The IRF7309 is HeroMicro a dual-channel power MOSFET integrating one N-channel and one P-channel device in a single SOP-8D surface-mount package. Designed for high-efficiency, space-constrained power management applications, it leverages advanced trench technology to deliver ultra-low on-resistance (RDS(ON)), low gate charge, and excellent thermal performance. It is ideal for load switching, H-bridge motor drives, battery protection, DC-DC converters, and portable power control systems.
1. Device Overview
Configuration: 1 N-channel + 1 P-channel MOSFET (independently accessible)
Package: SOP-8D (8-pin surface-mount)
N-Channel Specifications:
≤28 mΩ @ VGS = 10 V, ID = 7.2 A
≤36 mΩ @ VGS = 4.5 V, ID = 5 A
Drain-Source Voltage (VDS): +30 V
Continuous Drain Current (ID): 7.5 A (TA = 25°C)
On-Resistance (RDS(ON)):
P-Channel Specifications:
≤52 mΩ @ VGS = –10 V, ID = –6.3 A
≤65 mΩ @ VGS = –4.5 V, ID = –4.5 A
Drain-Source Voltage (VDS): –30 V
Continuous Drain Current (ID): –7 A (TA = 25°C)
On-Resistance (RDS(ON)):
Maximum Power Dissipation (PD): 2 W (TA = 25°C)
Thermal Resistance (RθJA): 62.5 °C/W (mounted on 1 in² copper PCB)
Gate-Source Voltage (VGS): ±20 V (maximum)
2. Key Usage Guidelines
(1) Logic-Level Compatibility
The N-channel achieves 36 mΩ at VGS = 4.5 V; the P-channel achieves 65 mΩ at VGS = –4.5 V. Both are compatible with 5 V or 3.3 V logic, enabling direct drive from microcontrollers or PWM controllers.
(2) Thermal Management
Power dissipation is limited to 2 W. Continuous current must be derated at elevated ambient temperatures.
Use large copper areas on the PCB for thermal pads (e.g., pins 2, 4, 6, 8) and connect them to inner ground planes via multiple vias to reduce thermal resistance.
Calculate total power loss (conduction + switching) to ensure junction temperature stays below 150°C.
(3) Body Diode Characteristics
N-Channel Body Diode:
VSD ≤ 1 V (@ IS = 2.5 A)
trr = 12.6 ns (@ IF = 7.2 A)
P-Channel Body Diode:
VSD ≥ –1 V (@ IS = –3.5 A)
trr = 15 ns (@ IF = –5.3 A)
Body diodes can provide freewheeling paths, but their reverse recovery may cause EMI. Add snubber circuits in noise-sensitive applications.
(4) Safe Operating Area (SOA)
Refer to the SOA curves (Fig. 9) in the datasheet. Avoid prolonged operation at high voltage and high current simultaneously, especially for pulse widths >10 ms.
(5) PCB Layout Recommendations
Keep gate traces short to minimize noise coupling.
Use wide power and ground traces to reduce parasitic inductance.
Connect N-channel source (S1) to system ground and P-channel source (S2) to supply rail separately—avoid shared high-impedance paths.
3. Typical Applications
Power/load switching in portable devices
Low-power H-bridge motor drives (e.g., fans, small pumps)
Battery charge/discharge path control (charge/discharge MOSFET pair)
Synchronous rectification in bidirectional DC-DC converters
Logic-level-compatible high-side/low-side switches
4. Summary
The IRF7309 offers a compact, efficient solution for low-voltage, medium-current power systems by integrating complementary N+P MOSFETs with ultra-low RDS(ON) and logic-level drive capability in a space-saving SOP-8D package. By properly designing gate drive, optimizing thermal layout, and respecting electrical and thermal limits, engineers can achieve reliable, high-performance operation in a wide range of modern electronic applications.
