For pricing delivery, and ordering information please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
General Description
The MAX965–MAX970 single/dual/quad micropower
comparators feature rail-to-rail inputs and outputs, and
fully specified single-supply operation down to +1.6V.
These devices draw less than 5µA per comparator and
have open-drain outputs that can be pulled beyond VCC
to 6V (max) above ground. In addition, their rail-to-rail
input common-mode voltage range makes these com-
parators suitable for ultra-low-voltage operation.
A +1.6V to +5.5V single-supply operating voltage range
makes the MAX965 family of comparators ideal for 2-cell
battery-powered applications. The MAX965/MAX967/
MAX968/MAX969 offer programmable hysteresis and
an internal 1.235V ±1.5% reference. All devices are
available in either space-saving 8-pin µMAX®or 16-pin
QSOP packages.
________________________Applications
2-Cell Battery-Powered/Portable Systems
Window Comparators
Threshold Detectors/Discriminators
Mobile Communications
Voltage-Level Translation
Ground/Supply-Sensing Applications
____________________________Features
♦Ultra-Low Single-Supply Operation down to +1.6V
♦Rail-to-Rail Common-Mode Input Voltage Range
♦3µA Quiescent Supply Current per Comparator
♦Open-Drain Outputs Swing Beyond VCC
♦1.235V ±1.5% Precision Internal Reference
(MAX965/967/968/969)
♦10µs Propagation Delay (50mV overdrive)
♦Available in Space-Saving Packages:
8-Pin µMAX (MAX965–MAX968)
16-Pin QSOP (MAX969/MAX970)
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
________________________________________________________________ Maxim Integrated Products 1
VCC
VOUT
7
OUT
GND
1.235V
REF6
HYST
1
5
IN-4
IN+3
8
VCC
VIN
RPULLUP
MAX965
PART TEMP RANGE PIN-
PACKAGE
PKG
CODE
MAX965ESA -40°C to +85°C 8 SO S8-2
MAX965EUA-T -40°C to +85°C 8 µMAX-8 U8-1
MAX966ESA -40°C to +85°C 8 SO S8-2
MAX966EUA-T -40°C to +85°C 8 µMAX-8 U8-1
MAX967ESA -40°C to +85°C 8 SO S8-2
MAX967EUA-T -40°C to +85°C 8 µMAX-8 U8-1
__________Typical Operating Circuit
19-1226; Rev 3; 2/07
Ordering Information
PART
INTERNAL
REFERENCE
PROGRAMMABLE
HYSTERESIS
MAX965 Yes Yes
MAX966 No No
MAX967 Yes Yes
MAX968 Yes Yes
MAX969 Yes Yes
MAX970 No No
COMPARATORS
PER
PACKAGE
1
2
2
2
4
4
_____________________Selector Guide
Ordering Information continued on last page.
Pin Configurations appear at end of data sheet.
µMAX is a registered trademark of Maxim Integrated Products,
Inc.
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VCC = +1.6V to +5.5V, TA= TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3V and TA= +25°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.
Supply Voltage (VCC) ............................................................+6V
Voltages
IN_-, IN_+, REF, HYST ..........................-0.3V to (VCC + 0.3V)
OUT_ ...............................................................-0.3V to +6.0V
Current into Input Pins ......................................................±20mA
Duration of OUT_ Short Circuit to GND or VCC ..........Continuous
Continuous Power Dissipation
8-Pin SO (derate 5.88mW/°C above +70°C)...............471mW
8-Pin µMAX (derate 4.10mW/°C above +70°C) ..........330mW
14-Pin SO (derate 8.33mW/°C above +70°C).............667mW
16-Pin SO (derate 8.70mW/°C above +70°C).............696mW
16-Pin QSOP (derate 5.70mW/°C above +70°C)........457mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
6.0
10.00°C to +85°C
µMAX
package
QSOP package
-40°C to +85°C
Input Offset Voltage VOS
-40°C to +85°C
0°C to +85°C
QSOP package
SO package 3.0
Common-mode
range = -0.25V
to 1.3V,
VCC > 1.8V
mV
V
-0.25 VCC - 0.25
TA= -40°C to +85°C
SO/QSOP packages, TA= -40°C to +85°C
Full common-mode range, TA= +25°C
Common-mode range = -0.25V to (VCC - 0.25V)
All packages, TA= 0°C to +85°C
VCC stepped 0V to 5V
MAX970
MAX966
MAX967/MAX968
TA= +25°C
MAX969
1.7V ≤VCC ≤5.5V
CONDITIONS
7.0CIN
Input Capacitance pF
0.2IOS
Input Offset Current
0.001 ±50 nA
0.001 ±5
IB
Input Bias Current
4.0
-0.25 VCC
VCMR
Common-Mode Voltage Range V
0.1 1.0
PSRRPower-Supply Rejection Ratio
1.7 5.5VCC
Supply Voltage Range V
1.6 5.5
mV/V
20
Power-Up Time
(VCC to output valid)
11 18
µA
7.0 12
ICC
Supply Current
6.0 10
10 16
14 22
UNITSMIN TYP MAXSYMBOLPARAMETER
4.0
15.0
10.0
Full common-
mode range
7.0
µMAX package, TA= -40°C to +85°C 1.8 5.5
MAX965
Comparator Minimum
Operating Voltage V1.0
µs
pA
HYST = REF mV±1VHYST
Input Hysteresis
2 _______________________________________________________________________________________
COMPARATOR
POWER SUPPLIES
SO package
µMAX
package
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
_______________________________________________________________________________________ 3
3
4
-60
MAX965 SUPPLY CURRENT
vs. TEMPERATURE
MAX965-TOC1b
TEMPERATURE (°C)
SUPPLY CURRENT (µA)
5
7
6
8
9
10
11
12
13
-40 -20 0 20 40 60 80 100
VIN+ > VIN-
VCC = 5.0V
VCC = 2.0V
VCC = 3.0V
4.0
-60
MAX966 SUPPLY CURRENT
vs. TEMPERATURE
MAX965-TOC2b
TEMPERATURE (°C)
SUPPLY CURRENT (µA)
4.5
5.5
5.0
6.0
6.5
7.0
7.5
8.0
8.5
9.0
-40 -20 0 20 40 60 80 100
VIN+ > VIN-
VCC = 5.0V
VCC = 2.0V
VCC = 3.0V
5
-60
MAX967/MAX968 SUPPLY CURRENT
vs. TEMPERATURE
MAX965-TOC3b
TEMPERATURE (°C)
SUPPLY CURRENT (µA)
6
8
7
9
10
11
12
13
14
15
-40 -20 0 20 40 60 80 100
VIN+ > VIN-
VCC = 5.0V
VCC = 2.0V
VCC = 3.0V
ELECTRICAL CHARACTERISTICS (continued)
(VCC = +1.6V to +5.5V, TA= TMIN to TMAX, unless otherwise noted. Typical values are at VCC = 3V and TA= +25°C.)
f = 100Hz to 100kHz, CREF = 0.1µF
HYST = REF
SO package
CONDITIONS
µVRMS
10Output Voltage Noise
nA200 400IREF-
Sink Current
µA15 50IREF+
Source Current
V
1.125 1.235 1.255
VREF
Reference Voltage
UNITSMIN TYP MAXSYMBOLPARAMETER
1.205 1.235 1.265
__________________________________________Typical Operating Characteristics
(VCC = +3.0V, RPULLUP = 100kΩ, VCM = 0V, TA= +25°C, unless otherwise noted.)
10
CMRRCommon-Mode Rejection Ratio mV/V1.5 4.0
f = 100Hz to 100kHz, CREF = 1000pFInput Voltage Noise enµVRMS
0.2IOUT = 100µA, 1.6V < VCC < 2.7V
OUT Output Voltage Low VOL V
20
Propagation Delay tPD- µs
10
RPULLUP = 1MΩ,
CLOAD = 15pF, high to low
10mV overdrive
50mV overdrive
QSOP package
HYST Input Voltage Range V
VREF -
0.05 VREF
IHYST
HYST Input Leakage nA±10
Hysteresis Gain V/V1.0
µMAX package, TA= -40°C to +85°C 1.185 1.235 1.285
µMAX package, TA= 0°C to +85°C 1.205 1.235 1.265
0.4IOUT = 500µA, 2.7V < VCC < 5.5V
VCC = 5.5V, VOUT = 5.5V
OUT Output Leakage Current ILEAK nA1 100
VCC = 1.6V, VOUT = 1.6V
REFERENCE
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
4 _______________________________________________________________________________________
0
0
MAX965 SUPPLY CURRENT
vs. SUPPLY VOLTAGE
(INCLUDES REFERENCE CURRENT)
MAX965/70-TOC7a
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (µA)
2
4
6
8
10
12
14
123 4 5 6
VIN+ > VIN-
-60 -20 0-40 20 40 60 80 100
COMPARATOR OUTPUT SHORT-CIRCUIT
SINK CURRENT vs. TEMPERATURE
MAX965/70 -TOC8a
TEMPERATURE (°C)
OUTPUT SHORT-CIRCUIT SINK CURRENT (mA)
VCC = 2V
VCC = 3V
VIN+ < VIN-
VCC = 5V
0
2
4
6
8
10
12
14
0
1.5
1.0
0.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
042681012
COMPARATOR OUTPUT
LOW VOLTAGE vs. SINK CURRENT
MAX965/70-09a
SINK CURRENT (mA)
OUTPUT LOW VOLTAGE (V)
VIN+ = < VIN-
VCC = 5V
VCC = 3V
VCC = 2V
6
-60
PROPAGATION DELAY (tPD-)
vs. TEMPERATURE
MAX965-TOC10a
TEMPERATURE (°C)
DELAY (µs)
7
4
5
9
8
10
11
12
13
14
-40 -20 0 20 40 60 80 100
VOD = 50mV
VCC = 2.0V
VCC = 5.0V VCC = 3.0V
70
0
0.001 0.01 0.1
PROPAGATION DELAY (tPD-)
vs. CAPACITIVE LOAD
10
MAX4108/9-11a
CAPACITIVE LOAD
(µ
F
)
DELAY (µs)
30
20
40
50
60
VOD = 50mV
VCC = 5.0V
VCC = 3.0V
VCC = 2.0V
0
0
PROPAGATION DELAY (tPD-)
vs. INPUT OVERDRIVE
MAX965-TOC12a
INPUT OVERDRIVE (mV)
DELAY (µs)
10
5
15
20
25
30
20 40 60 80 100 120 140 160
VCC = 5.0V
VCC = 2.0V VCC = 3.0V
_____________________________Typical Operating Characteristics (continued)
(VCC = +3.0V, RPULLUP = 100kΩ, VCM = 0V, TA= +25°C, unless otherwise noted.)
8
-60
MAX969 SUPPLY CURRENT
vs. TEMPERATURE
MAX965-TOC4b
TEMPERATURE (°C)
SUPPLY CURRENT (µA)
12
10
14
16
18
20
-40 -20 0 20 40 60 80 100
VIN+ > VIN-
VCC = 5.0V
VCC = 2.0V
VCC = 3.0V
7
-60
MAX970 SUPPLY CURRENT
vs. TEMPERATURE
MAX965-TOC5b
TEMPERATURE (°C)
SUPPLY CURRENT (µA)
8
10
9
11
12
13
14
15
16
-40 -20 0 20 40 60 80 100
VIN+ > VIN-
VCC = 2.0V
VCC = 3.0V
VCC = 5.0V
0
0
SUPPLY CURRENT PER COMPARATOR
vs. SUPPLY VOLTAGE
(EXCLUDES REFERENCE CURRENT)
MAX965-TOC6b
SUPPLY VOLTAGE (V)
SUPPLY CURRENT PER COMPARATOR (µA)
0.5
1.0
1.5
2.0
2.5
3.0
3.5
123456
VIN+ > VIN-
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
_______________________________________________________________________________________ 5
4.0
3.8
2.0
0.01 0.1 1 10 100
SUPPLY CURRENT PER COMPARATOR
vs. OUTPUT TRANSITION FREQUENCY
2.4
2.2
MAX965/70 TOC13A
OUTPUT TRANSITION FREQUENCY (kHz)
SUPPLY CURRENT PER COMPARATOR (µA)
2.8
2.6
3.2
3.0
3.6
3.4
VCC = 5.5V
VCC = 1.6V
100
120
110
140
130
160
150
170
190
180
200
-60 -20 0-40 20 40 60 80 100
INPUT OFFSET VOLTAGE
vs. TEMPERATURE
MAX965/70-TOC14a
TEMPERATURE (°C)
INPUT OFFSET VOLTAGE (µV)
0
1.0
0.5
2.0
1.5
3.5
3.0
2.5
4.0
-40-200 20406080100
INPUT BIAS CURRENT
vs. TEMPERATURE
MAX965/70-TOC15a
TEMPERATURE (°C)
INPUT BIAS CURRENT (pA)
VCC = 5.0V
VCC = 3.0V
0
10
5
15
30
35
25
20
40
0 1.0 1.5 2.0 2.50.5 3.0 3.5 4.0 4.5 5.0
PROGRAMMED HYSTERESIS
vs. COMMON-MODE VOLTAGE
MAX965/70 TOC16
COMMON-MODE VOLTAGE (V)
PROGRAMMED HYSTERESIS (mV)
VCC = 5.0V
VHYST = 22mV (PROGRAMMED)
1.2320
1.2325
1.2335
1.2330
1.2340
1.2345
-60 -20 0-40 20406080100
REFERENCE VOLTAGE
vs. TEMPERATURE
MAX965/70 TOC6a
TEMPERATURE (°C)
REFERENCE VOLTAGE (V)
VCC = 5V
VCC = 3V
VCC = 2V
1.223
1.229
1.227
1.225
1.231
1.233
1.237
1.235
1.239
1.0 1.8 2.6 3.4 4.2 5.0 5.8
REFERENCE VOLTAGE
vs. SUPPLY VOLTAGE
MAX965/70-TOC13
VCC (V)
REFERENCE VOLTAGE (V)
0.6
0.8
0.7
1.0
0.9
1.3
1.2
1.1
1.4
0200100 300 400 500 600 700
REFERENCE VOLTAGE
vs. SOURCE CURRENT
MAX965/70-TOC18a
SOURCE CURRENT (µA)
REFERENCE VOLTAGE (V)
_____________________________Typical Operating Characteristics (continued)
(VCC = +3.0V, RPULLUP = 100kΩ, VCM = 0V, TA= +25°C, unless otherwise noted.)
IN+
OUT
PROPAGATION DELAY (tPD+)
MAX965/70-TOC15
2µs/div
VCC = 3V
50mV/div
2V/div
50mV/div
2V/div
IN+
OUT
PROPAGATION DELAY (tPD-)
MAX965/70-TOC16b
2µs/div
VCC = 3V
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
6 _______________________________________________________________________________________
_____________________________________________________________Pin Descriptions
FUNCTION
PIN
MAX965 MAX966
— 1 Comparator A Open-Drain Output
1 2 Ground
2 — No Connection. Not internally connected.
— 4 Comparator A Inverting Input
4 — Comparator Inverting Input
— 3 Comparator A Noninverting Input
3 — Comparator Noninverting Input
7 7 Positive Supply Voltage, +1.6V to +5.5V
6 — Internal Reference Output. Typically 1.235V with respect to GND.
5 — Hysteresis Input. Connect HYST to REF if not used. Input voltage range
is from VREF to (VREF - 50mV).
— 6 Comparator B Noninverting Input
— 5 Comparator B Inverting Input
MAX967
1
2
—
—
—
3
—
7
6
5
4
—
MAX968
1
2
—
—
—
3
—
7
6
5
—
4
NAME
OUTA
GND
N.C.
INA-
IN-
INA+
IN+
VCC
REF
HYST
INB+
INB-
8 — — — OUT Comparator Open-Drain Output
— 8 8 8 OUTB Comparator B Open-Drain Output
MAX965–MAX968
50mV/div
1V/div
IN+
OUT
10kHz RESPONSE
MAX965/70-TOC18
20µs/div
2V/div
2V/div
VCC
OUT
POWER-UP/DOWN RESPONSE
MAX965/70-TOC17
5µs/div
_____________________________Typical Operating Characteristics (continued)
(VCC = +3.0V, RPULLUP = 100kΩ, VCM = 0V, TA= +25°C, unless otherwise noted.)
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
_______________________________________________________________________________________ 7
________________________________________________Pin Descriptions (continued)
_______________Detailed Description
The MAX965–MAX970 single/dual/quad, micropower,
ultra-low-voltage comparators feature rail-to-rail inputs
and outputs and an internal 1.235V ±1.5% bandgap
reference. These devices operate from a single +1.6V
to +5.5V supply voltage range, and consume less than
5µA supply current per comparator over the extended
temperature range. Internal hysteresis is programmable
up to ±50mV using two external resistors and the
device’s internal reference. The rail-to-rail input com-
mon-mode voltage range and the open-drain outputs
allow easy voltage-level conversion for multivoltage
systems. All inputs and outputs can tolerate a continu-
ous short-circuit fault condition to either rail.
The MAX965 is a single comparator with adjustable
hysteresis and a reference output pin. The MAX966 is a
dual comparator without the reference and without
adjustable hysteresis. The MAX967 is a dual compara-
tor configured as a dual voltage monitor with common
hysteresis adjustment and a reference output. The dual
MAX968 is similar to the MAX967, but is configured as
a window comparator. The MAX969 is a quad com-
parator with a common hysteresis adjustment and a ref-
erence output pin. The MAX970 is a quad comparator
without a reference and without hysteresis adjustment.
(See Functional Diagrams and Selector Guide.)
Comparator Input
The MAX965–MAX970 have a -0.25V to VCC input com-
mon-mode range. Both comparator inputs may operate
at any differential voltage within the common-mode
voltage range, and the comparator displays the correct
output logic state.
Low-Voltage Operation: VCC Down to 1V
The minimum operating voltage is 1.6V. As the supply
voltage falls below 1.6V, performance degrades
and supply current falls. The reference does not
MAX969/MAX970
FUNCTION
MAX969
SO
4 4 Comparator A Inverting Input
3 3 Positive Supply Voltage, +1.6V to +5.5V
2 2 Comparator A Open-Drain Output
1 1 Comparator B Open-Drain Output
8 — Internal Reference Output. Typically 1.235V with respect to GND.
— — No Connection. Not internally connected.
7 7 Comparator B Noninverting Input
6 6 Comparator B Inverting Input
5 5 Comparator A Noninverting Input
MAX970
QSOP
4
3
2
1
—
8, 9
7
6
5
NAME
INA-
VCC
OUTA
OUTB
REF
N.C.
INB+
INB-
INA+
PIN
9 — — HYST Hysteresis Input. Connect to REF if not used. Input voltage range is
from (VREF - 50mV) to VREF.
10 810 INC- Comparator C Inverting Input
11 911 INC+ Comparator C Noninverting Input
12 10 12 IND- Comparator D Inverting Input
13 11 13 IND+ Comparator D Noninverting Input
14 12 14 GND Ground
15 13 15 OUTD Comparator D Open-Drain Output
16 14 16 OUTC Comparator C Open-Drain Output
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
8 _______________________________________________________________________________________
OUTB
OUTA
INA-
INA+
INB-
INB+
REF
OUTC
VCC VCC
OUTD
IND+
IND-
INC+
INC-
+
1.235V
GND HYST
OUTB
OUTA
INA-
INA+
INB-
INB+
OUTC
OUTD
IND+
IND-
INC+
INC-
GND
MAX969 MAX970
VCC VCC
OUT
IN+ OUTA
INA+
GND
GND
GND
INA-
INB+
INB-
OUTB
OUTA
INA+
REF
REF
REF
REF
REF
VCC
VCC
1.235V
1.235V
INB-
HYST
OUTB
OUTA
INA+
REF
INB+
HYST
OUTB
IN-
HYST
REF
+
GND
1.235V
MAX965
MAX968MAX967
MAX966
________________________________________________________Functional Diagrams
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
function below about 1.5V, although the comparators
typically continue to operate with a supply voltage as
low as 1V. At low supply voltages (<1.6V), the input
common-mode range remains rail-to-rail, but the com-
parator’s output sink capability is reduced and propa-
gation delay increases (see Typical Operating
Characteristics).
Figure 1 shows a typical comparator application that
monitors VCC at 1.6V. Resistor divider R1/R2 sets the
voltage trip point (VTRIP) at 1.6V. As VCC drops below
1.6V and approaches 1V, the reference voltage typical-
ly falls below the divider voltage (V+). This causes the
comparator output to change state. If OUT’s state must
be maintained under these conditions, a latching circuit
is required.
Comparator Output
The MAX965–MAX970 contain a unique slew-rate-
controlled output stage capable of rail-to-rail operation
with an external pull-up resistor. Typical comparators
consume orders of magnitude more current during
switching than during steady-state operation. With the
MAX965 family of comparators, during an output transi-
tion from high to low, the output slew rate is limited to
minimize switching current.
Voltage Reference
With VCC greater than 1.6V but less than 5.5V, the inter-
nal 1.235V bandgap reference is ±1.5% accurate over
the commercial temperature range and ±2.5% accu-
rate over the extended temperature range. The REF
output is typically capable of sourcing 50µA. To reduce
reference noise or to provide noise immunity, bypass
REF with a capacitor (0.1nF to 0.1µF).
Noise Considerations
The comparator has an effective wideband peak-to-
peak noise of around 10µV. The voltage reference has
peak-to-peak noise approaching 1.0mV with a 0.1µF
bypass capacitor. Thus, when a comparator is used
with the reference, the combined peak-to-peak noise is
about 1.0mV. This, of course, is much higher than the
individual components’ RMS noise. Avoid capacitive
coupling from any output to the reference pin. Crosstalk
can significantly increase the references’ actual noise.
__________Applications Information
Hysteresis
Many comparators oscillate in the linear region of oper-
ation because of noise or undesired parasitic feed-
back. This tends to occur when the voltage on one
input is equal or very close to the voltage on the other
input. The MAX965–MAX970 have internal hysteresis to
counter parasitic effects and noise. In addition, with the
use of external resistor, the MAX965/MAX967/
MAX968/MAX969’s hysteresis can be programmed to
as much as ±50mV (see the section Adding Hysteresis
to the MAX965/MAX967/MAX968/MAX969).
The hysteresis in a comparator creates two trip points:
one for the rising input voltage and one for the falling
input voltage (Figure 2). The difference between the trip
points is the hysteresis. When the comparator’s input
voltages are equal, the hysteresis effectively causes
one comparator input voltage to move quickly past the
other, thus taking the input out of the region where
oscillation occurs.
THRESHOLDS
OUT
IN-
IN+
VHB
HYSTERESIS
BAND
VREF - VHYST
Figure 2. Threshold Hysteresis Band
REF
GND
VCC
VTRIP = 1.22 + 1
VCC
VREF
OUT
R1
47kΩ
R2
150kΩ
V+
VCC
V+
t
1.6V
1.0V
100kΩ
MAX965 R1
R2
R1 = x R2
- 1
VTRIP
1.22
Figure 1. Operation below 1.6V
_______________________________________________________________________________________ 9
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
10 ______________________________________________________________________________________
HYST
REF
GND
VCC
R1
R2
MAX965
MAX967
MAX968
MAX969
+1.6V TO +5.5V
IREF
Figure 3. Programming the HYST Pin
GND
VCC
VCC
OUT
R3
R1
R2
R4
VREF
VIN
MAX966
MAX970
Figure 4. External Hysteresis
Figure 2 illustrates the case in which IN- has a fixed
voltage applied, and IN+ is varied. If the inputs were
reversed, the figure would be the same, except with an
inverted output.
Adding Hysteresis to the
MAX965/MAX967/MAX968/MAX969
To add hysteresis to the MAX965/MAX967/MAX968/
MAX969, connect resistor R1 between REF and HYST,
and connect resistor R2 between HYST and GND
(Figure 3). If additional hysteresis is not required,
connect HYST to REF. When hysteresis is added, the
upper and lower trip points change by the same
amount in opposite directions. The hysteresis band (the
difference between the upper and lower trip points,
VHB) is approximately twice the voltage between HYST
and REF. The HYST input voltage range is from REF
down to (REF - 50mV). This yields a hysteresis band
from ±1mV to a maximum of ±50mV. Calculate the val-
ues of R1 and R2 for the desired hysteresis band with
the following formulas:
R1 = VHB / IREF
R2 = (VREF - VHB) / IREF
where IREF (the current sourced by the reference) does
not exceed the REF source capability (12µA typical),
and is significantly larger than the HYST leakage cur-
rent (5nA typical). IREF values between 0.1µA and 4µA
are good choices. If 2.4MΩis chosen for R2 (IREF =
0.5µA), the equation for R1 and VHB can be approxi-
mated as:
R1(kΩ) = 2 x VHB (mV)
In the MAX967/MAX968/MAX969, the HYST pin pro-
grams the same hysteresis for all comparators in the
package.
Due to the internal structure of the input developed for
ultra-low-voltage operation, the hysteresis band varies
with common-mode voltage. The graph Programmed
Hysteresis vs. Common-Mode Voltage in the Typical
Operating Characteristics shows this variation. Notice
that the hysteresis band increases to almost twice the
calculated value toward the ends of the common-mode
range. This is apparent only when programming addi-
tional hysteresis using the HYST pin. The hysteresis
band is constant when HYST is connected to REF.
Adding Hysteresis to the MAX966/MAX970
The MAX966/MAX970 do not have a HYST pin for pro-
gramming hysteresis. Hysteresis can be generated with
three resistors using positive feedback (Figure 4). This
method generally draws more current than the method
using the HYST pin on the MAX965/MAX967/MAX968/
MAX969. Also, the positive feedback method slows
hysteresis response time. Use the following procedure
to calculate the resistor values:
1) Select R3. The leakage current of IN+ is under 5nA,
so the current through R3 should be at least 500nA
to minimize errors caused by leakage current. The
current through R3 at the trip point is (VREF - VOUT) /
R3. Taking into consideration the two possible out-
put states and solving for R3 yields two formulas:
R3 = VREF / 500nA
and
R3 = (VREF - VCC) / 500nA
Use the smaller of the two resulting resistor values.
For example, if VREF = 1.2V and VCC = 5.0V, then
the two resistor values are 2.4MΩand 7.6mΩ. For
R3, choose the 2.2MΩstandard value.
2) Choose the hysteresis band required (VHB). For this
example, choose 50mV.
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
______________________________________________________________________________________ 11
3) Calculate R1: R1 = (R3 + R4) x (VHB / VCC). Putting
in the values for this example, R1 = (2.2MΩ+ 10kΩ)
x (50mV / 5.0V) = 22.1kΩ.
4) Choose the trip point for VIN rising. This is the
threshold voltage where the comparator output tran-
sitions from low to high as VIN rises above the trip
point. For this example, choose 3.0V.
5) Calculate R2 as follows:
where VTHR is the rising-voltage trip threshold.
Choose a standard value of 15kΩ.
6) Verify trip voltages and hysteresis as follows:
where VTHR is the rising-voltage trip point, and VTHF
is the falling-voltage trip point.
Circuit Layout and Bypassing
Power-supply bypass capacitors are not needed if sup-
ply impedance is low, but 100nF bypass capacitors
should be used when supply impedance is high or
when supply leads are long. Minimize signal lead
lengths to reduce stray capacitance between the input
and output that might cause instability.
IR Receiver
Figure 5 shows an application using the MAX965 as an
infrared receiver. The infrared photodiode creates a
current relative to the amount of infrared light present.
This current creates a voltage across R1. When this
voltage level crosses the reference voltage applied to
the inverting input, the output transitions. Optional R3
provides additional hysteresis for noise immunity.
2-Cell to TTL Logic-Level Shifter
Figure 6 shows an application using the MAX965
to convert a 2-cell voltage-level signal into a TTL-
compatible signal. The supply voltage for the compara-
tor comes from the 2-cell supply. The output is pulled
up to a 5V supply.
Vrig
VVxRx
RR R R
V falling
VV RxV
RR
Hysteresis V V
IN
THR REF
IN
THF THR CC
THR THF
sin :
:
=++
+
⎛
⎝
⎜⎞
⎠
⎟
=−+
⎛
⎝
⎜⎞
⎠
⎟
=−
11
1
1
2
1
34
1
34
RV
VxR RRR
RV
xk k M k
k
THR
REF
21
1
1
1
1
34
21
30
12 22
1
22
1
22 10
14 76
=⎛
⎝
⎜⎞
⎠
⎟−−+
=⎛
⎝
⎜⎞
⎠
⎟−− +
=
.
.
.
.
ΩΩ ΩΩ
Ω
GND
VCC
VCC
VCC
VCC
0.1µF
OUT
R3
RD
RPULLUP
REF MAX965
HYST
Figure 5. IR Receiver
GND
VCC
+5V
2 CELLS 0.1µF
OUT
INPUT
REF MAX965
HYST
Figure 6. 2-Cell to TTL Logic-Level Translator
TRANSISTOR COUNTS:
MAX965 = 216
MAX966 = 190
MAX967/MAX968 = 299
MAX969 = 465
MAX970 = 380
___________________Chip Information
_Ordering Information (continued)
__________________________________________________________Pin Configurations
14
13
12
11
10
9
8
1
2
3
4
5
6
7
OUTC
OUTD
GND
IND+INA-
VCC
OUTA
OUTB
MAX970
IND-
INC+
INC-
INB+
INB-
INA+
SO
TOP VIEW
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
OUTC
OUTD
GND
IND+INA-
VCC
OUTA
OUTB
MAX969
IND-
INC+
INC-
HYST
REF
INB+
INB-
INA+
SO/QSOP
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
OUTC
OUTD
GND
IND+INA-
VCC
OUTA
OUTB
MAX970
IND-
INC+
INC-
N.C.
N.C.
INB+
INB-
INA+
QSOP
1
2
3
4
OUT
VCC
REF
HYSTIN-
IN+
N.C.
GND
MAX965
SO/µMAX SO/µMAX SO/µMAX
8
7
6
5
1
2
3
4
OUTB
VCC
INB+
INB-INA-
INA+
GND
OUTA
MAX966
8
7
6
5
1
2
3
4
OUTB
VCC
REF
HYSTINB+
(INB-)
INA+
GND
OUTA
MAX967
MAX968
8
7
6
5
( ) ARE FOR MAX968 ONLY.
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
12 ______________________________________________________________________________________
PART TEMP RANGE PIN-
PACKAGE
PKG
CODE
MAX968ESA -40°C to +85°C 8 SO S8-2
MAX968EUA-T -40°C to +85°C 8 µMAX-8 U8-1
MAX969ESE -40°C to +85°C 16 Narrow SO S16-1
MAX969EEE -40°C to +85°C 16 QSOP E16-1
MAX970ESD -40°C to +85°C 14 SO S14-4
MAX970EEE -40°C to +85°C 16 QSOP E16-1
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
______________________________________________________________________________________ 13
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)
PACKAGE OUTLINE, 8L uMAX/uSOP
1
1
21-0036 J
REV.DOCUMENT CONTROL NO.APPROVAL
PROPRIETARY INFORMATION
TITLE:
MAX
0.043
0.006
0.014
0.120
0.120
0.198
0.026
0.007
0.037
0.0207 BSC
0.0256 BSC
A2 A1
c
eb
A
L
FRONT VIEW SIDE VIEW
E H
0.6±0.1
0.6±0.1
Ø0.50±0.1
1
TOP VIEW
D
8
A2 0.030
BOTTOM VIEW
16°
S
b
L
H
E
D
e
c
0°
0.010
0.116
0.116
0.188
0.016
0.005
8
4X S
INCHES
-
A1
A
MIN
0.002
0.950.75
0.5250 BSC
0.25 0.36
2.95 3.05
2.95 3.05
4.78
0.41
0.65 BSC
5.03
0.66
6°0°
0.13 0.18
MAX
MIN
MILLIMETERS
- 1.10
0.05 0.15
α
α
DIM
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.
14 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 2007 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.
MAX965–MAX970
Single/Dual/Quad, Micropower,
Ultra-Low-Voltage, Rail-to-Rail I/O Comparators
Package Information (continued)
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)
SOICN .EPS
PACKAGE OUTLINE, .150" SOIC
1
1
21-0041 B
REV.DOCUMENT CONTROL NO.APPROVAL
PROPRIETARY INFORMATION
TITLE:
TOP VIEW
FRONT VIEW
MAX
0.010
0.069
0.019
0.157
0.010
INCHES
0.150
0.007
E
C
DIM
0.014
0.004
B
A1
MIN
0.053A
0.19
3.80 4.00
0.25
MILLIMETERS
0.10
0.35
1.35
MIN
0.49
0.25
MAX
1.75
0.050
0.016L0.40 1.27
0.3940.386D
D
MINDIM
D
INCHES
MAX
9.80 10.00
MILLIMETERS
MIN MAX
16 AC
0.337 0.344 AB8.758.55 14
0.189 0.197 AA5.004.80 8
N MS012
N
SIDE VIEW
H 0.2440.228 5.80 6.20
e 0.050 BSC 1.27 BSC
C
HE
eBA1
A
D
0∞-8∞
L
1
VARIATIONS:
Revision History
Pages changed at Rev 3: 1-7, 9, 11, 12, 14
