LM231, LM331

SNOSBI2B – JUNE 1999 – REVISED MARCH 2013

www.ti.com

less than 10 mV peak, but the response will be slow, with a 0.1 second time constant, and settling of 0.7 second

to 0.1% accuracy.

In the precision circuit, an operational amplifier provides a buffered output and also acts as a 2-pole filter. The

ripple will be less than 5 mV peak for all frequencies above 1 kHz, and the response time will be much quicker

than in Figure 18. However, for input frequencies below 200 Hz, this circuit will have worse ripple than Figure 18.

The engineering of the filter time-constants to get adequate response and small enough ripple simply requires a

study of the compromises to be made. Inherently, V-to-F converter response can be fast, but F-to-V response

can not.

*Use stable components with low temperature coefficients.

See APPLICATIONS INFORMATION.

**This resistor can be 5 k

***Use low offset voltage and low offset current op-amps for A1: recommended types LF411A or LF356.

Figure 17. Precision Voltage-to-Frequency Converter,

100 kHz Full-Scale, ±0.03% Non-Linearity

*Use stable components with low temperature coefficients.

Figure 18. Simple Frequency-to-Voltage Converter,

10 kHz Full-Scale, ±0.06% Non-Linearity

10

Submit Documentation Feedback

Copyright © 1999–2013, Texas Instruments Incorporated

Product Folder Links: LM231 LM331