Signal Consulting, LLC 

Model Si30HFHB-50V-30A-ALC 

50V-30A High-Frequency H-Bridge, DC to 20kHZ PWM, with Active-Low Control, Integrated Finned Heat-Sink, for Bidirectional DC Motor Driver





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Si30HFHB-50V-30A-ALC Features:

Power Semiconductors: Eight 90A MOSFETs.

Overall Dimensions : 4.6”x2.43”x2.0”, (117 x 62 x 52 mm).

Load Isolation: The Load must be Isolated from the  Power Source.

Max. Continuous Current: 30A with Heat-Sink (as shown).

Max. Current for 5 sec: 50A with Heat-Sink ( as shown ).

Power-Conversion Efficiency: Approx. 98.5% (at 50V, 30A).

Control Type: Active Low (+5 to 0V).

Worst-Case Control Latency: 7 micro seconds.

Load Voltage Rise or Fall-Time (10% to 90%): 12 micro seconds.

Voltage Requirements: A single DC Source (unregulated or regulated ), any voltage from 12V to 50 V DC.

Load-Voltage Indicator: Bicolor LED.

Onboard 30A Fast Mini-Blade Auto Fuse: Replace, from  DigiKey, Part Number: F6079-ND

Components Type: 100% Solid State, NO Relays

On Board: 
Filter Capacitors
VTS diodes
Snubber Circuit included


    For Details, Download the  Si30HFHB-50V-30A-ALC-1Y2   Manual


The Si30HFHB-50V-30A-ALC is a 50V 30A, microprocessor based, high-power, High-Frequency H-Bridge with active-low control inputs. This controller requires two active Low inputs (or two 0 to 20kHz PWM inputs) on pin I1 and on pin I2 to control the speed and rotation direction of a DC motor (as shown on the truth table given below). An onboard microprocessor samples the control inputs at 150kHz rate and generates the timing signals for the H-Bridge. The high sampling rate provides a worst-case control latency of 7uS when the bridge is changing current direction or switching on or off. Two active low digital (0 to +5V) control signals (VF,G  and VR,G) or switches are used to select the direction of rotation (or Load-Current Direction). These inputs can be Pulse Width Modulated (PWM) from DC to 20kHz carrier rate. This board uses a single (12V to 50V at 30A) DC power supply to control the speed of a DC motor (or load current) in forward or reverse direction. A bicolor LED is used to monitor the motor (or load) voltage (Red = Forward, Green = Reverse). A small (4.6”x2.4”x1.0”) integrated finned heat-sink is used to operate the bridge at 30A (continuous) current levels. Higher current-levels (40A) 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 (12V to 50V) at a maximum continuous load-current of 30A. 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.            

ALC Control Truth Table (on connector CN4)

         The control lines F and R (VF,G , VR,G) can be Pulse-Width Modulated (PWM in a range of 0-20k Hz) to vary the average current supplied to a load or to a DC Motor.

         Typical Input Resistance of I1 and I2 is 4.7kOhm, relative to pin +5V

 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 control signals are optically isolated from the high-side of the H-Bridge, providing good noise immunity. The control actions and the required voltage and current levels are listed in the Truth-Table (given above). 

Frequency Response of the Si30HFHB-50V-30A-ALC

This plot shows the maximum average load current as a function of PWM carrier frequency (in Hz) at 100% duty-cycle. This plot was obtained with the finned heat-sink (4.6” x 2.4” x 1.0”, as shipped with the unit). Improved performance can be achieved with more effective heat-sinks.

A Typical Motor Control Application of the Si30HFHB-50V-30A-ALC

 In this open-loop application, the motor direction is controlled by 2 external normally-open switches connected to pins F (forward) and R (reverse) on port CN4 (as shown below).

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. Note that each connecting point on CN1 is available at 2 places, thus two smaller wires can be used in place of a larger one.

Typical Applications: Bidirectional Speed Controller, Bidirectional DC Motor Driver. Peltier Effect or TE Cells Driver, Heat Pump Controller, PPDT Solid State Relays.

Si30HFHB-50V-30A-ALC  50V at 30A, High-Frequency H-Bridge with Integrated Finned Heat-Sink , Active Low Cont. 
Price $279.00

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



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