Atmel Corporation

Mark Bossard

John L Fagan

Daniel Scott Cohen

A programmable pulse generator having a clock signal delay chain, multiplexer, and reduced voltage charge circuit. The clock delay chain comprises a plurality of propagated delays, coupled to the multiplexer. The multiplexer selects a particular clock delay signal from a plurality of delay chain taps. The multiplexer is driven by a tap select register coupled to a state machine. The state machine controls the programmable pulse output, encoding the data by varying the pulse width and delay between pulses. The delay of pulse outputs from the multiplexer are reduced by coupling a reduced voltage pre-charge circuit to the multiplexer.

Selectable delay pulse generator

An electronic device selects one of a plurality of input signals for coupling to an output channel. Individual pulldowns provide a separate pathway for each input, and are coupled to a common node which: is pre-charged to a voltage less than a system voltage. Each pulldown is coupled to a select line for gating an associated input signal.

Reduced voltage pre-charge multiplexer

A vernier time shifting circuit is used for fine-tuning capture of a clock signal and/or a data signal to compensate for fluctuations produced by the system or other variations within non-time invariant parts of the chip. Other variations can include process, temperature, or voltage differences. The vernier sample time shifting circuit allows shifting the signal in small steps to allow for optimal sampling.

Vernier circuit for fine control of sample time

An electronic device selects one of a plurality of input signals for coupling to an output channel. Individual pulldowns provide a separate pathway for each input, and are coupled to a common node which is pre-charged to a voltage less than a system voltage. Each pulldown is coupled to a select line for gating an associated input signal.

An dual phase pulse modulation (DPPM) encoder circuit converts data into a series of high and low signal pulses, each of whose time durations or pulse widths represents a group of M data bits, with the alternating high and low pulses representing successive groups. The encoder circuit may include a set of parallel-in, serial-out shift registers that subdivide received data words into the M-bit groups, a state machine that specified the pulse durations for each received group, e.g., by incrementing a state that indicates selected signal pulse transition times, a system clock delay chain with multiple taps, a multiplexer controlled by the state machine for successively selecting different taps, and a toggle flip-flop that is clocked by the multiplexer output.

Growing community of inventors

Upper Marlboro, MD, United States of America

Mark Bossard