TH72012

433MHz

ASK Transmitter

Page 7 of 21

REVISION 013 - JUNE 14, 2017

3901072012

2.7. Mode Control Logic

The mode control logic allows two different modes

of operation as listed in the following table. The

mode control pin ENTX is pulled-down internally.

This guarantees that the whole circuit is shut down

if this pin is left floating.

ENTX

Mode

Description

0

TX standby

TX disabled

1

TX active

TX enable

2.8. Timing Diagrams

transmitter start-up time. The crystal oscillator starts oscillation and the PLL locks to the desired output frequency

carrier can be ASK modulated.

Fig. 4: Timing diagram for ASK modulation

low

low

high

high

LOCK

ASKDTA

RF carrier

t

low

high

ENTX