Parts list:

1 – Radio Shack proto type circuit board

2 – 555 timer 8 pin DIP chips

3 – 100 ohm resistors – R1, R5, R9

1 – 470 ohm resistor – R6

3 – 100 K ohm resistors – R2, R3, R7

1 – 10 ohm resistors – R8

1 – Meg ohm resistor – R4

1 – 47 mF capacitor – C1

1 – 22 mF capacitor – C7

3 – 0.1 mF ceramic disc capacitor – C2, C3, C6

1 – 1 mF Tantalum capacitor – C4

1 – 4.7 mF capacitor – C5

1 – 1N4002 diode D1

1 – 1N4742 12v Zener diode – D2

1 – Red LED 12v rated

1 – Green LED 12v rated

1 – N-Channel MOSFET transistor – Q1

Radio shack part #276-2072

1 – Momentary contact switch – SW3

2 – spdt switches – SW1, SW2

2 – Aligator clips

A few feet of double strand wire

Heres the circuit. parts are Q1, MJH10012. Q2,BC337. D1-2, 1N4004. ZD1-4, 75V Zenner diode 3Watt.
LED. C1,10nf. C2,2.2uf. VR1, 10K. R1, 100 ohm 5Watt. R2,1K. R3, 560 ohm. R4, 2.2K. Interesting profile I
used to work as a mechanic for a Ford dealer.

Anyway, here's one circuit to generate a 30Hz input.

The pulse is roughly 32mS wide.

See the attached.

A DIY Power Pulse Controller

This device uses a built in pulse width modulated signal generator circuit for triggering a power MOSFET.

The circuit is great for controlling the power delivered to a device such as a fan, LED’s or even
transformers and coils. By adjusting the pulse width you can easily control the speed of a fan without
sacrificing torque.
The transistor used is not critical but generally something with voltage and current ratings suited to your
application should be used. We have a range of MOSFETs and IGBTs available. The circuit will run from a
6V – 12V DC supply and the output can be made as ‘open collector’ for higher voltage switching.

Don’t fancy building this DIY PWM Circuit yourself? Check out our range of advanced pulse generators

This circuit diagram shows the load (coil, motor etc) connected to the same supply as the rest of the
circuit for simplicity. If you need to switch a higher voltage, the +ve connector of the load can simply be
connected to an external supply.

pwm circuit diagram

Parts List

IC1 LM555

IC2 LM393
R1 10k

R2 10k

R3 2.2k

R4 10k

VR1 1M

VR2 10k

C1 47nF

T1 IRF740 or simlar

If the circuit is to be used with inductive loads a small capacitor should be connected across the load
These are often already fitted on small DC motors. An additional component such as a varistor or
‘freewheel diode’ is also recommended if the pulse generator is driving high voltage flyback transformers
like ignition coils.

The two potentiometers VR1 and VR2 are used for controlling the frequency and duty cycle of the
output. VR1 adjusts the rate at which C1 is charged for modifying frequency, while VR2 acts as a
potential divider allowing a specific voltage to be put on the inverting input of IC2. This voltage is used to
control the pulse width of the output. The output duty cycle or pulse width of the device can also be
controlled by an external voltage such as a microcontrollers or analog signal. The analog voltage source
can simply be connected to the inverting input instead of the output from VR2.

Features and Specifications

Input 9 to 15V, 10A

Power Output – 9 to 15V DC Square wave

Open collector output allows for use of separate voltage source for pulses.

Independent frequency and pulse width / duty cycle controls

Frequency adjustable between 0Hz and 125kHz (C1 must be changed for full range)

Pulse width fully adjustable between 0% and 100%

We have a few of these pulse generators designed for use with high voltage transformers which available
on the cyber circuits page. These are high quality, ready made on a PCB including a large heatsink and
fan, overload protection, and back e.m.f. inductive protection. Theses devices are quite resilient and are
ideal for hobbyists and experimenting due to the wide range of potential uses and durability for handling
varied loads. If you have random transformers or are making your own coils, these power pulse
modulators are ideal for testing and driving them.

Don’t fancy building it yourself? Check out our advanced pulse control circuits. Buy our awesome PWM-
OCXI now!

Injector Driver Circuit; improvment or good to run

I'll start off by saying im very new to electronics and this is the first thing ive built so far. ive made an
injector driver circuit using basically two data sheets for the 2 ic im using, but i have read that data
sheets can be not ideal circuits though. im wondering if there are any changes people would make to
this circuit or if it looks good. i may have added things that are not needed or are wrong, im not sure
exactly what im doing. although i did get this circuit working. my breadboard pic is different then my
circuit drawing, instead of 14.5v its 5v off the arduino, instead of an injector i have an led.

also i made a thread about making a cdi, that explains what im trying to do over all. this project will at all
times be 100% stationary even after completion http://forum.allaboutcircuits.com/threads/mosfet-
driven-cdi-design-help.104857/

here are the pics also C6 is 0.1uf

[IMG] [IMG]
For BOSSCH: Injector type selection, here you can choose For BOSCH ,For DENSO, For DELPHI, For CAT,
in the case of inserting PIEZO Cable, you can choose PIEZO
VL: Fuel injector working selection, here you can choose VE, TL, LL and so on

<: Indicates where the cursor is located

Freq: Frequency setting, range (electromagnetic (1-30HZ), piezoelectric (1-20HZ))

Width: Pulse width setting, range (0-5000us)

Count: Counting settings，range: (1-6000 times, 0 means spraying all the time, not
counting)

Technical Parameters: