LM131A Datasheet | National Semiconductor

Description The LM131 LM231 LM331 family of voltage-to-frequency converters are ideally suited for use in simple low-cost circuits for analog-to-digital conversion precision frequencyto-voltage conversion long-term integration linear frequency modulation or demodulation and many other functions The output when used as a voltage-to-frequency converter is a pulse train at a frequency precisely proportional to the applied input voltage Thus it provides all the inherent advantages of the voltage-to-frequency conversion techniques and is easy to apply in all standard voltage-to-frequency converter applications Further the LM131A LM231A LM331A attains a new high level of accuracy versus temperature which could only be attained with expensive voltage-to-frequency modules Additionally the LM131 is ideally suited for use in digital systems at low power supply voltages and can provide low-cost analog-to-digital conversion in microprocessor-controlled systems And the frequency from a battery powered voltage-to-frequency converter can be easily channeled through a simple photoisolator to provide isolation against high mon mode levels The LM131 LM231 LM331 utilizes a new temperaturepensated band-gap reference circuit to provide excellent accuracy over the full operating temperature range at power supplies as low as 4 0V The precision timer circuit has low bias currents without degrading the quick response necessary for 100 k Hz voltage-to-frequency conversion And the output is capable of driving 3 TTL loads or a high voltage output up to 40V yet is short-circuit-proof against VCC Features Y Y Y Y Y Y Guaranteed linearity 0 01% max Improved performance in existing voltage-to-frequency conversion applications Split or single supply operation Operates on single 5V supply Pulse output patible with all logic forms Excellent temperature stability g 50 ppm C max Low power dissipation 15 m W typical at 5V Wide dynamic range 100 d B min at 10 k Hz full scale frequency Wide range...