While ago there was a short talk in the EzUHF help thread about conversion of the EzUHF RSSI/Link Quality output into an analog voltage to feed an OSD different than the EzOSD.
I made small and simple circuit to convert the PPM signal from the EzUHF RX into an analog voltage:
The circuit uses an AVR microcontroller to read the PPM signal and an simple R2R digital-analog converter to create a proportional voltage.
An LMV358 rail-to-rail opamp is used to buffer the output voltage.
Mainly intended to convert the RSSI signal to analog, the circuit can be used for other purposes as well where you want to convert a PPM signal to analog.
The LMV358 is able to source/sink at least 50mA so a LED can be driven directly for example.
The PPM signal is considered valid between 800-2200us, where below 1000us gives 0V and above 2000us gives 5V.
Since an rail-to-rail opamp is used a full voltage swing between 0-5V can be archived.
Short video to demonstrate the funcitonality:
Firmware for PPM to analog converter