The KESTX01 is a single chip ASK (Amplitude Shift Key) transmitter IC. It is designed to operate in a variety of low power radio applications including keyless entry, general domestic and industrial remote control, RF tagging and local paging systems.
The KESTX01 is a single‑chip ASK (Amplitude Shift Key) transmitter IC designed for low‑power radio applications such as keyless entry, remote control, RF tagging and paging. It integrates a crystal reference oscillator, a frequency‑multiplying PLL and a power‑amplifier stage, operating around the 433.92 MHz band while emphasizing low quiescent current and a power‑down mode to extend battery life.
Key features include low supply current, adjustable output power via the PWRC pin, a fully integrated VCO, PLL and PA, and a balanced open‑collector output that can drive a PCB loop antenna directly. Electrical specifications cover supply voltage 3.5‑6.5 V, junction temperature –55 °C to +150 °C, and typical standby current of 0.7 µA. The device provides configurable output current and extinction ratio, and includes testability provisions for production testing.
| Supply voltage (VCC) | 3.5 V to 6.5 V |
|---|---|
| Junction temperature | -55 °C to +150 °C |
| Standby supply current (I_CC1) | 0.7 µA |
| Output current at IF150 (typical) | 3.8 mA pk‑pk |
| Extinction ratio | 40 dB |
| VCO operating frequency range | 400 MHz – 460 MHz |
| Phase detector gain | ≈8 µA/rad |
| PWRC bias voltage | 1.20 V (nominal) |
The integrated VCO operates from 400 MHz to 460 MHz, and the device is typically used at a final output of 433.92 MHz.
Output power is set by the bias current on the PWRC pin, which is controlled by an external resistor; the bias voltage is nominally 1.20 V.
The absolute maximum rating for any pin voltage is VEE‑0.5 V to VCC+0.5 V, with VEE allowed up to +8.0 V.
A crystal of 6.78 MHz is required to generate the 433.92 MHz output frequency.