4.0 V

The LM56 V

ing well. Without any special precautions, these outputs can

drive any capacitive load as shown in Figure 4 .

5.0 NOISY ENVIRONMENTS

Over the specified temperature range the LM56 V

put has a maximum output impedance of 1500

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 4 . In a noisy environment

it may be necessary to add a capacitor from the V

TEMP

output to ground. A 1 µF output capacitor with the 1500

Ω

output impedance will form a 106 Hz lowpass filter. Since the

thermal time constant of the V

than the 9.4 ms time constant formed by the RC, the overall

response time of the V

affected. For much larger capacitors this additional time lag

will increase the overall response time of the LM56.

6.0 APPLICATIONS CIRCUITS

The circuit shown in Figure 5 will reduce the effective bias

current error for V

equivalent to the error term of V

of the bias current on the first trip point can be defined by the

following equations:

where I

Similarly, bias current affect on V

01289319

FIGURE 4. Loading of V

01289320

FIGURE 5. Reducing Errors Caused by Bias Current

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