125KHz wake-up receiver and 433MHz data transmitter for battery-less TPMS

A 125 KHz wake-up receiver to receive wake-up signal and a 433MHz data transmitter to transmit temperature and pressure data of the tire to central control module for battery-less TPMS (Tire Pressure Monitoring System) are presented in this paper. The receiver adopts dual-channel to improve reliability and logarithmic amplifier to achieve ASK demodulation and dynamic range compression. The receiver is implemented in 0.35μm BCD process. Maximum data rate is 35Kbps with 0.5mVpp sensitivity and 5μA typical power consumption. The transmitter is implemented in 0.18μm process. The typical power consumption is 7.3mA with a transmit power of -10 dBm@433.9 MHz, and phase noise of the PLL is - 103dBc/Hz@ 300 KHz with 30Kbps data rate.

1. Introduction

In recent years, TPMS has become an essential safety system in vehicles. Block diagram of the battery-less TPMS is shown in Figure 1. The wireless communication modules are shown in black dashed box, and this paper mainly focuses on the red parts. Figure 1.

Block diagram of the battery-less TPMS