Datasheet
Package Availability, Models, Samples & Pricing
General Description
The LM231/LM331 family of voltage-to-frequency converters are ideally suited for use in simple low-cost circuits for analog-to-digital conversion, precision frequency-to-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 LM231A/LM331A attain a new high level of accuracy versus temperature which could only be attained with expensive voltage-to-frequency modules. Additionally the LM231/331 are 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 photo isolator to provide isolation against high common mode levels.
The LM231/LM331 utilize a new temperature-compensated 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 kHz voltage-to-frequency conversion. And the output are capable of driving 3 TTL loads, or a high voltage output up to 40V, yet is short-circuit-proof against VCC.
Reliability Metrics
| Part Number |
Process |
EFR Reject |
EFR Sample Size |
PPM |
LTA Rejects |
LTA Device Hours |
FITS |
MTTF (Hours) |
|
LM331AN | SLM | 0 | 44046 | 0 | 0 | 3532500 | 1 | 1002356520
|
|
LM331N | SLM | 0 | 44046 | 0 | 0 | 3532500 | 1 | 1002356520
|
Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR.
The Long Term Failure Rates were calculated
at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress
temperature of 150°C to an application temperature of 55°C.
For more information on Reliability Metrics, please click here.
Application Notes
| Title | Size in Kbytes |
Date |
 |
| AN-210: Application Note 210 New Phase-Locked-Loops Have Advantages as Frequency to Voltage Converters (and more) |
339
Kbytes |
3-Oct-02 |
Download |
| AN-240: Application Note 240 Wide-Range Current-to-Frequency Converters |
126
Kbytes |
3-Oct-02 |
Download |
| AN-285: Application Note 285 An Acoustic Transformer Powered Super‐High Isolation Amplifier |
172
Kbytes |
4-Oct-04 |
Download |
| AN-C: Application Note C V/F Converter ICs Handle Frequency-to-Voltage Needs |
187
Kbytes |
3-Oct-02 |
Download |
| AN-673: 2-Way Multiplexed LCD Drive and Low Cost A/D-Converter Using V/F Techniques with COP8 Microcontrollers |
526
Kbytes |
5-Aug-95 |
Download |
| AN-265: Application Note 265 An Electronic Watt-Watt-Hour Meter |
185
Kbytes |
3-Oct-02 |
Download |
| AN-D: Application Note D Versatile Monolithic V/Fs can Compute as Well as Convert with High Accuracy |
248
Kbytes |
3-Oct-02 |
Download |
More Application Notes
| Title | Size in Kbytes |
Date |
|
| AN-74: Application Note 74 LM139/LM239/LM339 A Quad of Independently Functioning Comparators |
702
Kbytes |
1-Oct-02 |
Download |
| AN-225: Application Note 225 IC Temperature Sensor Provides Thermocouple Cold-Junction Compensation |
89
Kbytes |
2-Oct-02 |
Download |
| AN-298: Application Note 298 Isolation Techniques for Signal Conditioning |
379
Kbytes |
2-Oct-02 |
Download |
| AN-242: Application Note 242 Applying a New Precision Op Amp |
383
Kbytes |
4-Oct-04 |
Download |
| AN-295: Application Note 295 A High Performance Industrial Weighing System |
117
Kbytes |
4-Oct-04 |
Download |
| AN-286: Application Note 286 Applications of the LM392 Comparator Op Amp IC |
135
Kbytes |
2-Oct-02 |
Download |
| AN-311: Application Note 311 Theory and Applications of Logarithmic Amplifiers |
258
Kbytes |
2-Oct-02 |
Download |
| AN-272: Application Note 272 Op Amp Booster Designs |
382
Kbytes |
2-Oct-02 |
Download |
| AN-288: Application Note 288 System-Oriented DC-DC Conversion Techniques |
405
Kbytes |
3-Oct-02 |
Download |
| AN-275: Application Note 275 CMOS D/A Converters Match Most Microprocessors |
127
Kbytes |
2-May-04 |
Download |
| AN-247: Application Note 247 Using the ADC0808/ADC0809 8-Bit µP Compatible A/D Converters with 8-Channel Analog Multiplexer |
547
Kbytes |
3-Oct-02 |
Download |
| AN-256: Application Note 256 Circuitry for Inexpensive Relative Humidity Measurement |
119
Kbytes |
2-Oct-02 |
Download |
| AN-258: Application Note 258 Data Acquisition Using the ADC0816 and ADC0817 8-Bit A/D Converter with On-Chip 16 Channel Multiplexer |
683
Kbytes |
4-Oct-04 |
Download |
| AN-284: Application Note 284 Single-Supply Applications of CMOS MICRODACs |
121
Kbytes |
3-Oct-02 |
Download |
| AN-274: Application Note 274 CMOS A/D Converter Interfaces Easily with Many Microprocessors |
73
Kbytes |
3-Oct-02 |
Download |
| AN-301: Application Note 301 Signal Conditioning for Sophisticated Transducers |
579
Kbytes |
2-Oct-02 |
Download |
[Information as of 8-Nov-2009]
|
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