Datasheet

LMV7235, LMV7239
SNOS532M –SEPTEMBER 2000–REVISED FEBRUARY 2013 www.ti.com
CRYSTAL OSCILLATOR
A simple crystal oscillator using the LMV7239 is shown below. Resistors R1 and R2 set the bias point at the
comparator's non-inverting input. Resistors R3, R4 and C1 sets the inverting input node at an appropriate DC
average level based on the output. The crystal's path provides resonant positive feedback and stable oscillation
occurs. The output duty cycle for this circuit is roughly 50%, but it is affected by resistor tolerances and to a
lesser extent by the comparator offset.
Figure 22. Crystal Oscillator
IR RECEIVER
The LMV7239 is an ideal candidate to be used as an infrared receiver. The infrared photo diode creates a
current relative to the amount of infrared light present. The current creates a voltage across R
D
. When this
voltage level cross the voltage applied by the voltage divider to the inverting input, the output transitions.
Figure 23. IR Receiver
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