General Description

The MAX6627/MAX6628 precise digital temperature

sensors report the temperature of a remote sensor. The

remote sensor is a diode-connected transistor, typically

a low-cost, easily mounted 2N3904 NPN type that

replaces conventional thermistors or thermocouples.

The MAX6627/MAX6628 can also measure the die tem-

perature of other ICs, such as microprocessors (µPs) or

microcontrollers (µCs) that contain an on-chip, diode-

connected transistor.

Remote accuracy is ±1°C when the temperature of the

remote diode is between 0°C and +125°C and the tem-

perature of the MAX6627/MAX6628 is +30°C. The tem-

perature is converted to a 12-bit + sign word with

0.0625°C resolution. The architecture of the device is

capable of interpreting data as high as +145°C from

the remote sensor. The MAX6627/MAX6628 tempera-

ture should never exceed +125°C.

These sensors are 3-wire serial interface SPI™ compat-

ible, allowing the MAX6627/MAX6628 to be readily con-

nected to a variety of µCs. The MAX6627/MAX6628 are

read-only devices, simplifying their use in systems

where only temperature data is required.

Two conversion rates are available, one that continu-

ously converts data every 0.5s (MAX6627), and one

that converts data every 8s (MAX6628). The slower ver-

sion provides minimal power consumption under all

operating conditions (30µA, typ). Either device can be

read at any time and provide the data from the last con-

version.

Both devices operate with supply voltages between

+3.0V and +5.5V, are specified between -55°C and

+125°C, and come in the space-saving 8-pin SOT23

package.

Applications

Hard Disk Drive

Smart Battery Packs

Automotive

Industrial Control Systems

Notebooks, PCs

Features

o Accuracy

±1°C (max) from 0°C

±2.4°C (max) from -55°C

0°C

o 12-Bit + Sign, 0.0625°C Resolution

o Low Power Consumption

30µA (typ) (MAX6628)

200µA (typ) (MAX6627)

o Operating Temperature Range (-55°C to +125°C)

o Measurement Temperature Range, Remote

Junction (-55°C to +145°C)

o 0.5s (MAX6627) or 8s (MAX6628) Conversion Rate

o SPI-Compatible Interface

o +3.0V to +5.5V Supply Range

o 8-Pin SOT23 Package

Remote ±1°C Accurate Digital Temperature

Sensors with SPI-Compatible Serial Interface

________________________________________________________________ Maxim Integrated Products

1

19-2032; Rev 1; 7/01

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.

Ordering Information

PART

TEMP. RANGE

PIN-

PACKAGE

TOP

MARK

MAX6627MKA-T

-55°C to +125°C

8 SOT23-8

AAEQ

MAX6628MKA-T

-55°C to +125°C

8 SOT23-8

AAER

SPI is a trademark of Motorola, Inc.

Pin Configuration appears at end of data sheet.

SDO

GND

SCK

µC

+ 3V TO + 5.5V

MAX6627

MAX6628

CS

DXP

DXN

2200pF

2200pF

0.1

µF

Typical Operating Circuit