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Smart H-Bridge, with Aluminum Plate Heat-Sink, 5kHz or 20kHz PWM Soft-Start and Soft-Stop, Active Low Control Inputs, Y-Chip
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Si24SB4-30V-20A-AP1 Spec Sheet (PDF) |
The Si24SB4-30V-20A-AP1 is a 30V 20A, microprocessor based, high-power, Smart H-Bridge with a small (4.0"x3.3"x0.065") Aluminum Plate Heat Sink and with user selectable Soft-Start and Soft-Stop features. This controller uses a single (9V to 30V at 0 to 20A) DC power supply to control the speed of a DC motor (or load-current) in forward or reverse direction. An onboard microprocessor generates a 5kHz or 20kHz PWM carrier signal, controls the load-power (or motor speed), controls the load-current rate (or motor acceleration and deceleration). The PWM carrier frequency is user selectable by the jumper J2, 20kHz when J2 is open and 5kHz when short. This high frequency PWM rate insures a quiet motor environment. The user can choose between slow or fast (Soft Select) motor acceleration/deceleration modes by short-circuiting or open-circuiting the pins labeled J1. The slow mode, with rise-time/fall-time of 1.25Sec, is selected by short-circuit (J1 jumper installed); while the fast buildup mode, with rise-time/fall-time of 0.05s, is selected by leaving these pins open (no Jumper installed). As the name “Smart” implies the required motor speed (or PWM pulse-duration) is variable from 0 to 100% in 0.83% steps using the analog voltage (VP1,G on CN6), while the motor direction (or Load-Current Direction) is selected using two active low digital (0 to +5V) control signals (VF,N and VR,N) or switches. All inputs are optically isolated or zener-diode protected. A bicolor LED is used to monitor the motor (or load) voltage (Red = Forward, Green = Reverse). A small (4.0”x3.3”x0.062”) Aluminum Plate Hear-Sink is used to operate at 20A current levels. Higher current-levels (25A or 750W) can be achieved with more efficient heat-sinks. Please click on this link and read the Board Mounting Instructions and Heat Sink Selection Guide. This board operates in a wide voltage-range (9V to 30V) at max. continuous load current of 20A. Typical applications are: Bi-directional DC Motor-Speed Controller, Peltier Effect TE Coolers, Heat Pumps, DPDT Solid State Relay, etc. This board can be configured and programmed to perform efficiently in many customized applications.
Motor Control-Action Truth Table, (Pins on Connector CN4)

A Typical Application of the Si24SB4-30V-20A-AP1
In this open-loop application, the PWM or motor speed (in forward or reverse direction) is adjusted by an external linear 1-turn 5kW potentiometer (Signal Part number Si24PB2-MC3 ) and the motor direction is controlled by 4 external switches connected to port CN4 (as shown below). The normally-open switches select the motor direction, while the optional normally-closed limit-switches are included to prevent over-rotation in window-lifting applications. Warning: The connecting wires to the Load and the Power Supply must be heavy gauge copper wire (#12 AWG or heavier) to handle the rated current level. In addition, these heavy gauge wires act as a heat sink, protecting the board from overheating.

| Si24SB4-30V-20A-AP1, Smart H-Bridge with Aluminum Plate Heat Sink |
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Note: If Buying the Si24SB4-30V-20A-AP1, it is recommended to buy one Si5Pot1-5k Pot, and a Si24PB2-MC3 Two Push-Buttons with 12" lead and with a 3-pin FM Molex Connector. |
| Si5Pot1-5k One 1-Turn, 5kW Potentiometer with 12" leads. |
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| Si24PB2-MC3 Two Push-Buttons with 12" lead and with a 3-pin FM Molex Connector. |
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Availability: We usually ship in 2-3 business days.
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All Products Are Proudly Made in the USA
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