Fig. 1b
High Current Tri-State MOSFET Driver Circuit
Webmaster Homepage and contact information.
This will serve as an introduction to Tri-State power driver circuits. This is oriented towards H-Bridge motor controls.
The circuit reviewed here is not tri-state, but high-low output depending on the input. The input will be not inverted.
The ultimate goal is the H-Bridge shown as hb_big1.jpg
Fig. 1b uses an open collector 75LS06 with a pull up resistor. See Review Connecting Digital Logic and Transistors
Related:
HIGH is +5V and LOW is 0V unless specified otherwise. This assumes a 5-volt microcontroller.
The concept here is to drive heavier loads from a microcontroller I/O pin. Most are limited to 25-40mA This circuit can source-sink several amps.
Fig. 2
Fig. 2 circuit is non-inverting. HIGH in is HIGH out. LOW in is LOW out. When DIN is HIGH the output of the 7404 goes LOW. This turns on Q1 a P-channel MOSFET power transistor, turns off Q2 a N-channel MOSFET.
A load such as an LED connected between Y and ground would turn on.
If DIN is LOW The output of the 7404 goes HIGH. Q1 is turned off, Q2 is turned on. This is the "sink" mode. A load such as an LED connected between Y and +5V will turn on.
Fig. 3 Sink current demo circuit.
Fig 4 Source current demo circuit.
Fig 5 High voltage buffer circuit using ULN2003 and pull up resistor.
Fig. 6
Here I use two identical circuits each connected to one side of a DC motor. Two inputs can forward or reverse the motor rotation. Note the truth table. Only when the inputs A and B differ does the motor operate.
Related links:
- Optical Isolation of H-Bridge Motor Controls
- All NPN Transistor H-Bridge Motor Control
- Basic Transistor Driver Circuits for Micro-Controllers
- ULN2003A Darlington Transistor Array with Circuit Examples
- Tutorial Using TIP120 and TIP125 Power Darlington Transistors
- Driving 2N3055-MJ2955 Power Transistors with Darlington Transistors
- Understanding Bipolar Transistor Switches
- N-Channel Power MOSFET Switching Tutorial
- P-Channel Power MOSFET Switch Tutorial
- Build a Transistor H-Bridge Motor Control
- H-Bridge Motor Control with Power MOSFETS
- More Power MOSFET H-Bridge Circuit Examples
- Build a High Power Transistor H-Bridge Motor Control
- H-Bridge Motor Control with Power MOSFETS Updated
- Opto-Isolated Transistor Drivers for Micro-Controllers
View all of my You Tube Videos
Also visit and subscribe to My YouTube Channel
- High current TTL MOSFET Driver Circuit
- Non-Inverting Tri-State Buffer-Switch Demo Circuit
- Review Connecting Digital Logic and Transistors
- Tri-State H-Bridge Uses Optocouplers
- Driving Darlington Transistors with Optocouplers
- Optocouplers for TTL-CMOS Logic Level Shifting
- Basic TTL Tri-State Buffer Circuit Examples
- H-Bridge Schematic with MOSFET Outputs
- H-Bridge Schematic with Darlington-MOSFET Transistor Outputs
- H-Bridge schematic with Darlington-IGBT Transistor Outputs
- Tutorial NOR Gate SR Latch Circuits
- Tutorial NAND Gate SR Latch Circuit
- From SR Latch to Microcontroller IO Pin Introduction
- From Basic Digital Circuits to H-Bridge Motor Controls
- Youtube videos:
- Driving High-Power Darlington Transistors
- Four MOSFET Tri-State Switch
- Overview Toshiba IGBT Application Notes
- MOSFETs and Electron Flow
- 3.3 Volt Logic Controls H-Bridge TTL Input
- H-Bridge Driving Large Motor
- Simple Digital Interface Circuits
- OptoCoupler Interfacing H-Bridge Circuits
- Why Your MOSFET Transistors Get Hot
- Unrelated videos:
- Reality of Recycling Low-Value Ewaste
- Magnetron Operation and Free Magnets
- Comparing Photo Triac, Photo SCR Opto-Couplers
- Light Activated SCR Based Optocouplers Circuit Examples
- Silicon Controlled Rectifier Review and Circuits
- Silicon Controlled Rectifiers Connected as Power Triacs
- Insulated Gate Bipolar Transistor IGBT Circuits
- Current Limiter Circuits for Opto-Coupler LEDs
- VOM1271 Photovoltaic MOSFET Driver Circuits
- Current Limiter Allows Safe Testing of Zener Diodes, LEDs
- 3 Amp LM741 Op-Amp Constant Current Source
- Bidirectional Solid State Relay Circuits
- Simple Solid State Relay for Low Power LED 120V Lamps
- Build High Power MOSFET Bidirectional Switch Relay
- Exploring Solid State Relays and Control Circuits