Delay Generator 4

Delay Generator can start from either external trigger-pulse «Trigger In» (using both rising or falling fronts), or from the internal generator with adjustable frequency.

Parameters of the output pulses «CH ٠ 1»÷«CH ٠ 4» are adjusted independently, using Windows-based software «DelayGenerator.exe».

Operational settings are saved in the flash memory of the generator, and they can also be recorded by the software. Additional output «Sync Out» (pulse through the channel «CH ٠ 1») is used for synchronization of the oscilloscope.

Supply of power and connection with personal computer is done by means of standard USB-cable with micro-USB connector.

This Delay Generator is intended to control E-O Q-switching modules (Pockels Cell) by means of producing synchro-pulses of an adjustable duration and distributing them over 4 channels at the pre-defined moments with resolution of 217 psec.

Technical Specifications of the Synchronization Module
Syncro-pulse «Trigger-In»

• • Triggering Mode ……………………………………………………………………………………………  external/internal
  • External Synchronization……………………………………………………… using both rising and falling edges
  • Pulse Repetition Rate …………………………………………………………………………………….  up 10 kHz
  • Pulse Voltage Amplitude (input impedance 50Ω) …………………………………………  5 V
  • Pulse Duration ……………………………………………………………………………………………….  ≥ 10 nsec
  • Delay between triggering and start of the timing count………………………………… 83 ÷ 95 nsec
  • Delay timing jitter ………………………………………………………………………………………….  7 nsec

Output channels «CH ٠ 1», «CH ٠ 2», «CH ٠ 3», «CH ٠ 4»

• • Number of the output channels……………………………………………………………………… 4
  • Pulse amplitude (with 50Ω  load) …………………………………………………………………..  5 ÷ 5.6 V
  • Duration of the rising/falling edges ………………………………………………………………  < 5 nsec
  • Adjustable pulse duration …………………………… Pulse1 ÷ Pulse4 ……………………..  7 nsec ÷ 10 µsec
  • Adjustable Delay1 ÷ Delay4 …………………………………………………………………………..  7 nsec ÷ 10 µsec
  • Adjustment discrete steps ……………………………………………………………………………..  0.217 nsec
  • Jitter between output channels ……………………………………………………………………..  0.5 nsec

Output Syncro-pulse «Sync Out»

• • Front of the pulse coincides with the rising of «CH ٠ 1»
  • Pulse Amplitude (with 50Ω load) ……………………………………………………………………  5 ÷ 5.6 V
  • Pulse Duration ………………………………………………………………………………………………..  10 µsec

General Parameters

• • Supply of Power ………………………………………………………………………………………………  5 V x 200 µА
  • Dimensions W×L×H ……………………………………………………………………………………….  140×110×40 mm

¹ See the pulse diagram below

Pulse Diagram for Synchronization Module «Delay Generator 4»

Distinctive Features of the Generator.

Generator is built on the basis of a microcontroller with clock-speed 144 MHz, therefore presence of the input trigger-pulse is determined within 7 nsec at the longest. After detection of the trigger-pulse, microcontroller starts high temporal resolution 217 psec timer (after approx. 90 nsec delay). Therefore, jitter between input trigger-pulse and beginning of the timing count can reach as much as 7 nsec.

Inside of the high-resolution timer jitter between output channels rarely exceeds 400 psec, though in some cases it may rise to 600 nsec. Magnitude of the jitter doesn’t really depend on the pulse duration and delays.

Minimal allowable duration of the pulse and delay (in software) is set at 7 nsec. These parameters should be set at not less than 8 nsec. Actual pulsewidth at the driver’s output is ~2 nsec shorter than setting.