Infineon BSP295H6327 P-Channel Enhancement Mode Power MOSFET: Datasheet, Pinout, and Application Circuit Design
The Infineon BSP295H6327 is a high-performance P-Channel Enhancement Mode Power MOSFET housed in a compact SOT-223 surface-mount package. Engineered for efficient power management, this MOSFET is a cornerstone component in modern electronic design, particularly in applications where space, thermal performance, and efficiency are paramount. This article delves into its key specifications, pinout configuration, and a practical application circuit to guide design engineers.
Datasheet Overview and Key Specifications
The BSP295H6327 is characterized by its low on-state resistance (RDS(on)) and high current handling capability, which are critical for minimizing power losses and heat generation. Key absolute maximum ratings and electrical characteristics from its datasheet include:
Drain-Source Voltage (VDS): -20 V
Continuous Drain Current (ID): -4.3 A
On-State Resistance (RDS(on)): Typically 47 mΩ at VGS = -10 V
Gate-Source Voltage (VGS): ±20 V
Threshold Voltage (VGS(th)): Typically -1 V
Being a P-Channel MOSFET, all voltage and current values are typically expressed as negative. Its low threshold voltage makes it suitable for use in low-voltage drive circuits, including those powered by 3.3V or 5V microcontroller GPIO pins.
Pinout Configuration
The device comes in a SOT-223 package, which offers a good balance between size and power dissipation. The pinout is standard for this package type:
1. Pin 1 (Gate): This is the control pin. The voltage applied between the Gate and Source (VGS) controls the flow of current between the Drain and Source.
2. Pin 2 (Drain): The output terminal. For a P-Channel MOSFET used as a high-side switch, the load is connected between the Drain and ground.
3. Pins 3 & 4 (Source): These two pins are internally connected and represent the common source terminal. They are typically tied to the positive supply rail (VCC). Using two pins enhances current capacity and improves thermal performance by connecting a larger copper area to the PCB.
Application Circuit Design: High-Side Load Switch
A quintessential application for the BSP295H6327 is a high-side load switch, commonly used to control power to a load (e.g., a motor, LED strip, or another circuit module) from a microcontroller (MCU).
Circuit Operation:
1. The Source pin is connected directly to the main power supply (e.g., +12V).
2. The Drain pin is connected to the positive terminal of the load. The negative terminal of the load is connected to ground.
3. A gate resistor (e.g., 10kΩ) is placed between the Gate and the Source. This is a pull-up resistor that ensures the MOSFET remains off (VGS = 0V) when the MCU output is in a high-impedance state (e.g., during startup or reset).
4. The MCU's GPIO pin is connected to the Gate through a current-limiting resistor (e.g., 100Ω). This resistor dampens any ringing caused by parasitic inductance and the MOSFET's gate capacitance.
How it Works:
To Turn OFF the Load: The MCU GPIO is set to a logic HIGH (e.g., 3.3V). Since the Source is at +12V, the VGS is 3.3V - 12V = -8.7V. This is not a sufficiently negative voltage to turn on the P-Channel MOSFET (which requires VGS < -1V), so it remains off.
To Turn ON the Load: The MCU GPIO is set to a logic LOW (0V). Now, VGS becomes 0V - 12V = -12V. This is well below the threshold voltage, fully enhancing the MOSFET and allowing current to flow from the Source to the Drain, thus powering the load.
This circuit is highly effective because it allows a low-voltage MCU to safely control a higher-voltage, higher-current power rail with minimal components and high efficiency.
ICGOOODFIND
The Infineon BSP295H6327 is an excellent choice for designers seeking a robust and efficient P-Channel MOSFET for power switching tasks. Its low RDS(on) and compact SOT-223 package make it ideal for space-constrained applications requiring minimal voltage drop and heat generation. The straightforward high-side switch circuit demonstrates its practicality in enabling safe MCU-based control of various DC loads, solidifying its role as a fundamental component in power management design.
Keywords: P-Channel MOSFET, Low RDS(on), High-Side Switch, Load Switching, SOT-223 Package.
