Square Wave Generator (0.07 Hz - 2 kHZ)

Applications: 

1. Generate a square wave signal for experimental development.

2. Generate drive a stepper motor drive square wave signal.

3. Adjustable pulse generation MCU for use.

4. Have an adjustable pulse control related circuit.

5. The duty cycle and frequency are adjustable

Specification: 

1. Size: 3.5cm X 4.6cm 

2. main chip: LM358

3. Input voltage: 5V - 12VDC

4. the input current: ≥100MA

5. output amplitude: close to the input voltage

6. frequency adjustment range: 0.07 Hz - 2 kHz (ie period about 0.45 msec to 15 sec)

Frequency adjustment method:

Board has 4 short-circuit cap may select the frequency. 
Insert 0 short-circuit cap: period can be adjust to about 0.3 seconds. 
Insert 1 short-circuit cap: period can be adjusted up to 4 seconds. 
Insert 2 short-circuit cap: period may be adjusted to about 7 seconds. 
Insert 3 short-circuit cap: period may be adjusted to about 10 seconds. 
Insert 4 short-circuit cap: period may be adjusted to about 15 seconds.

7. duty cycle adjustment range: 0% to 100% (high / cycle).

8. output current: strip transistor 9012, so the drive capacity is relatively strong, the output current can go about 500mA, output can directly drive a small relay or small motors.

Advantages: 

1. duty cycle and frequency resolution is adjustable. 

2. output with LED indication, there is no straightforward output (LED lights at a high level, low level LED off, LED flashes relatively low frequency, high frequency LED will be lit, because the naked eye can not be seen).

3. circuit diagram is supplied.