TDA7100 Datasheet, PDF (10/41 Pages) Infineon Technologies AG – 434 MHz ASK/FSK Transmitter in 10-pin Package

TDA7100
Functional Description
Pin Symbol
No.
7 FSKDTA
Interface Schematic
V_S
+1.2 V
60 kΩ
7
90 kΩ
Function
Digital frequency modulation can
be imparted to the Xtal Oscillator
by this pin. The VCO-frequency
varies in accordance to the
frequency of the reference
+1.1 V oscillator.
A logic high (FSKDTA > 1.5V or
30 µA _{open) sets the FSK switch to a}
high impedance state.
A logic low (FSKDTA < 0.5 V)
closes the FSK switch from
FSKOUT (pin 4) to GND (pin 3).
A capacitor can be switched to the
reference crystal network this way.
The Xtal Oscillator frequency will
be shifted giving the designed FSK
frequency deviation.
Data Sheet
10
V 1.0, 2007-05-02