Infineon BSS84PH6433 P-Channel Logic Level Power MOSFET: Datasheet, Pinout, and Application Circuits
The Infineon BSS84PH6433 is a P-Channel logic level enhancement mode Power MOSFET housed in a compact SOT-23 package. It is specifically engineered for high-efficiency power management tasks in low-voltage applications, making it an ideal choice for load switching, power management, and battery protection circuits in portable electronics, IoT devices, and other space-constrained designs.
Engineered with Infineon's advanced proprietary MOSFET technology, this device boasts an exceptionally low threshold voltage (VGS(th)) , typically around -1V, allowing it to be driven directly from 3.3V or 5V microcontroller GPIO pins without the need for additional driver circuitry. This feature simplifies design and reduces both component count and board space. Furthermore, it offers a low on-state resistance (RDS(on)) , which minimizes conduction losses and improves overall system efficiency, leading to less heat generation.
Key Datasheet Parameters
Understanding the absolute maximum ratings and electrical characteristics is crucial for a reliable design:
Drain-Source Voltage (VDS): -60 V
Gate-Source Voltage (VGS): ±20 V
Continuous Drain Current (ID): -130 mA
On-State Resistance (RDS(on)): Typically 6.5 Ω at VGS = -4.5 V, ID = -50 mA
Threshold Voltage (VGS(th)): Typically -1 V
Package: SOT-23 (TO-236)
Pinout Configuration
The BSS84PH6433 comes in a standard 3-pin SOT-23 package. The pinout is as follows:
Pin 1 (Gate): This is the control pin. Applying a voltage relative to the source turns the MOSFET on or off.
Pin 2 (Source): This pin is typically connected to the power rail (e.g., battery positive terminal for a high-side switch).
Pin 3 (Drain): The output pin connected to the load.
Application Circuits
Two of the most common circuit configurations for this P-Channel MOSFET are high-side switching and power polarity protection.
1. High-Side Load Switch
This is the primary application for the BSS84PH6433. It is used to connect or disconnect a load from its power supply.
Operation: The source is connected to the positive supply voltage (V+). The drain is connected to one end of the load, with the other end connected to ground. To turn the MOSFET ON, the microcontroller pulls the gate to ground (0V). Since the source is at V+, this creates a sufficient VGS (e.g., -3.3V or -5V) to fully enhance the channel. To turn it OFF, the microcontroller sets the gate pin to a high-impedance state or drives it to V+. A pull-up resistor (e.g., 10kΩ to 100kΩ) from the gate to the source is often used to ensure the MOSFET remains off when the MCU pin is in a high-impedance state.
2. Reverse Polarity Protection Circuit
A single P-Channel MOSFET can provide a highly efficient solution for protecting a circuit from reverse battery connection.
Operation: The MOSFET is placed in the positive supply line. The body diode is initially oriented to allow current flow if the battery is connected correctly. Upon correct connection, the gate is pulled to ground through a large resistor, turning the MOSFET fully on and shorting the body diode, thus minimizing voltage drop. If the battery is reversed, the inherent body diode and the gate-source junction are reverse-biased, ensuring no current flows and protecting the downstream circuitry.
ICGOODFIND Summary
The Infineon BSS84PH6433 stands out as a highly efficient and compact solution for low-voltage power switching. Its logic-level compatibility and low RDS(on) make it exceptionally easy to integrate into modern digital systems, simplifying design while enhancing performance and reliability. Whether for turning subsystems on/off or safeguarding against incorrect power connection, this MOSFET is a versatile and robust component for designers.
Keywords:
1. Logic-Level MOSFET
2. P-Channel
3. Load Switch
4. Low RDS(on)
5. SOT-23
