For more files and detailed information download the Instruction Manual on the Tech Info page.

The BE-SP6A has control circuits to drive 1 Stepper Motor in ½ step mode, both directions.
It uses a Dual H bridge IC to drive a 4 wire Bipolar or a 6/8 wire Unipolar Stepper.

4 ways to control Stepper Circuit:

1 Two Switches, using internal automatic step clock.
2 Two Switches, with manual step clock.
3 External with 2 signals supplied from BE-SP3. (Step and Direction Bits)
4 Controlled from your Computer or Micro.

BE-SP6A  with heat sink


BE-SP6A Circuit Specifications:

BE-SP6A Circuit Specifications:
The BE-SP6A is a Stepper Driver Circuit with several options.
It runs Stand-alone, BE-SP3 driven, or uses your Micro.

Recommended operating conditions:

BE-SP6A control Input Voltage 7 to 18 VDC ( 9VDC is best )
BE-SP6A control Input Current @ 9VDC 40-55 mA. No external loads.
BE-SP6A Power Driver Input Voltage 5 to 46 VDC
BE-SP6A Power Driver Input Current ** 4 Amps per package or 2 Amps on 2 channels (<25W).
BE-SP6A Output VCC 5V and < 100mA (used for auxiliary circuit drive power).

Stepper runs in ½ step mode. A stepper in ½ step mode needs 400 pulses for 1 full turn.

Operating temperature. 0c to 70c ( Open air ).


CLK Input Voltage range. 0 to 5 VDC Analog levels. Factory set at 2.5 volt crossing.
DIR Input Voltage range. 0 to 5 VDC Analog levels. Factory set at 2.5 volt crossing.
RA to RB resistor Values. 100k or higher. Below 100k may run motor to fast

External CLK Speed. 0 pulses per second to whatever the Stepper will handle.

Internal default Clock Speed, no (RA RB) ~ 125 pulses per second = 7500/min = 18.75 RPM
Fast Clock Speed, (RA RB =~100k) ~ 625 pulses per second = 37500/min = 93.75 RPM

** Driver IC's ( 1 on board) will drive up to 25 watts, or up to 1 Amp continuous per channel.
Use fan and/or add Appropriate heatsink(s) when needed.

Max Driver Volts = 50. (Recommended Volts = 46).

One 4 channel Driver IC can drive:
2 channels with 2 Amps each or
4 channels with 1 Amp each.

Do not exceed power ratings, see load chart for more details.




Gates (A and B) are part of an oscillator (Clock) circuit that can only run if pin 2 has a high (5V) on it.
Adding resistor(s) or a pot across T1-4 (RA) and T1-5 (RB) will speed up the oscillator.

If gate B pin 6 is connected to the 191 through J1, then the stepper will run at oscillator speed.
If gate C pin 11 is connected to the 191 through J1, then the stepper will move one step on each fall of the clk signal.

When the J1 Jumper is on right, the output from gate B goes to the control circuits of the Driver.
Each CLK pulse moves the Stepper one Step. It will run until the CLK input goes High (+5).

Gates (C and D) are part of a Led drive and buffer circuit that will clean up outside clocks.

The 393 comparators will clean up the Clk and Dir signals by comparing them to known voltage levels.That gives gates C and D a nice input signal to drive the 191 counter.

Refer to BE6A Info sheet file on Tech Info page.


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