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

Ω.Inan

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

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

Ω 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.

no heat sink

small heat fin

no heat fin

small heat fin

θ

JA

T

θ

JA

T

θ

JA

T

θ

JA

T

(˚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

Figure 2 .

FIGURE 3. Temperature Rise of LM60 Due to

Self-Heating and Thermal Resistance (

θ

01268115

FIGURE 4. LM60 No Decoupling Required for

Capacitive Load

01268116

FIGURE 5. LM60 with Filter for Noisy Environment

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