Texas Instruments Incorporated
Oscillator for pulse communication with reduced startup latency

Abstract:

An oscillator for use in pulse communication of pulse signals with a startup latency and a pulse oscillation signal (such as for use in a transmitter for OOK pulse communication with pulse modulation). The oscillator includes an LC resonator having a tank impedance, and including a high-side node (Vp), and a low-side node Vn, and having a tank voltage corresponding to [Vp-Vn]. A pulse startup circuit, includes a PMOS transistor with a source connected to a supply voltage VDD, and a drain connected through a resistance R to the Vp node (where R is significantly larger than the tank impedance), and connected to an attenuation capacitance, in parallel with the resistance R. The PMOS control terminal is coupled to receive a kick start pulse to initiate a pulse signal. the oscillator can include high-side and low-side pulse startup circuits.