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TH72035 Datasheet, PDF (1/20 Pages) Melexis Microelectronic Systems – 868/915MHz FSK/ASK Transmitter
TH72035
868/915MHz
FSK/ASK Transmitter
Features
! Fully integrated PLL-stabilized VCO
! Frequency range from 850 MHz to 930 MHz
! Single-ended RF output
! FSK through crystal pulling allows modulation
from DC to 40 kbit/s
! High FSK deviation possible for wideband data
transmission
! ASK achieved by on/off keying of internal
power amplifier up to 40 kbit/s
! Wide power supply range from 1.95 V to 5.5 V
! Very low standby current
! On-chip low voltage detector
! High over-all frequency accuracy
! FSK deviation and center frequency
independently adjustable
! Adjustable output power range from
-11 dBm to +9.5 dBm
! Adjustable current consumption from
5.1 mA to 13.4 mA
! Conforms to EN 300 220 and similar standards
! 10-pin Quad Flat No-Lead Package (QFN)
Ordering Information
Part Number
Temperature Code
TH72035
K (-40 °C to 125 °C)
Package Code
LD (10L QFN 3x3 Dual)
Delivery Form
120 pc/tray
5000 pc/T&R
Application Examples
! General digital data transmission
! Tire Pressure Monitoring Systems (TPMS)
! Remote Keyless Entry (RKE)
! Wireless access control
! Alarm and security systems
! Garage door openers
! Remote Controls
! Home and building automation
! Low-power telemetry systems
Pin Description
ASKDTA
FSKDTA
FSKSW
ROI
ENTX
top
TH72035
VCC
VEE
OUT
VEE
PSEL
bottom
10
1
9
2
8
3
7
4
6
5
General Description
The TH72035 FSK/ASK transmitter IC is designed for applications in the European 868 MHz industrial-
scientific-medical (ISM) band, according to the EN 300 220 telecommunications standard. It can also be
used for any other system with carrier frequencies ranging from 850 MHz to 930 MHz (e.g. for applications in
the US 902 to 928 MHz ISM band).
The transmitter's carrier frequency fc is determined by the frequency of the reference crystal fref. The inte-
grated PLL synthesizer ensures that each RF value, ranging from 850 MHz to 930 MHz, can be achieved.
This is done by using a crystal with a reference frequency according to: fref = fc/N, where N = 32 is the PLL
feedback divider ratio.
39010 72035
Rev. 008
Page 1 of 20
Data Sheet
June/07