The HM4618 is HeroMicro a complementary MOSFET pair integrating both N-channel and P-channel devices in a single SOIC-8 package. Built with advanced trench technology, it offers low on-resistance (RDS(ON)) and minimal gate charge (Qg), making it ideal for low-voltage inverter, H-bridge driver, and power switching applications.
1. Key Electrical Characteristics
| Parameter | N-Channel | P-Channel |
|---|---|---|
| Drain-Source Voltage (VDS) | +40 V | -40 V |
| Continuous Drain Current (ID, TA=25°C) | +8 A | -7 A |
| RDS(ON) (Typical) | 15.4 mΩ @ VGS=10V, ID=8A | 19 mΩ @ VGS=-10V, ID=-7A |
| Total Gate Charge Qg (10V) | 6.4 nC | 32 nC |
| Gate Resistance Rg | 2.2 Ω (typ.) | 4.5 Ω (typ.) |
| Body Diode Reverse Recovery Time (trr) | 7.3 ns | 13 ns |
2. Typical Applications
Low-voltage H-bridge or half-bridge drivers (e.g., motor control, DC-AC inverters)
Synchronous rectification
Power switches in battery-powered devices
Logic-level compatible load switches (supports 4.5V gate drive)
3. Design Considerations
Gate Drive Voltage:
N-channel: Drive with ≥4.5V (10V recommended for lowest RDS(ON)).
P-channel: Drive with ≤ -4.5V (-10V optimal).
At 4.5V drive, RDS(ON) remains low (N: <27 mΩ; P: <30 mΩ), suitable for 3.3V/5V systems.
Thermal Management:
Maximum power dissipation is 2 W at TA = 25°C, but highly dependent on PCB layout.
Steady-state junction-to-ambient thermal resistance (RθJA) can reach 90°C/W. Use wide copper traces or internal ground planes to improve heat spreading.
Switching Timing & Dead Time:
The N-channel switches significantly faster than the P-channel (e.g., N-channel turn-on delay: 4.5 ns vs. P-channel: 10 ns).
In bridge configurations, always implement dead time to prevent shoot-through current.
Body Diode Usage:
The intrinsic body diodes can be used for freewheeling, but note that the P-channel diode has higher reverse recovery charge (Qrr = 33 nC) compared to the N-channel (11 nC), leading to higher switching losses at high frequencies.
Reliability & Safety:
100% tested for UIS (Unclamped Inductive Switching) and gate resistance (Rg) to ensure consistency.
Qualified for consumer electronics only—not authorized for use in life-support or safety-critical systems.
4. PCB Layout Recommendations
Use wide and short traces for power and ground to minimize parasitic inductance.
Keep gate drive lines as short as possible to reduce ringing and EMI.
Although the SOIC-8 package has no exposed pad, pins 4 and 5 (common Drain connection) can be used as a thermal path—connect them to a copper pour for better heat dissipation.
