ATA5756_08 Datasheet, PDF (1/20 Pages) ATMEL Corporation – UHF ASK/FSK Transmitter

Features
• PLL Transmitter IC with Single-ended Output
• High Output Power (6 dBm) at 8.1 mA (315 MHz) and 8.5 mA (433 MHz) Typical Values
• Divide by 24 (ATA5756) and 32 (ATA5757) Blocks for 13 MHz Crystal Frequencies and
for Low XTO Start-up Times
• Modulation Scheme ASK/FSK with Internal FSK Switch
• Up to 20 kBaud Manchester Coding, Up to 40 kBaud NRZ Coding
• Power-down Idle and Power-up Modes to Adjust Corresponding Current Consumption
through ASK/FSK/Enable Input Pins
• ENABLE Input for Parallel Usage of Controlling Pins in a 3-wire Bus System
• CLK Output Switches ON if the Crystal Current Amplitude has Reached 35% to 80% of
its Final Value
• Crystal Oscillator Time Until CLK Output is Activated, Typically 0.6 ms
• Supply Voltage 2.0 V to 3.6 V in Operation Temperature Range of -40°C to +125°C
• ESD Protection at all Pins (4 kV HBM)
• Small Package TSSOP10
Benefits
• Low Parasitic FSK Switch Integrated
• Very Short and Reproducible Time to Transmit Typically < 0.85 ms
• 13.125 MHz/13.56 MHz Crystals Give Opportunity for Small Package Sizes
UHF ASK/FSK
Transmitter
ATA5756
ATA5757
1. Description
The ATA5756/ATA5757 is a PLL transmitter IC which has been developed for the
demands of RF low-cost transmission systems at data rates up to 20 kBaud Man-
chester coding and 40 kBaud NRZ coding. The transmitting frequency range is
313 MHz to 317 MHz (ATA5756) and 432 MHz to 448 MHz (ATA5757), respectively.
It can be used in both FSK and ASK systems. Due to its shorten crystal oscillator set-
tling time it is well suited for Tire Pressure Monitoring (TPM) and for Passive Entry Go
applications.
Figure 1-1. System Block Diagram
1 Li cell
Encoder
Keys ^ATARx9x
UHF ASK/FSK
TPM and Remote control
transmitter
ATA5756/
ATA5757
PLL
UHF ASK/FSK
Remote control receiver
U3741B/
U3745B/
T5743/
T5744/
Demod.
Control
XTO
VCO
Antenna Antenna
IF Amp
PLL
XTO
1...3
µC
Power
amp.
LNA
VCO
4702J–RKE–09/08