This pulse generator is designed to provide precise timing signals with flexible pulse width options. Powered by two input voltages of 5V and 3.3V, it generates a single pulse triggered on the rising edge of the TRIG pin. The pulse amplitude is dependent on the load, offering 1.65V into a 50-ohm load or 3.3V in a high-impedance (Hi-Z) load.

The pulse width is programmable and can be selected from four options, each equally spaced by a standard width, ensuring versatility for a range of applications. There are two variants of the board available to accommodate different needs: a 5 ns variant, and a 10 ns variant, providing pulse widths as low as 5 ns or 10 ns, respectively.

This pulse generator is ideal for testing, signal processing, and other applications requiring high-speed, precise pulse generation.

Features

Operates off 5 V, and 3.3 V supply rails
- Note: Both rails are required for proper functionality
Pulse amplitude is 1.65 V into 50 ohm or 3.3 V into Hi-Z
Four selectable pulse widths:
- 5 ns, 10 ns, 15 ns, and 20 for the 5 ns variant
- 10 ns, 20 ns, 30 ns, and 40 for the 10 ns variant
MMCX output connector
On-board TRIG buffer to relax input rise-time requirements

Use Cases

Time Domain Reflectometry (TDR)
Ultra-Wideband (UWB) Radar
Optical driver

Specifications

Absolute Maximum

Parameter	Min	Max	Unit
5V	-0.5	6.5	V
3V3	-0.5	4.6	V
TRIG	0	25	MHz

Recommended Operation

Parameter	Min	Typ.	Max	Unit
5V	4.8	5.0	5.2	V
3V3	3.2	3.3	3.4	V
VIH (2)	2.4	—	3.4	V
VIL (2)	0.0	—	0.8	V
VOH HI-Z 50	2.2 1.1	—	3V3 3V3/2	V
VOL HI-Z 50	0.0 0.0	—	0.56 0.28	V

All parts are rated for -40 to 85 °C
Specification applies to EN_L, S0, S1, TRIG, and HOLD

Operation

The pulse generator functions by comparing a reference signal to a delayed signal. The resulting waveform is a narrow pulse of just a few nanoseconds.

EN_L	S0	S1	HOLD	OUT
0	0	0	0	3x PW
0	0	1	0	4x PW
0	1	0	0	1x PW
0	1	1	0	2x PW
0	X	X	1	1
1	X	X	Y	Y

A single pulse is triggered on the rising edge of the TRIG pin. The pulse width is selected based on the table above. The pulse amplitude is dependent on the load, offering 1.65V into a 50-ohm load or 3.3V in a high-impedance (Hi-Z) load.

Recommended Footprint

Use 120 mil x 120 mil pads for each pin
All un-labeled pins must be connected to GND
It is recommended to have copper cutout on the mounting surface to avoid potential short-circuits from vias. The boards are spec’d to have their vias tented, but accidental exposure can happen. This is a pre-cautionary step.

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