NSC LM74CIBP-5, LM74-3EVAL, LM74CIBP-3 Datasheet

LM74
SPI/MICROWIRE

™

12-Bit Plus Sign Temperature Sensor

General Description

The LM74 is a temperature sensor, Delta-Sigma analog-to­digital converter with an SPI and MICROWIRE compatible
interface. The host can query the LM74 at any time to read
temperature. A shutdown mode decreases power consump­tion to less than 10 µA. This mode is useful in systems where
low average power consumption is critical.

The LM74 has 12-bit plus sign temperature resolution
(0.0625˚C per LSB) while operating over a temperature
range of −55˚C to +150˚C.

The LM74’s 3.0V to 5.5V supply voltage range, low supply
current and simple SPI interface make it ideal for a wide
range of applications. These include thermal management
and protection applications in hard disk drives, printers, elec­tronic test equipment, and office electronics. The LM74 is
available in the SO-8 package as well as an 5-Bump micro
SMD package.

Applications

n System Thermal Management
n Personal Computers
n Disk Drives
n Office Electronics

n Electronic Test Equipment

Features

n 0.0625˚C temperature resolution.
n Shutdown mode conserves power between temperature

reading

n SPI and MICROWIRE Bus interface
n 5-Bump micro SMD package saves space

Key Specifications

j

Supply Voltage 3.0V or 2.65V to

5.5V

j

Supply Current operating 265µA (typ)

520µA (max)

shutdown 3µA (typ)

j

Temperature

Accuracy −10˚C to 65˚C

±

1.25˚C(max)

−25˚C to 110˚C

±

2.1˚C(max)

−55˚C to 125˚C

±

3˚C(max)

Simplified Block Diagram

10090901

MICROWIRE®is a registered trademark of National Semiconductor Corporation.
TRI-STATE

®

is a registered trademark of National Semiconductor Corporation.

April 2003

LM74 SPI/MICROWIRE 12-Bit Plus Sign Temperature Sensor

© 2003 National Semiconductor Corporation DS100909 www.national.com

Connection Diagrams

SO-8 5-Bump micro SMD

10090902

TOP VIEW

NS Package Number M08A

10090924

Note:

- Pin numbers are referenced to the package marking text orientation. Pin

1 is designated by the square.

- Reference JEDEC Registration MO-211, variation BC

- The top 4 characters designate the date code. The bottom 3 characters

designate the device type (see ordering information).

TOP VIEW

NS Package Number BPD05MPB

Ordering Information

Order Number

Package

Marking

NS Package

Number

Supply Voltage Transport Media

LM74CIM-3 LM74CIM-3 SO-8, M08A 3.0V to 3.6V 95 Units in Rail

LM74CIMX-3 LM74CIM-3 SO-8, M08A 3.0V to 3.6V 2500 Units in Tape and Reel

LM74CIM-5 LM74CIM-5 SO-8, M08A 4.5V to 5.5V 95 Units in Rail

LM74CIMX-5 LM74CIM-5 SO-8, M08A 4.5V to 5.5V 2500 Units in Tape and Reel

LM74CIBP-3 T8 micro SMD,

BPD05MPB

2.65V to 3.6V 250 Units in Tape and Reel

LM74CIBPX-3 T8 micro SMD,

BPD05MPB

2.65V to 3.6V 3000 Units in Tape and Reel

LM74CIBP-5 T9 micro SMD,

BPD05MPB

4.5V to 5.5V 250 Units in Tape and Reel

LM74CIBPX-5 T9 micro SMD,

BPD05MPB

4.5V to 5.5V 3000 Units in Tape and Reel

LM74

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Pin Descriptions

Label SO-8

Pin

#

micro

SMD

Pin

#

Function Typical Connection

SI/O 1 1 Slave Input/Output - Serial bus bi-directional data

line. Schmitt trigger input.

From and to Controller

SC 2 5 Slave Clock - Serial bus clock Schmitt trigger input

line.

From Controller

NC 3 No Connection No Connection

GND 4 4 Power Supply Ground Ground

NC 5 No Connection No Connection

NC 6 No Connection No Connection

CS

7 3 Chip Select input. From Controller

V

+

8 2 Positive Supply Voltage Input DC Voltage from 3.0V to 5.5V for the

LM74CIM and 2.65V to 5.5V for the
LM74CIBP. Bypass with a 0.1 µF ceramic
capacitor.

Typical Application

10090903

FIGURE 1. COP Microcontroller Interface

LM74

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Absolute Maximum Ratings (Note 1)

Supply Voltage −0.3V to 6.0V

Voltage at any Pin −0.3V to V

+

+ 0.3V

Input Current at any Pin (Note 2) 5 mA

Package Input Current (Note 2) 20 mA

Storage Temperature −65˚C to +150˚C

Soldering Information, Lead Temperature

SO-8 Package (Note 3)

Vapor Phase (60 seconds)
Infrared (15 seconds)

215˚C
220˚C

ESD Susceptibility (Note 4)

Human Body Mode

LM74CIBP SC, pin 5 1900V

LM74CIM and LM74CIBP all

other pins

2000V

Machine Model 200V

Operating Ratings

Specified Temperature Range T

MIN

to T

MAX

(Note 5)
LM74CIBP
LM74CIM

−40˚C to +125˚C

−55˚C to +150˚C

Supply Voltage Range (+V

S

)

LM74CIBP +2.65V to +5.5V

LM74CIM +3.0V to +5.5V

Temperature-to-Digital Converter Characteristics

Unless otherwise noted, these specifications apply for V+= 2.65V to 3.6V for the LM74CIBP -3, V+= 3.0V to 3.6V for the
LM74CIM -3 and V

+

= 4.5V to 5.5V for the LM74 -5 (Note 6). Boldface limits apply for TA=TJ=T

MIN

to T

MAX

; all other lim-

its T

A=TJ

=+25˚C, unless otherwise noted.

Parameter Conditions

Typical

(Note 7)

LM74-5

Limits

(Note 8)

LM74-3

Limits

(Note 8)

Units

(Limit)

Temperature Error (Note 6) T

A

= −10˚C to +65˚C

±

1.25

±

1.25 ˚C (max)

T

A

= −25˚C to +110˚C

±

2.1 +2.65/−2.15 ˚C (max)

T

A

= −40˚C to +85˚C +2.65/−1.65

±

2.15 ˚C (max)

T

A

= −40˚C to +110˚C +2.65/

−2.0

+2.65/−2.15 ˚C (max)

T

A

= −55˚C to +125˚C

±

3.0

±

3.5 ˚C (max)

T

A

= −55˚C to +150˚C

±

5.0

±

5.0 ˚C (max)

Resolution 13 Bits

Temperature
Conversion Time

SO-8 (Note 9) 280 425 425 ms (max)

micro SMD (Note 9) 611 925 925 ms (max)

Quiescent Current SO-8 Serial Bus Inactive 310 520 520 µA (max)

micro SMD 265 470 470 µA (max)

SO-8 Serial Bus Active 310 µA

micro SMD 310 µA

SO-8 Shutdown Mode,

V

+

= 3.3V

7µA

micro SMD 3 µA

SO-8 Shutdown Mode,

V

+

=5V

8µA

micro SMD 4 µA

Logic Electrical Characteristics

DIGITAL DC CHARACTERISTICS Unless otherwise noted, these specifications apply for V+= 2.65V to 3.6V for the

LM74CIBP -3, V

+

= 3.0V to 3.6V for the LM74CIM -3 and V+= 4.5V to 5.5V for the LM74 -5 (Note 6). Boldface limits apply

for T

A=TJ=TMIN

to T

MAX

; all other limits TA=TJ=+25˚C, unless otherwise noted.

Symbol Parameter Conditions

Typical

(Note 7)

Limits

(Note 8)

Units

(Limit)

V

IN(1)

Logical “1” Input Voltage V+x 0.7 V (min)

V

+

+ 0.3 V (max)

V

IN(0)

Logical “0” Input Voltage −0.3 V (min)

V

+

x 0.3 V (max)

Input Hysteresis Voltage V

+

= 3.0V to 3.6V 0.8 0.35 V (min)

V

+

= 4.5V to 5.5V 0.8 0.33 V (min)

I

IN(1)

Logical “1” Input Current VIN=V

+

0.005 3.0 µA (max)

LM74

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Logic Electrical Characteristics (Continued)

DIGITAL DC CHARACTERISTICS Unless otherwise noted, these specifications apply for V+= 2.65V to 3.6V for the

LM74CIBP -3, V

+

= 3.0V to 3.6V for the LM74CIM -3 and V+= 4.5V to 5.5V for the LM74 -5 (Note 6). Boldface limits apply

for T

A=TJ=TMIN

to T

MAX

; all other limits TA=TJ=+25˚C, unless otherwise noted.

Symbol Parameter Conditions

Typical

(Note 7)

Limits

(Note 8)

Units

(Limit)

I

IN(0)

Logical “0” Input Current VIN= 0V −0.005 −3.0 µA (min)

C

IN

All Digital Inputs 20 pF

V

OH

High Level Output Voltage IOH= −400 µA 2.4 V (min)

V

OL

Low Level Output Voltage IOL=+2mA 0.4 V (max)

I

O_TRI-STATE

TRI-STATE Output Leakage
Current

VO= GND
V

O

=V

+

−1
+1

µA (min)

µA

(max)

SERIAL BUS DIGITAL SWITCHING CHARACTERISTICS Unless otherwise noted, these specifications apply for V+= 2.65V
to 3.6V for the LM74CIBP -3, V

+

= 3.0V to 3.6V for the LM74CIM -3 and V+= 4.5V to 5.5V for the LM74 -5 (Note 6); CL(load

capacitance) on output lines = 100 pF unless otherwise specified. Boldface limits apply for T

A=TJ=TMIN

to T

MAX

; all other

limits T

A=TJ

= +25˚C, unless otherwise noted.

Symbol Parameter Conditions

Typical

(Note 7)

Limits

(Note 8)

Units

(Limit)

t

1

SC (Clock) Period 0.16

DC

µs (min)

(max)

t

2

CS Low to SC (Clock) High Set-Up Time 100 ns (min)

t

3

CS Low to Data Out (SO) Delay 70 ns (max)

t

4

SC (Clock) Low to Data Out (SO) Delay 100 ns (max)

t

5

CS High to Data Out (SO) TRI-STATE 200 ns (max)

t

6

SC (Clock) High to Data In (SI) Hold Time 50 ns (min)

t

7

Data In (SI) Set-Up Time to SC (Clock) High 30 ns (min)

10090904

FIGURE 2. Data Output Timing Diagram

LM74

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