General Description
The TDA 5100A is a single chip ASK transmitter for the frequency band 433-435 MHz. The IC offers a high level of integration and needs only a few external components. The device contains a fully integrated PLL synthesizer and a high efficiency power amplifier to drive a loop antenna. A special circuit design and an unique power amplifier design are used to save current consumption and therefore to save battery life. Additionally features like a power down mode, a low power detect and a divided clock output are implemented.

Features
■ fully integrated frequency synthesizer
■ VCO without external components
■ high efficiency power amplifier
■ frequency range 433-435 MHz
■ ASK modulation
■ low supply current (typically 7mA)
■ voltage supply range 2.1 - 4 V
■ power down mode
■ low voltage sensor
■ clock output for µC
■ low external component count

Applications
■ Keyless entry systems
■ Remote control systems
■ Alarm systems
■ Communication systems