General Description
The TDK 5111 is a single chip ASK/FSK transmitter for the frequency band 314-317 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. The IC can be used for both ASK and FSK modulation.

FEATUREs
■ fully integrated frequency synthesizer
■ VCO without external components
■ high efficiency power amplifier typically 10 dBm @ 3 V
■ frequency range 314-317 MHz
■ ASK/FSK modulation
■ low supply current typ. 13 mA@3V
■ voltage supply range 2.1 - 4 V
■ power down mode
■ low voltage sensor
■ programmable divided clock output for µC
■ low external component count

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