Difference between revisions of "Zappy Module"

From Hackstrich
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== Overview ==
 
== Overview ==
* Control input options could be:
+
* Main control input via I2C
** GPIO-based, simple "zap now" input (or a couple separate inputs that you can set with different options)
+
* ARM signal must be high before zapping is allowed
** I2C/SPI/RS232
+
* Two trigger pin inputs, can program levels for each via I2C then zap with simple "pull pin high" I/O
*** Could be used for instant control or programming levels/durations for later GPIO-based activation
 
  
 
== Theory of Operation ==
 
== Theory of Operation ==
 
* Input voltage from 3-9V is stepped up to 10V using a boost converter (AZ34063U) to get the intermediary voltage rail
 
* Input voltage from 3-9V is stepped up to 10V using a boost converter (AZ34063U) to get the intermediary voltage rail
** Or if 12V input is required, maybe use 14V or something as the intermediary voltage rail?
 
 
* MCU controls a FET that charges a cap from that rail via a series resistor to control charge rate
 
* MCU controls a FET that charges a cap from that rail via a series resistor to control charge rate
 
** Divider on the cap feeds into an analog pin on the MCU, once the analog pin reaches the desired level the MCU shuts the FET off again
 
** Divider on the cap feeds into an analog pin on the MCU, once the analog pin reaches the desired level the MCU shuts the FET off again

Revision as of 03:21, 9 March 2015

Zappy Module is a board-level module that takes control input via some kind of protocol and outputs signals to zap someone like shock collars do.

Project Status

  • 2015-03-08: Finished schematic and BOM, checklisted.
  • 2015-03-07: Started putting schematic and BOM together.
  • 2015-02-02: Started putting together overall circuit idea.
  • 2015-02-01: SPICEd out some ideas.
  • 2015-01-29: Captured waveforms of all output levels.
  • 2015-01-05: Arranged to borrow a shock collar to characterize the output of it.
  • 2013-05: Started throwing ideas around.

Overview

  • Main control input via I2C
  • ARM signal must be high before zapping is allowed
  • Two trigger pin inputs, can program levels for each via I2C then zap with simple "pull pin high" I/O

Theory of Operation

  • Input voltage from 3-9V is stepped up to 10V using a boost converter (AZ34063U) to get the intermediary voltage rail
  • MCU controls a FET that charges a cap from that rail via a series resistor to control charge rate
    • Divider on the cap feeds into an analog pin on the MCU, once the analog pin reaches the desired level the MCU shuts the FET off again
  • Once cap is charged, MCU pulses a FET that dumps the charge on the cap through a 1:100 (or so) transformer and to the output
    • 0.1-1kV should be achievable via timing the charge FET
  • May need a dump resistor if the cap is charged and needs to be discharged without zapping?
    • Could use the series charging resistor w/ a different FET to dump the cap through it?
    • Don't think this will be required, the charge cycle will only take ~1mS so it will be done right before the trigger, so the cap will never remain charged for long

Collar Reversing Waveforms

  • All collar output waveforms are through a 1/3 divider, so multiply by 3 to get actual amplitude
  • Lowest level (1L) seems to be ~90Vpp, highest seems to be ~450Vpp
    • I thought the highest was ~2x that? Need to measure the higher ones again to double check