Rainbow Electronics MAX944 User Manual

General Description

The MAX941/MAX942/MAX944 are single/dual/quad
high-speed comparators optimized for systems pow­ered from a 3V or 5V supply. These devices combine
high speed, low power, and Rail-to-Rail®inputs.
Propagation delay is 80ns, while supply current is only
350µA per comparator.

The input common-mode range of the MAX941/
MAX942/MAX944 extends beyond both power-supply
rails. The outputs pull to within 0.4V of either supply rail
without external pullup circuitry, making these devices
ideal for interface with both CMOS and TTL logic. All
input and output pins can tolerate a continuous short­circuit fault condition to either rail.

Internal hysteresis ensures clean output switching,
even with slow-moving input signals. The MAX941 fea­tures latch enable and device shutdown.

The single MAX941 and dual MAX942 are offered in a
tiny µMAX package. Both the single and dual MAX942
are available in 8-pin DIP and SO packages. The quad
MAX944 comes in 14-pin DIP and narrow SO pack­ages.

________________________Applications

3V/5V Systems

Battery-Powered Systems

Threshold Detectors/Discriminators

Line Receivers

Zero-Crossing Detectors

Sampling Circuits

____________________________Features

♦ Available in µMAX Package

♦ Optimized for 3V and 5V Applications

(operation down to 2.7V)

♦ Fast, 80ns Propagation Delay (5mV overdrive)

♦ Rail-to-Rail Input Voltage Range

♦ Low Power:

1mW Power Dissipation per Comparator (3V)
350µA Supply Current

♦ Low, 1mV Offset Voltage

♦ Internal Hysteresis for Clean Switching

♦ Outputs Swing 200mV of Power Rails

♦ CMOS/TTL-Compatible Outputs

♦ Output Latch (MAX941 only)

♦ Shutdown Function (MAX941 only)

MAX941/MAX942/MAX944

High-Speed, Low-Power, 3V/5V, Rail-to-Rail,

Single-Supply Comparators

________________________________________________________________ Maxim Integrated Products 1

Pin Configurations

19-0229; Rev 4; 9/01

Ordering Information continued at end of data sheet.

8 SO-40°C to +85°CMAX941ESA

8 Plastic DIP-40°C to +85°CMAX941EPA

8 SO0°C to +70°CMAX941CSA

8 Plastic DIP0°C to +70°C

MAX941CPA

PIN-PACKAGETEMP RANGEPART

8 µMAX-40°C to +85°CMAX941EUA

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.

Rail-to-Rail is a registered trademark of Nippon Motorola Ltd.

Ordering Information

TOP VIEW

MAX941

+

1

V

2

+

IN

3

IN-

4

SHDN

DIP/SO/µMAX

8

N.C.

7

OUT

6

GND

5

LATCH

OUTA

INA-

INA

GND

+

MAX942

1

2

A

3

4

DIP/SO/µMAX

OUTA

1

INA-

8

+

V

7

OUTB

6

INB-

B

5

+

INB

INA

INB

INB-

OUTB

2

AD

+

3

+

V

4

+

MAX944

5

BC

6

7

DIP/SO

14

13

12

11

10

9

8

OUTD

IND-

IND

GND

INC

INC-

OUTC

+

+

MAX941/MAX942/MAX944

High-Speed, Low-Power, 3V/5V, Rail-to-Rail,
Single-Supply Comparators

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V+ = 2.7V to 6.0V, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.) (Note 14)

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.

Power-Supply Ranges

Supply Voltage V+ to GND .............................................+6.5V

Differential Input Voltage ..........................-0.3V to (V+ + 0.3V)

Common-Mode Input Voltage ..................-0.3V to (V+ + 0.3V)

–L—A—T—C—H–

Input (MAX941 only) ....................-0.3V to (V+ + 0.3V)

S—H—D—N–Control Input (MAX941 only) .........-0.3V to (V+ + 0.3V)

Continuous Power Dissipation (T

A

= +70°C)
8-Pin Plastic DIP (derate 9.09mW/°C above +70°C) ...727mW

8-Pin SO (derate 5.88mW/°C above +70°C)................471mW

8-Pin µMAX (derate 4.1mW/°C above +70°C) .............330mW

14-Pin Plastic DIP (derate 10.00mW/°C above +70°C)..800mW

14-Pin SO (derate 8.33mW/°C above +70°C)..............667mW

Operating Temperature Ranges

MAX94_C_ _ .......................................................0°C to +70°C

MAX94_E_ _.....................................................-40°C to +85°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

MAX94_E

MAX94_C

(Note 1)

(Note 6)

I

SINK

= 4mA

I

SINK

= 400µA

VIN= VOS, VCM= 0 or V+

VIN= VOS, VCM= 0 or
VCM= V+ (Note 4)

I

SOURCE

= 4mA

I

SOURCE

= 400µA

CONDITIONS

µA1I

LEAK

Output Leakage Current

V

0.3 0.4

V

OL

Output Low Voltage

0.2 0.4

V

V+ - 0.4 V+ - 0.3

V

OH

Output High Voltage

V+ - 0.4 V+ - 0.2

V-0.2 V+ + 0.2V

CMR

V2.7 6.0V+Positive Supply Voltage

Input Voltage Range

nA10 100I

OS

Input Offset Current

nA

150 400

I

B

Input Bias Current

150 300

UNITSMIN TYP MAXSYMBOLPARAMETER

13

MAX94_C_ _, MAX94_EP_,
MAX94_ES_

TA= +25°C
VCM= 0 or
VCM= V+
(Note 2)

mV

14

MAX941EUA/MAX942EUA

4

Input-Referred Trip
Points

MAX94_C_ _, MAX94_EP_,
MAX94_ES_

TA= T

MIN

to T

MAX

V

TRIP

mV

6MAX941EUA/MAX942EUA

3

Input Offset Voltage

12

MAX94_C_ _, MAX94_EP_,
MAX94_ES_

MAX94_C_ _, MAX94_EP_,
MAX94_ES_

TA= +25°C

TA= T

MIN

to T

MAX

V

OS

mV

5.5MAX941EUA/MAX942EUA

VCM= 0 or
VCM= V+
(Note 3)

mV

13MAX941EUA/MAX942EUA

µV/V

80 300

MAX94_C_ _, MAX94_EP_,
MAX94_ES_

(Note 5)

80 800

CMRR

Common-Mode Rejection
Ratio

MAX941EUA/MAX942EUA

µV/V

80 300

MAX94_C_ _, MAX94_EP_,
MAX94_ES_

2.7V ≤ V+ ≤ 6.0V,
VCM= 0

80 350

PSRR

Power-Supply Rejection
Ratio

MAX941EUA/MAX942EUA

MAX941/MAX942/MAX944

High-Speed, Low-Power, 3V/5V, Rail-to-Rail,

Single-Supply Comparators

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(V+ = 2.7V to 6.0V, TA= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at TA= +25°C.) (Note 14)

Note 1: Inferred from the CMRR test. Note also that either or both inputs can be driven to the absolute maximum limit (0.3V

beyond either supply rail) without damage or false output inversion.

Note 2: The input-referred trip points are the extremities of the differential input voltage required to make the comparator output

change state. The difference between the upper and lower trip points is equal to the width of the input-referred hysteresis
zone (see Figure 1).

Note 3: V

OS

is defined as the center of the input-referred hysteresis zone (see Figure 1).

Note 4: The polarity of I

B

reverses direction as VCMapproaches either supply rail. See Typical Operating Characteristics for more

detail.

Note 5: Specified over the full common-mode range (V

CMR

).

Note 6: Applies to the MAX941 only when in shutdown mode. Specification is for current flowing into or out of the output pin for

V

OUT

driven to any voltage from V+ to GND.

Note 7: Typical power dissipation specified with V+ = 3V; maximum with V+ = 6V.
Note 8: Parameter is guaranteed by design and specified with V

OD

= 5mV and C

LOAD

= 15pF in parallel with 400µA of sink or

source current. V

OS

is added to the overdrive voltage for low values of overdrive (see Figure 2).

Note 9: Specified between any two channels in the MAX942/MAX944.
Note 10: Specified as the difference between t

PD+

and t

PD-

for any one comparator.

Note 11: Applies to the MAX941 only for both –S—H—D—N–and–L—A—T—C—H–pins.
Note 12: Applies to the MAX941 only. Comparator is active with –L—A—T—C—H–pin driven high and is latched with –L—A—T—C—H–pin driven low

(see Figure 2).

Note 13: Applicable to the MAX941 only. Comparator is active with –S—H—D—N–pin driven high and is in shutdown with –S—H—D—N–pin driven

low. Shutdown disable time is the delay when –S—H—D—N–is driven high to the time the output is valid.

Note 14: The MAX941EUA and MAX942EUA are 100% production tested at T

A

= +25°C. Specifications over temperature are

guaranteed by design.

PARAMETER

SYMBOL CONDITIONS MIN TYP MAX UNITS

Supply Current per Comparator

380 600

Logic Input Voltage High V

IH

(Note 11) –

V

–2–+– + 0.4 –V–2–+– V

Logic Input Voltage Low V

IL

(Note 11) –

V

–2–+––

V

–2–+– - 0.4 V

Logic Input Current IIL, I

IHVLOGIC

= 0 or V+ (Note 11) 210µA

Data-to-Latch Setup Time t

S

(Note 12) 20 ns

Latch-to-Data Hold Time t

H

(Note 12) 30 ns

Latch Pulse Width t

LPW

MAX941 only 50 ns

Latch Propagation Delay t

LPD

MAX941 only 70 ns

Shutdown Time (Note 13) 3 µs

Shutdown Disable Time (Note 13) 10 µs

Propagation Delay Skew (Note 10) 10 ns

I

CC

V+ = 3V

350 500

MAX941 only, shutdown mode (V+ = 3V) 12 60

µA

1.0 4.2

Power Dissipation per
Comparator

PD (Note 7)

1.0 3.6

mW

Differential Propagation Delay dt

PD

(Note 9) 10 ns

MAX941

MAX942/MAX944

430 700MAX941

V+ = 5V

400 600MAX942/MAX944

MAX941

MAX942/MAX944

MAX94_C

MAX94_E

80 150

Propagation Delay

t

PD+

,

t

PD-

(Note 8)

80 200

ns

MAX941/MAX942/MAX944

High-Speed, Low-Power, 3V/5V, Rail-to-Rail,
Single-Supply Comparators

4 _______________________________________________________________________________________

__________________________________________Typical Operating Characteristics

(V+ = 3.0V, TA = +25°C, unless otherwise noted.)

100

40

0 100

PROPAGATION DELAY vs.

INPUT OVERDRIVE

50

90

MAX941-01

INPUT OVERDRIVE (mV)

PROPAGATION DELAY (ns)

75

70

60

25 50

80

30

t

PD+

t

PD-

RS = 10Ω
C

LOAD

= 15pF

400

100

10 100k

PROPAGATION DELAY vs.

SOURCE IMPEDANCE

150

350

MAX941-02

SOURCE IMPEDANCE (Ω)

PROPAGATION DELAY (ns)

10k

250

200

100 1k

300

50

t

PD+

t

PD-

C

LOAD

= 15pF

V

OD

= 5mV

180

60

0

PROPAGATION DELAY vs.

CAPACITIVE LOAD

80

160

MAX941-03

CAPACITIVE LOAD (pF)

PROPAGATION DELAY (ns)

400

120

100

100 300 500

140

200

RS = 10Ω
V

OD

= 5mV

t

PD+

t

PD-

130

-60 -20 40 80

PROPAGATION DELAY vs.

TEMPERATURE

70

110

MAX941-04

TEMPERATURE (°C)

PROPAGATION DELAY (ns)

060

90

120

60

100

80

-40 20 100 120

140

RS = 10Ω
C

LOAD

= 15pF

V

OD

= 5mV

0

1

OUTPUT LOW VOLTAGE

vs. SINK CURRENT

MAX941-07

SINK CURRENT (µA)

V

OL

(V)

0.1

0.2

0.3

0.4

0.5

10 100 1000 10,000

TA = -55°C

TA = +25°C

TA = +125°C

100

40

26

PROPAGATION DELAY vs.

SUPPLY VOLTAGE

50

90

MAX941-05

SUPPLY VOLTAGE (V)

PROPAGATION DELAY (ns)

5

70

60

34

80

30

t

PD+

t

PD-

RS = 10Ω
C

LOAD

= 15pF

V

OD

= 5mV

2.6

1 10,000

OUTPUT HIGH VOLTAGE vs.

SOURCE CURRENT

2.7

MAX941-06

SOURCE CURRENT (µA)

V

OH

(V)

1000

2.9

2.8

10 100

3.0

2.5

TA = +125°C

TA = +25°C

TA = -55°C

MAX941 TOTAL SUPPLY CURRENT

vs. SUPPLY VOLTAGE

SUPPLY CURRENT (µA)

0

2

SUPPLY VOLTAGE (V)

100

200

300

400

500

600

34 5 6

MAX941-08

TA = +125°C

TA = +25°C

TA = -55°C

MAX942 TOTAL SUPPLY CURRENT

vs. SUPPLY VOLTAGE

SUPPLY CURRENT (µA)

300

SUPPLY VOLTAGE (V)

400

500

600

700

800

MAX941-09

TA = +125°C

TA = +25°C

TA = -55°C

23456