PT2262 and pt2272M2

[Chuuut]

Hi,
i am using the pt2262 and pt2272M2 for my project.
1.The problems i am having now is, i do not know what the value of the resistor i should use to connect the oscillator pin-PIN15 and PIN16 for pt2262 and pt2272M2.
2.and the resistor at the pin 17 , is it have a direct relation to the resistor at the pin 15 and pin 16?
hopefully u guys can understand what i am trying to ask.
best regards
chuut

[ober]

not sure the correct value, anyway looking at the datasheet, most of sample circuit uses 4.7M Ohm. You should try that.

Opening my DIY house light remote control, it uses 315MHz RF, the SMD resistor between pin 15 and pin 16 is labeled as 475 = 4700000 = 4.7M.

For pin 17, not sure.

Anyway, hope this help.

[ABSF]

Hi,
i am using the pt2262 and pt2272M2 for my project.
1.The problems i am having now is, i do not know what the value of the resistor i should use to connect the oscillator pin-PIN15 and PIN16 for pt2262 and pt2272M2.
2.and the resistor at the pin 17 , is it have a direct relation to the resistor at the pin 15 and pin 16?
hopefully u guys can understand what i am trying to ask.
best regards
chuut

This is from the datasheet of PT2272

SINGLE RESISTOR OSCILLATOR
The built-in oscillator circuitry of PT2272 allows a precision oscillator to be constructed with only an
external resistor. For the PT2272 to decode correctly the waveform that was received, the oscillator
frequency of PT2272 must be 2.5~8 times that of the transmitting PT2262. It is a good practice to
center the PT2272 oscillator frequency in this window to gain best window margin at both sides. The
typical oscillator with various resistor values is shown below for both PT2262 and PT2272.

PT2262 p15/p16..... PT2272 p17/p18
1.5M ............................ 270K
3.3M ............................ 680K
4.7M ............................ 820K

HTH

Allen