85°C
8 SOT23-8
AAAD
MAX9077ESA
-40°C to +85°C
8 SO
TOP
MARK
—
Battery-Powered Systems
Threshold Detectors/Discriminators
Keyless Entry Systems
IR Receivers
Typical Operating Circuit
Digital Line Receivers
VCC
Pin Configurations
TOP VIEW
VIN
VCC
OUT 1
GND 2
5
VCC
MAX9075
MAX9077
IN+
MAX9075
OUT
IN-
IN+ 3
4
INVREF
GND
SC70-5/SOT23-5
Pin Configurations continued at end of data sheet.
________________________________________________________________ Maxim Integrated Products
1
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For small orders, phone 1-800-835-8769.
MAX9075/MAX9077
General Description
The MAX9075/MAX9077 single/dual comparators are
optimized for +3V and +5V single-supply applications.
These comparators have a 580ns propagation delay and
consume just 3µA per comparator. The combination of
low-power, single-supply operation down to +2.1V, and
ultra-small footprint makes these devices ideal for all
portable applications.
The MAX9075/MAX9077 have a common-mode input
voltage range of -0.2V to VCC - 1.2V. Unlike many comparators, there is no differential clamp between the
inputs, allowing the differential input voltage range to
extend Rail-to-Rail®. All inputs and outputs tolerate a
continuous short-circuit fault condition to either rail.
The design of the output stage limits supply-current
surges while switching (typical of many other comparators), minimizing power consumption under dynamic
conditions. Large internal push-pull output drivers allow
rail-to-rail output swing with loads up to 2mA, making
these devices ideal for interface with TTL/CMOS logic.
The MAX9075 single comparator is available in 5-pin
SC70 and SOT23-5 packages, while the MAX9077 dual
comparator is available in 8-pin SOT23-8 and SO
packages.
MAX9075/MAX9077
Low-Cost, Ultra-Small, 3µA
Single-Supply Comparators
ABSOLUTE MAXIMUM RATINGS
Supply Voltage
VCC to GND .....................................................................+6V
All Other Pins to GND...........................-0.3V to (VCC + 0.3V)
Duration of Output Short Circuit to GND or VCC ........Continuous
Continuous Power Dissipation (TA = +70°C)
5-Pin SC70 (derate 2.5mW/°C above +70°C) ............200mW
5-Pin SOT23 (derate 7.1mW/°C above +70°C)..........571mW
8-Pin SOT23 (derate 5.3mW/°C above +70°C)..........421mW
8-Pin SO (derate 5.88mW/°C above +70°C)..............471mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VCC = +5V, VCM = -0.2V, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1)
PARAMETER
SYMBOL
Operating Supply Voltage Range
VCC
Supply Current per Comparator
ICC
CONDITIONS
VCC = 5V
VCC = 5V
MIN
3
TA = +25°C
Common-Mode Voltage Range
PSRR
VCMR
2.1V ≤ VCC ≤ 5.5V
(Note 2)
54
-0.2
VOS
±1
IOS
1
Input Capacitance
CIN
Common-Mode Rejection Ratio
OUT_ Output Voltage High
CMRR
VCM = 0 (Note 3)
-0.2V ≤ VCM ≤ (VCC - 1.2V)
V
5.2
77
Input Offset Current
IB
UNITS
5.5
µA
2.4
Input Offset Voltage
Input Bias Current
MAX
6.6
TA = TMIN to TMAX
VCC = 3V
Power-Supply Rejection Ratio
TYP
2.1
Inferred from PSRR
-5
60
dB
VCC 1.2
V
±8
mV
nA
-20
nA
3
pF
82
dB
VCC 0.4
VOH
ISOURCE = 2mA
OUT_ Output Voltage Low
VOL
ISINK = 2mA
Propagation Delay Low to High
tPD+
CLOAD = 10pF, overdrive = 100mV
580
ns
Propagation Delay High to Low
tPD-
CLOAD = 10pF, overdrive = 100mV
250
ns
CLOAD = 10pF
1.6
ns
Rise/Fall Time
V
0.4
V
Note 1: All devices are 100% production tested at TA = +25°C. All temperature limits are guaranteed by design.
Note 2: Inferred from CMRR. Either input can be driven to the absolute maximum limit without output inversion, as long as the other
input is within the input voltage range.
Note 3: Guaranteed by design.
2
_______________________________________________________________________________________
Low-Cost, Ultra-Small, 3µA
Single-Supply Comparators
OUTPUT VOLTAGE LOW vs.
SINK CURRENT (VCC = 3V)
TA = +85°C
MAX9075/7 toc02
TA = +25°C
2.0
1.5
6
TA = +85°C
10
15
5
10
15
20
25
30
35
SINK CURRENT (mA)
SINK CURRENT (mA)
OUTPUT VOLTAGE HIGH vs.
SOURCE CURRENT (VCC = 2.1V)
OUTPUT VOLTAGE HIGH vs.
SOURCE CURRENT (VCC = 3V)
TA = -40°C
3.0
1.5
TA = +85°C
1.0
TA = +25°C
0.5
TA = -40°C
2.5
TA = +85°C
TA = +25°C
1.0
-0.5
4
6
8 10 12 14
SOURCE CURRENT (mA)
16
VCC = 5V
60
50
40
VCC = 3V
30
20
90
50
40
0
5
25
VCC = 3V
30
0
45
TEMPERATURE (°C)
65
0
85
10 20 30 40 50 60 70 80 90 100
SOURCE CURRENT (mA)
SUPPLY CURRENT vs.
TEMPERATURE (OUT = HIGH)
60
10
-15
45
70
20
VCC = 2.1V
-35
VCC = 5V
80
10
-55
40
100
SOURCE CURRENT (mA)
SINK CURRENT (mA)
70
15 20 25 30 35
SOURCE CURRENT (mA)
SHORT-CIRCUIT SOURCE CURRENT
vs. TEMPERATURE
MAX9075 toc07
80
10
TA = +25°C
1
0
SHORT-CIRCUIT SINK CURRENT
vs. TEMPERATURE
90
2
-1
5
TA = +85°C
3
0
0
90
4
-0.5
18
80
TA = -40°C
4.5
MAX9075 toc08
2
30 40 50 60 70
SINK CURRENT (mA)
5
4.0
SUPPLY CURRENT (µA)
0
20
6
0.5
0
10
OUTPUT VOLTAGE HIGH vs.
SOURCE CURRENT (VCC = 5V)
2.0
1.5
0
OUTPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
TA = -40°C
40
MAX9075/7 toc05
2.0
3.5
MAX9075/7 toc04
2.5
TA = +85°C
2
0
0
20
TA = +25°C
3
MAX9075 toc09
5
4
1
0
0
5
TA = -40°C
0.5
0
OUTPUT VOLTAGE (V)
2.5
1.0
TA = -40°C
0.5
3.0
MAX9075/7 toc06
TA = +25°C
1.5
7
OUTPUT VOLTAGE (V)
2.0
1.0
3.5
OUTPUT VOLTAGE (V)
2.5
OUTPUT VOLTAGE (V)
4.0
MAX9075/7 toc01
3.0
OUTPUT VOLTAGE LOW vs.
SINK CURRENT (VCC = 5V)
MAX9075/7 toc03
OUTPUT VOLTAGE LOW vs.
SINK CURRENT (VCC = 2.1V)
3.5
VCC = 5V
3.0
VCC = 3V
2.5
2.0
VCC = 2.1V
1.5
1.0
VCC = 2.1V
0.5
-55
-35
-15
5
25
45
TEMPERATURE (°C)
65
85
0
-55
-35
-15
5
25
45
65
85
TEMPERATURE (°C)
_______________________________________________________________________________________
3
MAX9075/MAX9077
Typical Operating Characteristics
(VCC = +5V, VCM = 0, 100mV overdrive, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VCC = +5V, VCM = 0, 100mV overdrive, TA = +25°C, unless otherwise noted.)
SUPPLY CURRENT vs.
OUTPUT TRANSITION FREQUENCY
SUPPLY CURRENT (µA)
VCC = 5V
2.5
VCC = 3V
2.0
VCC = 2.1V
1.5
100
-0.1
OFFSET VOLTAGE (mV)
3.0
0
MAX9075 toc11
3.5
SUPPLY CURRENT (µA)
1000
MAX9075 toc10
4.0
INPUT OFFSET VOLTAGE
vs. TEMPERATURE
VCC = 5V
VCC = 3V
10
MAX9075 toc12
SUPPLY CURRENT vs.
TEMPERATURE (OUT = LOW)
1.0
-0.2
-0.3
-0.4
VCC = 5V
-0.5
VCC = 3V
-0.6
VCC = 2.1V
0.5
-0.8
1
-15
5
25
45
65
1
85
10
100
1k
10k
100k
1M
25
45
65
PROPAGATION DELAY
vs. INPUT OVERDRIVE (tPD+)
PROPAGATION DELAY
vs. INPUT OVERDRIVE (tPD-)
0.2
0.1
0.7
1.0
0.8
VCC = 5V
VCC = 3V
0.6
0.4
0.6
PROPAGATION DELAY
vs. TEMPERATURE (VCC = 2.1V)
350
tPD-
300
250
200
150
100
150
200
250
25
45
TEMPERATURE (°C)
65
85
150
200
PROPAGATION DELAY
vs. TEMPERATURE (VCC = 5V)
500
tPD+
400
300
tPD-
200
800
700
tPD+
600
250
500
400
300
tPD-
200
100
0
5
100
PROPAGATION DELAY
vs. TEMPERATURE (VCC = 3V)
100
-15
50
INPUT OVERDRIVE (mV)
50
0
0
INPUT OVERDRIVE (mV)
600
PROPAGATION DELAY (ns)
400
100
PROPAGATION DELAY (ns)
tPD+
50
MAX9075 toc17
450
MAX9075 toc16
500
0.2
0
0
2000
VCC = 2.1V
VCC = 3V
VCC = 5V
0.3
0.1
0
500
1000
1500
LOAD CAPACITANCE (pF)
0.4
VCC = 2.1V
0.2
0
0.5
MAX9075 toc18
tPD-
1.2
85
MAX9075 toc15
1.4
PROPAGATION DELAY (µs)
0.4
0.3
1.6
MAX9075 toc13
0.5
-35
5
PROPAGATION DELAY
vs. LOAD CAPACITANCE
0.6
-55
-15
TEMPERATURE (°C)
tPD+
0
-35
TRANSITION FREQUENCY (Hz)
0.7
4
-55
TEMPERATURE (°C)
PROPAGATION DELAY (µs)
-35
MAX9075 toc14
-55
PROPAGATION DELAY (µs)
-0.7
VCC = 2.1V
0
PROPAGATION DELAY (ns)
MAX9075/MAX9077
Low-Cost, Ultra-Small, 3µA
Single-Supply Comparators
0
-55
-35
-15
5
25
45
TEMPERATURE (°C)
65
85
-55
-35
-15
5
25
45
TEMPERATURE (°C)
_______________________________________________________________________________________
65
85
Low-Cost, Ultra-Small, 3µA
Single-Supply Comparators
PROPAGATION DELAY (tPD+)
PROPAGATION DELAY (tPD-)
MAX9075/7 toc20
MAX9075/7 toc19
VCC = 5V
VCC = 5V
VIN
VIN
50mV/div
50mV/div
VOUT
2V/div
2V/div
VOUT
100ns/div
100ns//div
PROPAGATION DELAY (tPD+)
PROPAGATION DELAY (tPD-)
MAX9075/7 toc22
MAX9075/7 toc23
VCC = 3V
VCC = 3V
VIN
VIN
50mV/div
50mV/div
VOUT
1V/div
VOUT
1V/div
100ns/div
100ns/div
INPUT BIAS CURRENT
vs. TEMPERATURE
TRIANGLE WAVE
MAX9075/7 toc21
MAX9075 toc24
7
VCC = 3V
50mV/div
VIN
VOUT
1V/div
INPUT BIAS CURRENT (nA)
6
VCC = 5V
5
VCC = 3V
4
VCC = 2.1V
3
2
1
0
200µs/div
-55
-35
-15
5
25
45
65
85
TEMPERATURE (°C)
_______________________________________________________________________________________
5
MAX9075/MAX9077
Typical Operating Characteristics (continued)
(VCC = +5V, VCM = 0, 100mV overdrive, TA = +25°C, unless otherwise noted.)
Low-Cost, Ultra-Small, 3µA
Single-Supply Comparators
MAX9075/MAX9077
Pin Description
PIN
MAX9075
NAME
MAX9077
FUNCTION
SOT23-5
SC70-5
SO
SOT23-8
1
1
—
—
OUT
—
—
1
1
OUTA
Output of Comparator A
2
2
4
2
GND
Ground
3
3
—
—
IN+
Noninverting Comparator Input
—
—
3
4
INA+
4
4
—
—
IN-
—
—
2
3
INA-
Inverting Input of Comparator A
5
5
8
8
VCC
Positive Supply Voltage
—
—
5
5
INB+
Noninverting Input of Comparator B
—
—
6
6
INB-
Inverting Input of Comparator B
—
—
7
7
OUTB
Detailed Description
The MAX9075/MAX9077 feature a 580ns propagation
delay from an ultra-low supply current of only 3µA per
comparator. These devices are capable of single-supply operation in the +2.1V to +5.5V range. Large internal output drivers allow rail-to-rail output swing with up
to 2mA loads. Both comparators offer a push-pull output that sinks and sources current.
Comparator Output
The MAX9075/MAX9077 are designed to maintain a
low supply current during repeated transitions by limiting the shoot-through current.
Noise Considerations, Comparator Input
The input common-mode voltage range for these
devices extends from -0.2V to VCC - 1.2V. Unlike many
other comparators, the MAX9075/MAX9077 can operate at any differential input voltage within these limits.
Input bias current is typically -5nA if the input voltage is
between the supply rails.
Although the comparators have a very high gain, useful
gain is limited by noise. The comparator has a wideband peak-to-peak noise of approximately 70µV.
Comparator Output
Noninverting Input of Comparator A
Inverting Comparator Input
Output of Comparator B
Applications Information
Adding Hysteresis
Hysteresis extends the comparator’s noise margin by
increasing the upper threshold and decreasing the
lower threshold. A voltage divider from the output of the
comparator sets the trip voltage. Therefore, the trip
voltage is related to the output voltage. Set the hysteresis with three resistors using positive feedback, as
shown in Figure 1.
The design procedure is as follows:
1) Choose R3. The leakage current of IN+ may cause a
small error; however, the current through R3 can be
approximately 500nA and still maintain accuracy.
The added supply current due to the circuit at the
trip point is VCC/R3; 10MΩ is a good practical value
for R3, as this keeps the current well below the supply current of the chip.
2) Choose the hysteresis voltage (VHYS), which is the
voltage between the upper and lower thresholds. In
this example, choose V HYS = 50mV and assume
VREF = 1.2V and VCC = 5V.
3) Calculate R1 as follows:
R1 = R3 · VHYS / VCC = 10MΩ · 0.05 / 5 = 100kΩ
6
_______________________________________________________________________________________
Low-Cost, Ultra-Small, 3µA
Single-Supply Comparators
R2 = 1 / {[VTHR / (VREF · R1)] - 1/R1 - 1/R3} =
1 / {[3 / (1.2 · 100k)] - 1/100k - 1/10M} = 67.114kΩ
VCC
R3
R1
VIN
VCC
A 1% preferred value is 64.9kΩ.
6) Verify the threshold voltages with these formulas:
VIN rising:
OUT
R2
GND
MAX9075
MAX9077
VREF
VTHR = VREF · R1 (1/R1 + 1/R2 + 1/R3)
VIN falling:
VTHF = VTHR - (R1 · VCC) / R3
Figure 1. Adding Hysteresis
7) Check the error due to input bias current (5nA). If the
error is too large, reduce R3 and recalculate.
Pin Configurations (cont.)
VTH = IB (R1 · R2 · R3) / (R1 + R2 + R3) = 0.2mV
Board Layout and Bypassing
Use 10nF power-supply bypass capacitors. Use 100nF
bypass capacitors when supply impedance is high,
when supply leads are long, or when excessive noise is
expected on the supply lines. Minimize signal trace
lengths to reduce stray capacitance. Minimize the
capacitive coupling between IN- and OUT. For slowmoving input signals (rise time > 1ms) use a 1nF
capacitor between IN+ and IN-.
Chip Information
TOP VIEW
OUTA 1
8
VCC
7
OUTB
GND
2
INA-
3
6
INB-
INA+ 4
5
INB+
OUTA 1
8
VCC
INA- 2
7
OUTB
3
6
INB-
GND 4
5
INB+
TRANSISTOR COUNT: 86 (MAX9075)
142 (MAX9077)
MAX9077
SOT23-8
INA+
MAX9077
SO
_______________________________________________________________________________________
7
MAX9075/MAX9077
4) Choose the threshold voltage for VIN rising (VTHR). In
this example, choose VTHR = 3V.
5) Calculate R2 as follows:
MAX9075/MAX9077
Low-Cost, Ultra-Small, 3µA
Single-Supply Comparators
SOT23, 8L.EPS
SC70, 5L.EPS
Package Information
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 1999 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.