The table shown in

Figure 3 summarizes the rise in die tem-

perature of the LM62 without any loading, and the thermal

resistance for different conditions.

2.0 Capacitive Loads

The LM62 handles capacitive loading well. Without any spe-

cial precautions, the LM62 can drive any capacitive load as

shown in

Figure 4. Over the specified temperature range the

LM62 has a maximum output impedance of 4.7 k

Ω.Inanex-

tremely 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

ply 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 4.7 k

Ω maximum

output impedance will form a 34 Hz lowpass filter. Since the

thermal time constant of the LM62 is much slower than the

30 ms time constant formed by the RC, the overall response

time of the LM62 will not be significantly affected. For much

larger capacitors this additional time lag will increase the

overall response time of the LM62.

SOT-23

SOT-23

no heat sink

small heat fin

(Note 13)

(Note 12)

θ

JA

T

θ

JA

T

(˚C/W)

(˚C)

(˚C/W)

(˚C)

Still air

450

0.17

260

0.1

Moving

air

180

0.07

part attached as shown in

Figure 2 .

Note 13: Part soldered to 30 gauge wire.

FIGURE 3. Temperature Rise of LM62 Due to

Self-Heating and Thermal Resistance (

θ

DS100893-15

FIGURE 4. LM62 No Decoupling Required for

Capacitive Load

DS100893-16

FIGURE 5. LM62 with Filter for Noisy Environment

DS100893-17

FIGURE 6. Simplified Schematic

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