555 Makes Handy Voltage to time Converter:  02/01/01 EDN-Design Ideas / (Schematic / circuit added 10/05) The circuit in Figure 1 is a simple, low-cost voltage-to-time converter using the ubiquitous 555 timer chip. You can use the IC's monostable multivibrator as a voltage-to-time converter by connecting the analog-voltage input to the charging resistor, R, instead of connecting R to VCC. With this modification, the timer chip's output-timing cycle, tP, is proportional to the input voltage, VIN. When you apply an input voltage, the voltage across capacitor C charges exponentially according to the formula VC=VIN(1–et/RC), where RC is the time constant of the circuit, with C in farads and R in ohms. During one time constant, the voltage across the capacitor changes by approximately 63% of VIN. The output timing of the monostable multivibrator is tP=1.1 RC. By keeping RC constant with fixed R and C values and varying the input voltage, VIN, you obtain variable output timing. The output pulse width in this circuit is inversely proportional to the input voltage....

AN-279: Using the AD650 Voltage-to-Frequency Converter as a Frequency-to-Voltage Converter:  AN-279 - Analog Devices Application Notes  (Circuit / schematic design added 6/06)

AN795: Voltage-To-Frequency/Frequency-To-Voltage Converter:  Microchip Application Note - Published 12-Nov-02   (added 2/06)

Circuit Converts Pulse Width to Voltage #2:  10/28/99 EDN-Design Ideas / (Electronic Schematic / circuit added 4/02) -- The circuit is optimized for a positive-going pulse width of1 to2 msec, repeating at intervals of approximately17 msec. The output produces a voltage of0.95V for a1-msec pulse to2.25V for a2-msec pulse.

Circuit Converts Pulse Width to Voltage:  10/25/01 EDN Design Ideas  /  (added 1/05)  The circuit in Figure 1 converts pulse information to a clean dc voltage by the end of a single incoming pulse. In another technique, an RC filter can convert a PWM signal to an averaged dc voltage, but this method is slow in responding. Converting low-duty-cycle pulse information is slower yet. ...

DDS IC Plus Frequency to Voltage Converter Make Low Cost Dac:  02/05/04 EDN Design Ideas  /  (added 1/05)  Precision DACs are essential in many consumer, industrial, and military applications, but high-resolution DACs can be costly. Frequency-to-voltage converters have good nonlinearity specifications—typically, 0.002% for the AD650—and are inherently monotonic. This Design Idea shows how you can use a frequency-to-voltage converter and a DDS (direct-digital-synthesizer) chip for precise......

F/V Converter has High Accuracy:  05/12/94 EDN Design Ideas /  (added 2/06)

Frequency to Voltage Converter uses Sample and Hold to Improve Response and Ripple:  National Semiconductor Application Notes,28-Jun-1996 (circuit added 7/02)

Frequency-to-Voltage Converter uses Sample-and-Hold to Improve Response and Ripple:  National Semiconductor - Application Note   (Circuit / schematic design added 6/06)

Hear Amateurs on Your FM Radio!:  (added 2/05)

LM2907 Tachometer/Speed Switch Building Block Applications:  National Semiconductor Application Note 04-Nov-1995 (circuit added 7/02)

Monostable Makes Low Cost F/ Volt Converter:  02/18/99 EDN-Design Ideas / (Circuit / schematic design added 6/06) The circuit in Figure 1 is a low-cost frequency-to-voltage (F/V) converter. Using a monostable (one-shot) multivibrator, the circuit accepts an open-collector square wave that varies in frequency from 0 to 10 kHz. The one-shot produces a pulse of a fixed width each time the input signal triggers it. The result is a variable-frequency, variable-duty-cycle signal at the output of the one-shot. The time constant determined by R2C1, 100 µsec, determines the width of the pulses the one-shot produces. This time matches the period of the maximum input frequency (10 kHz). The duty cycle of the one-shot's output is thus 100% when the input is at its maximum frequency....

New Phase Locked Loops:  (Electronic Schematic / circuit added 4/02)

Precision Voltage-To-Frequency Converter:  AN-C: Application Note CV/F Converter ICs Handle Frequency-to-Voltage Needs,  3-Oct-02  (added 2/06)

Using the AD650 Voltage-to-Frequency Converter as a Frequency-to-Voltage Converter:  AN-279 - Analog Devices Application Notes  (Circuit / schematic design added 6/06)

Voltage-To-Frequency/Frequency-To-Voltage Converter:  Microchip Application Note - Published 12-Nov-02   (added 2/06)