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0 capacitive loads, Figure 5. lm60 with filter for noisy environment, 0 mounting – Rainbow Electronics LM60 User Manual

Page 6: Lm60

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1.0 Mounting

(Continued)

2.0 Capacitive Loads

The LM60 handles capacitive loading well. Without any spe-
cial precautions, the LM60 can drive any capacitive load as
shown in

Figure 4. Over the specified temperature range the

LM60 has a maximum output impedance of 800

. In an

extremely noisy environment it may be necessary to add
some filtering to minimize noise pickup. It is recommended
that 0.1 µF be added from +V

S

to GND to bypass the power

supply voltage, as shown in

Figure 5. In a noisy environment

it may be necessary to add a capacitor from the output to
ground. A 1 µF output capacitor with the 800

output imped-

ance will form a 199 Hz lowpass filter. Since the thermal time
constant of the LM60 is much slower than the 6.3 ms time
constant formed by the RC, the overall response time of the
LM60 will not be significantly affected. For much larger ca-
pacitors this additional time lag will increase the overall
response time of the LM60.

SOT-23

*

SOT-23

**

TO-92

*

TO-92

***

no heat sink

small heat fin

no heat fin

small heat fin

θ

JA

T

J

− T

A

θ

JA

T

J

− T

A

θ

JA

T

J

− T

A

θ

JA

T

J

− T

A

(˚C/W)

(˚C)

(˚C/W)

(˚C)

Still air

450

0.17

260

0.1

180

0.07

140

0.05

Moving air

180

0.07

90

0.034

70

0.026

*

-Part soldered to 30 gauge wire.

**

-Heat sink used is

1

2

" square printed circuit board with 2 oz. foil with part attached as shown in

Figure 2 .

***

-Part glued or leads soldered to 1” square of 1/16” printed circuit board with 2 oz. foil or similar.

FIGURE 3. Temperature Rise of LM60 Due to

Self-Heating and Thermal Resistance (

θ

JA

)

01268115

FIGURE 4. LM60 No Decoupling Required for

Capacitive Load

01268116

FIGURE 5. LM60 with Filter for Noisy Environment

LM60

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