MAXIM MAX9644, MAX9645, MAX9646 User Manual

General Description

The MAX9644/MAX9645/MAX9646 are small, single com­parators, ideal for a wide variety of portable electronics
applications such as cell phones, media players, and
notebooks that have extremely tight board space and
power constraints. These comparators are offered in both
a miniature 4-bump UCSP™ package with a 1mm x 1mm
footprint (as small as two 0402 resistors) and a
5-pin SOT23 package.

The ICs feature an input voltage range of -0.3V to
+5.5V, independent of supply voltage. These devices
maintain high impedance at the inputs even when pow­ered down (V

CC

or V

REF

= 0V). They also feature inter-

nal filtering to provide high RF immunity.

The ICs have an internal 0.2V reference. These devices
feature either a push-pull or an open-drain output. They
consume only 700nA (max) supply current and operate
down to V

CC

= 1V over the extended -40°C to +85°C tem-

perature range.

Applications

Cell Phones

Portable Media Players

Electronic Toys

Notebook Computers

Portable Medical Devices

Features

o Tiny, 1mm x 1mm x 0.6mm 4-Bump UCSP

Footprint = Two 0402 Resistors
Also Available in a 5-Pin SOT23 Package

o Ultra-Low Operating Current (700nA max)

o -0.3V to +5.5V Input Voltage Range

o Internal 0.2V Reference Trimmed to 1% Accuracy

o 15µs Propagation Delay

o -40°C to +85°C Extended Temperature Range

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision

Reference in 4-Bump UCSP

________________________________________________________________

Maxim Integrated Products

1

19-5803; Rev 1; 10/11

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.

EVALUATION KIT

AVAILABLE

Ordering Information

PART PIN-PACKAGE TOP MARK

MAX9644EBS+G45 4 UCSP +AGL

MAX9644EUK+ 5 SOT23 +AFJN

MAX9645EBS+G45 4 UCSP +AGM

MAX9645EUK+ 5 SOT23 +AFJO

MAX9646EBS+G45 4 UCSP +AGN

MAX9646EUK+ 5 SOT23 +AFJP

Note: All devices are specified over the extended -40°C to
+85°C operating temperature range.

+

Denotes a lead(Pb)-free/RoHS-compliant package.

G45

= Protective die coating.

UCSP is a trademark of Maxim Integrated Products, Inc.

Selector Guide

PART REFERENCE VOLTAGE (V) INPUT OUTPUT

MAX9644 0.2 Noninverting Open drain

MAX9645 0.2 Inverting Open drain

MAX9646 0.2 Noninverting Push-pull

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision
Reference in 4-Bump UCSP

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC= 3.3V, R

PULLUP

= 10kΩ to V

PULLUP

= 3.3V for MAX9644/MAX9645, TA= -40°C to +85°C. Typical values at TA= +25°C, unless

otherwise noted.) (Note 1)

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.

VCC, REF, IN to GND................................................-0.3V to +6V

OUT to GND (MAX9644/MAX9645)..........................-0.3V to +6V

OUT to GND (MAX9646 only) .................-0.3V to + (V

CC

+ 0.3V)

Output Short-Circuit Current Duration ....................................10s

Input Current into Any Terminal........................................±20mA

Continuous Power Dissipation

4-Bump UCSP (derate 3.0mW/°C above +70°C) .......238 mW

5-Pin SOT23 (derate 3.9mW/°C above +70°C)...........312 mW

Operating Temperature Range ...........................-40°C to +85°C

Junction Temperature......................................................+150°C

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

Bump Temperature (soldering) Reflow............................+235°C

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

Soldering Temperature (reflow) .......................................+260°C

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

DC CHARACTERISTICS

Input Voltage Range V

Input Bias Current I

Input Leakage Current I

Output Voltage Low V

Output Voltage High
(MAX9464 Only)

Output Leakage Current
(MAX9644/MAX9645 Only)

AC CHARACTERISTICS

Propagation Delay t

Fall Time t

Rise Time t

REFERENCE VOLTAGE

Input Threshold (Note 4) V

Input Threshold Error
(Note 4)

Input Threshold Hysteresis V

REF Tempco V

Power-Supply Rejection
Ratio

I

OUT_LEAKAGE

Delta-V

REF_TEMPCO

IN

IN

IN_SHDN

OL

V

OH

PD

F

R

REF

REF

HYS

PSRR V

Guaranteed by IIN test -0.3 +5.5 V

VIN = 0.2V to 5.5V (Note 2) 0.06 15 nA

VCC = 0, VIN = 5.5V (Note 2) < 0.1 15 nA

I

= 50µA, VCC = 1.0V 0.03 0.2

SINK

I

= 200µA, VCC = 1.2V 0.08 0.20

SINK

I

= 500µA, VCC = 1.8V 0.13 0.23

SINK

I

= 0.75mA, VCC = 3.3V 0.14 0.3

SINK

I

= 1.2mA, VCC = 5.5V 0.19 0.5

SINK

I

I

I

I

I

OUT = high, V

= 15µA, VCC = 1.0V V

SOURCE

= 40µA, VCC = 1.2V V

SOURCE

= 180µA, VCC = 1.8V V

SOURCE

= 0.3mA, VCC = 3.3V V

SOURCE

= 0.75mA, VCC = 5.5V V

SOURCE

PULLUP

(Note 2)

V

OVERDRIVE

= ±100mV (Note 3) 15 µs

CL = 10pF 14 ns

CL = 10pF, MAX9646 only 30 ns

MAX964_EBS+ 200

MAX964_EUK+ 199

TA = +25°C -1 +1

TA = -40°C to +85°C -3.5 +3.5

TA = -40°C to +85°C (Note 5) ±0.9 mV

(Note 6) 6 µV/°C

= 1.0V to 5.5V 40 53 dB

CC

= 5.5V

- 0.08V V

C C

- 0.08V V

C C

- 0.15V V

C C

- 0.13V V

C C

- 0.24V V

C C

< 0.1 15 nA

C C

- 0.20V

C C

- 0.23V

C C

C C

C C

- 0.2V

- 0.3V

- 0.5V

V

V

mV

%

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision

Reference in 4-Bump UCSP

_______________________________________________________________________________________ 3

Note 1: All devices are 100% production tested at TA = +25°C. Temperature limits are guaranteed by design.
Note 2: Too small to be measured in an ATE test environment. Only gross test to catch failures is implemented.
Note 3: Overdrive is defined as the voltage above or below the switching points.
Note 4: Guaranteed by ATE and/or bench characterization over temperature. V

REF

is the average of the trip points.

Note 5: Hysteresis is half the input voltage difference between the two switching points.
Note 6: Includes reference error along with comparator offset voltage error.

ELECTRICAL CHARACTERISTICS

(VCC= 3.3V, R

PULLUP

= 10kΩ to V

PULLUP

= 3.3V for MAX9644/MAX9645, TA= -40°C to +85°C. Typical values at TA= +25°C, unless

otherwise noted.) (Note 1)

Typical Operating Characteristics

(VCC= 3.3V, V

REF

= 1.8V, R

PULLUP

= 10kΩ to V

PULLUP

= 3.3V for MAX9644/MAX9645, GND = 0, TA= +25°C, unless otherwise noted.)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

POWER SUPPLY

Supply Voltage V

Supply Current I

Power-Up Time t

CC

CC

ON

Guaranteed by VOL/VOH tests 1.0 5.5 V

VCC = 1.0V 0.4 0.7

VCC = 5.5V 0.6 1.1

3ms

1000

800

600

400

SUPPLY CURRENT (nA)

200

0

06

SUPPLY CURRENT

vs. SUPPLY VOLTAGE

+85°C

+25°C

-40°C

SUPPLY VOLTAGE (V)

MAX9644 toc01

54321

vs. OUTPUT TRANSITION FREQUENCY

SUPPLY CURRENT

100

VCC = 5V

10

SUPPLY CURRENT (µA)

1

0.1 100

VCC = 3.3V

VCC = 1.8V

110

OUTPUT TRANSITION FREQUENCY (kHz)

1.0

0.9

MAX9644 toc02

0.8

0.7

0.6

0.5

0.4

0.3

OUTPUT VOLTAGE LOW (V)

0.2

0.1

0

OUTPUT VOLTAGE LOW

vs. SINK CURRENT

V

= 3.3V

REF

V

= 1.8V

REF

048

SINK CURRENT (mA)

µA

MAX9644 toc03

V

= 5V

REF

62

REFERENCE VOLTAGE

vs. TEMPERATURE

MAX9644 toc11

TEMPERATURE (°C)

REFERENCE VOLTAGE (mV)

201.6

202.0

201.8

201.4

201.2

201.0

201.7

201.9

201.5

201.3

201.1

-40 8510 60-15 35

VCC = 3.3V

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision
Reference in 4-Bump UCSP

4 _______________________________________________________________________________________

Typical Operating Characteristics

(VCC= 3.3V, V

REF

= 1.8V, R

PULLUP

= 10kΩ to V

PULLUP

= 3.3V for MAX9644/MAX9645, GND = 0, TA= +25°C, unless otherwise noted.)

OUTPUT VOLTAGE HIGH

vs. SOURCE CURRENT (MAX9646)

1.0

0.9

, V)

OH

0.8

- V

0.7

CC

0.6

0.5

0.4

0.3

0.2

OIUTPUT VOLTAGE HIGH (V

0.1

0

VCC = 1.8V

01.51.0 2.5 3.00.5 2.0
SOURCE CURRENT (mA)

VCC = 5V

VCC = 3.3V

MAX9644 toc04

-10

INPUT BIAS CURRENT (nA)

-15

-20

201.0

200.8

200.6

200.4

200.2

200.0

199.8

199.6

REFERENCE VOLTAGE (mV)

199.4

199.2

199.0

INPUT BIAS CURRENT

vs. INPUT BIAS VOLTAGE

5

0

-5

0 0.20 0.25 0.300.05 0.10 0.15

INPUT BIAS VOLTAGE (V)

REFERENCE VOLTAGE
vs. SUPPLY VOLTAGE

1.0 5.02.5 3.0 4.54.01.5 2.0 3.5
SUPPLY VOLTAGE (V)

MAX9644 toc05

VCC = 3.3V

MAX9644 toc07

17

16

15

14

13

12

PROPAGATION DELAY (µs)

11

10

9

-40 -15 60 853510

PROPAGATION DELAY

vs. TEMPERATURE

VOD = ±100mV

VCC = 3.3V

TEMPERATURE (°C)

VCC = 1.8V

VCC = 5V

MAX9644 toc08

PROPAGATION DELAY (µs)

80

70

60

50

40

30

20

10

0

PROPAGATION DELAY

vs. INPUT OVERDRIVE

VCC = 1.8V

VCC = 3.3V

0 100 150 25020050

INPUT OVERDRIVE (mV)

MAX9644 toc09

VCC = 5V

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision

Reference in 4-Bump UCSP

_______________________________________________________________________________________ 5

Typical Operating Characteristics (continued)

(VCC= 3.3V, V

REF

= 1.8V, R

PULLUP

= 10kΩ to V

PULLUP

= 3.3V for MAX9644/MAX9645, GND = 0, TA= +25°C, unless otherwise noted.)

REFERENCE VOLTAGE

vs. TEMPERATURE

MAX9644 toc11

REFERENCE VOLTAGE (mV)

201.6

202.0

201.8

201.4

201.2

201.0

201.7

201.9

201.5

201.3

201.1

-40 8510 60-15 35

VCC = 3.3V

POWER-SUPPLY REJECTION

FOR NO FALSE TRIGGERING

MAX9644 toc14

FREQUENCY (Hz)

TRIP POINT (mV)

100k100

200

206

194

202

196

204

198

10 10k1k 1M

VCC = 3.3V + 100mV

P-P

UPPER TRIP POINT

LOWER TRIP POINT

OUTPUT RESPONSE TO

SUPPLY VOLTAGE TRANSIENT

MAX9644 toc13

1ms/div

0V

0V

0V

3V

3.2V

V

CC

200mV/div

OUT
2V/div

OUT
2V/div

OUT
2V/div

VIN = VTH + 20mV

VIN = VTH + 10mV

VIN = VTH + 1mV

PROPAGATION DELAY AT VCC = 3.3V

0.3V

0.1V

0V

100µs/div

POWER-UP/POWER-DOWN RESPONSE

VIN = 0.3V

= 3.3V

V

CC

MAX9644 toc10

IN+
100mV/div

OUT
2V/div

MAX9644 toc12

0V

0V

V

CC

2V/div

OUT
2V/div

1ms/div

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision
Reference in 4-Bump UCSP

6 _______________________________________________________________________________________

Pin Description

Pin Configuration

TOP VIEW (BUMPS ON BOTTOM)

+

V

OUT

1

A1

A2

CC

5

OUT

MAX9644
MAX9645

V

CC

PIN

UCSP SOT23

A1 5 OUT

A2 4 IN

B1 1 V

B2 2, 3 GND Ground

NAME FUNCTION

CC

MAX9646

B1 B2INGND

UCSP SOT23

Comparator Output. The MAX9644/MAX9645 have open-drain outputs. The MAX9646 has a
push-pull output.

Comparator Input. The MAX9644/MAX9646 have noninverting inputs. The MAX9645 has
inverting inputs.

Power-Supply Voltage. Bypass to ground with a 0.1µF bypass capacitor.

GND

GND

MAX9644

2

MAX9645
MAX9646

3

4

IN

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision

Reference in 4-Bump UCSP

_______________________________________________________________________________________ 7

Detailed Description

The MAX9644/MAX9645/MAX9646 are extremely small
comparators ideal for compact, low-current, and low­voltage applications.

The ICs consume only 400nA (typ). The low-voltage
operating capability of the operating current makes
these devices extremely attractive to long-life battery­operated devices—these applications can now use a
single digital power-supply rail to power the new gener­ation of microcontrollers (which can be down to 0.9V).
All parts are available in a tiny 4-bump UCSP, which is
only 0.6mm tall and occupies a 1mm x 1mm footprint
and a 5-pin SOT23.

Input Stage Circuitry

Noninverting inputs are available on the MAX9644/
MAX9646 and inverting inputs are available on the
MAX9645.

The MAX9644/MAX9645/MAX9646 incorporate an inno­vative input stage architecture that allows their input
voltage to exceed VCCby several volts (limited only by
the

Absolute Maximum Ratings

). This is unlike tradition­al comparators that have an input ESD diode clamp
between the input and VCC, limiting this maximum over­voltage to about 0.3V. The ICs architecture maintains a
high input impedance to input signals even when the
device power-supply voltage is completely turned off
(VCCor REF taken to 0V). This greatly benefits flexible
power-saving schemes to be easily implemented in
advanced battery-operated devices. On-chip filtering
provides immunity from any RF noise being picked up by
input traces. These devices feature an internal tempera­ture-compensated, low-power 0.2V reference voltage.

Output Stage Structure

The MAX9644/MAX9645 have open-drain outputs that
allow them to interface to logic circuitry running from
supply voltages other than the one supplied to the part.
These devices require an external pullup resistor or
current source for proper operation. Many microcon­troller digital inputs ports can be readily programmed to
include these.

The MAX9646 has a push-pull output stage that can
both sink and source current, eliminating the need for
an external pullup resistor. In this case, the MAX9646
uses the microcontroller’s power supply as VCC.

Applications Information

Bypassing REF/V

CC

Place a 0.1µF capacitor between REF or VCCand
GND as close as possible to the device. During a
switching event, all comparators draw a current spike
from their power-supply rails. This current spike is
minimized by the use of an internal break-before-make
design.

Hysteresis Operation

The ICs feature internal hysteresis for noise immunity
and glitch-free operation. If additional hysteresis is
needed, an external positive feedback network can be
easily implemented on the MAX9644 and MAX9646 non­inverting input devices. Additional external hysteresis is
not possible on the MAX9645 because the noninverting
input of the comparator is not externally accessible.

Table 1. How Devices Behave Under Various Input Voltage Conditions

PART INPUT VOLTAGE CONDITIONS ACTION AT OUTPUT

MAX9644

MAX9645

MAX9646

VIN > 0.2V External pullup resistor pulls output high.

V

< 0.2V Output asserts low.

IN

VIN > 0.2V Output asserts low.

V

< 0.2V External pullup resistor pulls output high.

IN

VIN > 0.2V Output asserts high.

< 0.2V Output asserts low.

V

IN

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision
Reference in 4-Bump UCSP

8 _______________________________________________________________________________________

Typical Operating Circuits

Chip Information

PROCESS: BiCMOS

VCC = 1.0V TO 5.5V

0.2V REF

IN

MAX9644

V

DD

I/OOUT

MICROCONTROLLER

0.2V REF

IN

INTERNAL

PULLUP

IN

VCC = 1.0V TO 5.5V

MAX9646

0.2V REF

I/OOUT

VCC = 1.0V TO 5.5V

MAX9645

V

DD

MICROCONTROLLER

V

DD

INTERNAL

PULLUP

I/OOUT

MICROCONTROLLER

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision

Reference in 4-Bump UCSP

_______________________________________________________________________________________ 9

Package Information

For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or
“-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing per­tains to the package regardless of RoHS status.

PACKAGE TYPE PACKAGE CODE DOCUMENT NO. LAND PATTERN NO.

4 UCSP B4+1 21-0117 Refer to Application Note 1891

5 SOT23 U5+2 21-0057 90-0174

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision
Reference in 4-Bump UCSP

10 ______________________________________________________________________________________

Package Information (continued)

For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or
“-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing per­tains to the package regardless of RoHS status.

MAX9644/MAX9645/MAX9646

Low-Power Comparators with Precision

Reference in 4-Bump UCSP

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.

Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________

11

© 2011 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.

Revision History

REVISION

NUMBER

0 3/11 Initial release —

1 10/11 Updated Features section 1

REVISION

DATE

DESCRIPTION

PAGES

CHANGED