R

(1)

1nF

TMP20

MSP430

C

(1)

TMP20

MSP430

Vset

Vref

VCC

VCC

VCC

-

+

Vout

Vtemp

Vtrip

R110k

TEMP

V2 5

GND

T

GND

VOUT

V+

2

4

5

TMP20

+

-

+

REF

U1 TLV3021

Analog Temperature Switch

V

trip

80C

=

Input voltage(V)

25.00

35.00

45.00

55.00

65.00

75.00

85.00

95.00

1

.00

05

1

.00

15

1

.00

25

0.00

1.25

2.50

3.75

5.00

TripPoin

80C

t =

TMP20

SBOS466 – DECEMBER 2009

www.ti.com

OUTPUT DRIVE and CAPACITIVE LOADS

TINA-TI

(FREE DOWNLOAD SOFTWARE)

When used in noisy environments, adding a capacitor

from the output to ground with a series resistor filters

Using TINA-TI SPICE-Based Analog Simulation

the TMP20 output; this configuration is illustrated in

Program with the TMP20

Figure 11. The TMP20 can directly drive up to 1nF of

TINA is a simple, powerful, and easy-to-use circuit

load capacitance while sourcing and sinking 600

μA.

simulation program based on a SPICE engine.

Under this condition, capacitive loads in the range of

TINA-TI is a free, fully functional version of the TINA

1nF to 10

μF require a 150Ω series output resistor to

software, preloaded with a library of macromodels in

achieve a stable temperature measurement. The

addition to a range of both passive and active

output impedance of the TMP20 is 10

Ω (typical)

models. It provides all the conventional dc, transient,

when sinking current and less than 1

Ω when sourcing

and frequency domain analysis of SPICE as well as

current, as shown in Figure 1.

additional design capabilities.

Available as a free download from the Analog eLab

Design

Center,

TINA-TI

offers

extensive

post-processing capability that allows users to format

results in a variety of ways.

Virtual instruments offer users the ability to select

input waveforms and probe circuit nodes, voltages,

and waveforms, creating a dynamic quick-start tool.

Figure 12 and Figure 13 show example TINA-TI

circuits for the TMP20 that can be used to develop,

modify, and assess the circuit design for specific

applications. Links to download these simulation files

are given below.

NOTE: These files require that either the TINA

(1) A series resistor, R, may be required depending upon the

software (from DesignSoft) or TINA-TI software be

amount of capacitance, C, and the amount of source/sink current

installed. Download the free TINA-TI software from

drawn from the output of the TMP20.

the TINA-TI folder.

Figure 11. TMP20 Output Filtering

Note:

The TMP20 TINA model is preliminary only.

Figure 12. Analog Temperature Switch

To download a compressed file that contains the TINA-TI simulation file for this circuit, click the following link:

Analog Temperature Switch.

8

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Copyright © 2009, Texas Instruments Incorporated

Product Folder Link(s): TMP20