Signal Consulting, LLC 

Model Si24SB4-VD2-30V-20A-AP1

Smart H-Bridge, with Variable or Fixed Ramp Delay Time for Soft-Start and Soft-Stop, Integrated Aluminum Plate Heat-Sink, 5kHz or 20kHz PWM, Active Low Control Inputs, Y-Chip  





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Si24SB4-VD2-30V-20A-AP1 Features:

Efficient H-Bridge: for Bidirectional Current Control
Directional Control: with External Forward, Reverse Keys
Max. Current for 5 sec : 40A with Proper Heat-Sink Installed
Max. Continuous Current: 20A with Proper Heat-Sink

Two User Selectable PWM Frequency: 5KHz or 20kHz

Two User Selectable Motor Acceleration/Deceleration Modes:  Using Jumper on Port J1.

Variable Ramp-Time: 0 to 2.0sec

Adjustable Load Voltage (RPM): The average Load-Voltage (or motor RPM) is adjustable from 0V to 30V  (or max. value of Vp) in 0.83% steps with a Pulse-Width Modulation (PWM) control signal or with an internal/external potentiometer.

High Power-Efficiency: 98.5% typical, at 50V and 20A
Optically Isolated Directional Control Signals
Power Semiconductors: Four 60A Hex-MOSFETs
Dimensions: 2.9" x 2.9" x 1.4" (7.4cm x 7.4cm x 3.4cm).
Components Type: 100% Solid State, NO Relays

On Board:
Filter Capacitors
VTS diodes
Snubber Circuit Ready
  Bicolor LED Indicator,  (red=forward,  green= reverse)

Voltage Requirement:
A single DC Source Voltage (unregulated and Unfiltered) with any voltage value from 9V to 30V (for Vp)

Si24SB4-VD2-30V-20A-AP1  Spec Sheet  (PDF)

The Si24SB4-30V-20A-VD2-AP1 is a 30V 20A, microprocessor based, high-power, Smart H-Bridge with a small (4.0”x3.3”x0.062”) 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 variable delay-mode (variable motor acceleration/deceleration) or can choose a fixed delay-mode. In the variable mode (with jumper J1 installed), the rise-time/fall-time varies linearly with the analog voltage on pin I2 (VI2,G on CN6) (from 0.1sec=0V to 2.0 sec=+5V). In the fixed mode (with jumper J1 open) the rise-time/fall-time is fixed to approximately 2sec. 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 (VI1,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”x0.065”) integrated 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 50V) 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)


 The motor action or load-current direction is controlled by active low control inputs, (0 to +5V) applied to Pin F (Forward) and/or pin R (Reverse) relative to Pin N (Neutral) on the Connector CN4. These pins are optically isolated from the H-Bridge, providing good noise immunity for these inputs. The control actions and the required voltage levels are defined by the Truth-Table listed above. All control lines (analog and digital) are sampled approximately at 80Hz rate in the fast mode (J1 jumper open), and at 8Hz rate in the slow mode (J1 jumper short). 

A Typical Application of the Si24SB4-VD2-30V-20A-AP1

 In this open-loop application, the PWM (or motor speed) and the ramp up/down time (motor acceleration/deceleration) in forward or reverse direction are independently adjusted with two external linear 1-turn 5kW potentiometers (Signal Part number Si5Pot1-5k ) and the motor direction is controlled by 4 external switches (Signal Part number Si24PB2-MC3 ) 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-VD2-30V-20A-AP1, Smart H-Bridge with variable of fixed ramp-time and with Aluminum Plate Heat Sink  
Price $199.00

Note: If Buying the Si24SB4-VD2-30V-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.  
Price $15.00
Si24PB2-MC3   Two Push-Buttons with 12" lead and with a 3-pin FM Molex Connector.  
Price $29.00

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Availability: We usually ship in 2-3 business days.



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