Rainbow Electronics MAX6626 User Manual

General Description

The MAX6625/MAX6626 combine a temperature sensor,
a programmable overtemperature alarm, and an I2C™­compatible serial interface into single compact packages.
They convert their die temperatures into digital values
using internal analog-to-digital converters (ADCs). The
result of the conversion is held in a temperature register,
readable at any time through the serial interface. A dedi­cated alarm output, OT, activates if the conversion result
exceeds the value programmed in the high-temperature
register. A programmable fault queue sets the number of
faults that must occur before the alarm activates, prevent­ing spurious alarms in noisy environments. OT has pro­grammable output polarity and operating modes.

The MAX6625/MAX6626 feature a shutdown mode that
saves power by turning off everything but the power-on
reset and the I2C-compatible interface. Four separate
addresses can be configured with the ADD pin, allowing
up to four MAX6625/MAX6626 devices to be placed on
the same bus. The MAX6625P/MAX6626P OT outputs are
open drain, and the MAX6625R/MAX6626R OT outputs
include internal pullup resistors.

The MAX6625 has a 9-bit internal ADC and can function
as a replacement for the LM75 in most applications. The
MAX6626 has a 12-bit internal ADC. Both devices come
in the space-saving 6-pin SOT23 package.

Applications

Fan Control
Temperature Alarms
System Temperature Control
Industrial Equipment

Features

♦ 9-Bit Temperature-to-Digital Converter (MAX6625)

♦ 12-Bit Temperature-to-Digital Converter (MAX6626)

♦ Accuracy

±1°C (T

A

= +25°C)
±1.5°C (0°C to +50°C)
±2°C (0°C to +70°C)
±3°C (-40°C to +85°C)
±4°C (-55°C to +125°C)

♦ 133ms Conversion Time

♦ I

2

C-Compatible Serial Interface

♦ Up to Four Devices on a Single Bus

♦ Versatile Alarm Output with Programmable Trip

Temperature and Hysteresis

♦ Low-Power Shutdown Mode

♦ Space-Saving 6-Pin SOT23 Package

MAX6625/MAX6626

9-Bit/12-Bit Temperature Sensors with

I2C-Compatible Serial Interface in a SOT23

________________________________________________________________ Maxim Integrated Products 1

Pin Configuration

4

6

V

S

0.1µF

1

MAX6625
MAX6626

3

SCL

TO I

2

C

MASTER

10k
(OMIT FOR MAX6625R
AND MAX6626R)

SDA

52

1k

1k

OT OUTPUT

Typical Operating Circuit

19-1841; Rev 2; 7/02

*For device options, see Selector Guide at end of data sheet.

Requires special solder temperature profile described in the
Absolute Maximum Ratings section.

Ordering Information

I2C is a trademark of Philips Corp.

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.

PART TEMP. RANGE PIN-PACKAGE

M A X6 6 2 5 P M U T - T * -55°C to +125°C 6 SOT23-6

MAX6625RMUT-T* -55°C to +125°C 6 SOT23-6

M A X6 6 2 6 P M U T - T * -55°C to +125°C 6 SOT23-6

MAX6626RMUT-T* -55°C to +125°C 6 SOT23-6

TOP VIEW

SDA

GND

16V

MAX6625

2

MAX6626

34

SOT23-6

S

5 ADD

OTSCL

MAX6625/MAX6626

9-Bit/12-Bit Temperature Sensors with
I2C-Compatible Serial Interface in a SOT23

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(+3V ≤ VS≤ +5.5V, T

A =

-55°C to +125°C, unless otherwise noted.)

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.

VSto GND ................................................................-0.3V to +6V

OT, SCL, SDA to GND.............................................-0.3V to +6V

ADD to GND .................................................-0.3V to (V

S

+ 0.3V)

Current into Any Pin............................................................±5mA

OT Sink Current.................................................................. 20mA

Continuous Power Dissipation

6-Pin SOT23 (derate 9.1mW/°C above +70°C)............727mW

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

Storage Temperature Range .............................-60°C to +150°C

Lead Temperature .............................................................Note 1

ESD Rating (Human Body Model)......................................2000V

Note 1: This device is constructed using a unique set of packaging techniques that impose a limit on the thermal profile the device

can be exposed to during board-level solder attach and rework. This limit permits only the use of the solder profiles recom­mended in the industry-standard specification, IPC/JEDEC J-STD-020A, paragraph 7.6, Table 3 for IR/VPR and Convection
Reflow. Preheating is required. Hand or wave soldering is not allowed.

Power-Supply Voltage V

ADC Resolution

Temperature Resolution

Accuracy (Notes 2, 3)

Power-Supply Sensitivity VS = +3V to +5.5V 1 °C/V

Conversion Time t

OT Pullup Resistor R

OT Saturation Voltage (Note 4) V

OT Delay (Programmable through fault queue) 1 × t

T

HIGH

T

LOW

I2C-COMPATIBLE I/O: SCL, SDA, ADD

Input High Voltage V

Input Low Voltage V

Input Hysteresis 0.2 V

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Default Temperature T

Default Temperature T

S

I2C-compatible active 1 mA

I2C-compatible inactive 250 µAQuiescent Current I

C

Shutdown mode 1 µA

MAX6625 9

MAX6626 12

MAX6625 0.5

MAX6626 0.0625
TA = +25°C, VS = +3V to +3.6V ±1

0°C = TA ≤ +50°C, VS = +3.0V to +3.6V ±1.5

0°C = T

A

C

MAX6625R, MAX6626R only 25 50 kΩ

P

I

L

HIGH

LOW

IH

IL

= 4mA 0.8 V

OUT

VS < +3.6V 2

VS > +3.6V 3

≤ +70°C, VS = +3.0V to +3.6V ±2.0

3 5.5 V

133 ms

C

6 × t

C

80 °C

75 °C

0.8 V

Bits

°C/LSB

°C

ms

V

MAX6625/MAX6626

9-Bit/12-Bit Temperature Sensors with

I2C-Compatible Serial Interface in a SOT23

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(+3V ≤ VS≤ +5.5V, T

A =

-55°C to +125°C, unless otherwise noted.)

Note 2: Guaranteed by design and characterization to ±5 sigma.
Note 3: Quantization error not included in specifications for temperature accuracy.
Note 4: Output current should be minimized for best temperature accuracy. Power dissipation within the MAX6625/MAX6626 will

cause self-heating and temperature drift; see Thermal Considerations section.

Note 5: A master device must provide a hold time of at least 300ns for the SDA signal in order to bridge the undefined region of

SCL’s falling edge.

Note 6: C

B

= total capacitance of one bus line in pF. Tested with CB= 400pF.

Note 7: Input filters on SDA, SCL, and ADD suppress noise spikes less than 50ns.

Figure 1. Serial Bus Timing

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Input High Leakage Current I

Input Low Leakage Current I

Input Capacitance C

Output Low Voltage V

Output High Current I

I2C-COMPATIBLE TIMING

Serial Clock Frequency f

Bus Free Time Between STOP
and START Conditions

START Condition Hold Time t

STOP Condition Setup Time t

Clock Low Period t

Clock High Period t

Data Setup Time t

Data Hold Time (Note 5) t

Maximum Receive SCL/SDA
Rise Time (Note 6)

Minimum Receive SCL/SDA
Rise Time (Note 6)

Maximum Receive SCL/SDA
Fall Time (Note 6)

Minimum Receive SCL/SDA
Fall Time (Note 6)

Transmit SDA Fall Time
(Note 6)

Pulse Width of Suppressed
Spike (Note 7)

V

IH

IL

IN

OL

OH

SCL

t

BUF

HD:STA

SU:STO

LOW

HIGH

SU:DAT

HD:DAT

t

R

t

R

t

F

t

F

t

F

t

SP

= +5V ±1 µA

IN

V

= 0 ±1 µA

IN

I

= 3mA 0.4 V

OL

VOH = 5V 1 µA

CB = 400pF, IO = 3mA

10 pF

DC 400 kHz

1.3 µs

0.6 µs

0.6 µs

1.3 µs

0.6 µs

100 ns

0 0.9 µs

300 ns

20 +

0.1C

B

300 ns

20 +

0.1C

B

20 +

0.1C

B

250 ns

50 ns

ns

ns

SCL

SDA

t

HD:STA

t

F

t

LOW

t

SU:DAT

t

R

t

HIGH

t

HD:DAT

t

SU:STO

t

BUF

MAX6625/MAX6626

9-Bit/12-Bit Temperature Sensors with
I2C-Compatible Serial Interface in a SOT23

4 _______________________________________________________________________________________

Typical Operating Characteristics

(VS = +3.3V, TA = +25°C, unless otherwise noted.)

Pin Description

0

20

60

40

80

100

-5 50101520

RESPONSE TO THERMAL SHOCK

TEMPERATURE vs. TIME

MAX6625 toc01

TIME (s)

OUTPUT TEMPERATURE (°C)

DEVICE IMMERSED IN +85°C
FLUORINERT BATH

80

120

100

160

140

180

200

-55 5 35-25 65 95 125

STATIC QUIESCENT SUPPLY CURRENT

vs. TEMPERATURE

MAX6625 toc02

TEMPERATURE (°C)

INPUT CURRENT (µA)

80

120

100

160

140

180

200

-55 5 35-25 65 95 125

DYNAMIC QUIESCENT SUPPLY CURRENT

vs. TEMPERATURE

MAX6625 toc03

TEMPERATURE (°C)

INPUT CURRENT (µA)

-5

-2

-3

-4

0

-1

4

3

2

1

5

-50 -25 0 25 50 75 100 125

TEMPERATURE ERROR vs.

TEMPERATURE

MAX6625 toc04

TEMPERATURE (°C)

TEMPERATURE ERROR (°C)

MAXIMUM LIMIT

±5 SIGMA RANGE

MINIMUM LIMIT

PIN NAME FUNCTION

1 SDA I2C-Compatible Serial Bidirectional Data Line

2 GND Power-Supply Ground

3 SCL I2C-Compatible Clock Input

4 OT Temperature Alarm Output

5 ADD I2C-Compatible Address Set Pin: Ground (0), VS (1), SDA (2), SCL (3); see Table 1.

6VSPower-Supply Input, +3V to +5.5V. Bypass VS to GND with a 0.1µF capacitor.