The HM639B is HeroMicro a complementary dual MOSFET device integrating both N-channel and P-channel transistors in a single TO-252-4 (DPAK) package. Built with advanced high-cell-density trench technology, it delivers ultra-low on-resistance (RDS(ON)), low gate charge (Qg), and excellent thermal performance—making it ideal for medium-to-high power applications such as H-bridge motor drives, power switching, and battery management.
1.Key Electrical Characteristics (TC = 25°C)
2. Typical Applications
H-bridge or half-bridge motor drivers (e.g., power tools, fans, pumps)
High-current load switches (e.g., automotive electronics, industrial controls)
Battery charge/discharge management and reverse polarity protection
Synchronous rectifiers in DC-DC converters
Bidirectional power path control
3. Design Considerations
Optimal Gate Drive:
N-channel: Use VGS = 10 V for lowest RDS(ON) (<5.5 mΩ); still <7 mΩ at 4.5 V.
P-channel: Drive with VGS = -10 V to achieve RDS(ON) < 15 mΩ.
Both channels support logic-level drive, but 10 V is recommended to minimize conduction losses.
Superior Thermal Performance:
Extremely low RθJC (2.3°C/W) enables efficient heat transfer to PCB or heatsink.
Capable of dissipating 55 W continuously (at TC = 25°C), ideal for high-power-density designs.
High Current Capability:
N-channel handles up to 60 A continuous current; P-channel up to 38 A.
High pulsed current ratings (N: 250 A, P: 125 A) support inrush or overload conditions.
Switching & EMI Control:
N-channel Qg = 25 nC (@ VGS=4.5V), enabling fast switching.
Add a 3–10 Ω gate resistor in high-frequency applications to suppress ringing and control dV/dt.
Body Diode & Safe Operating Area (SOA):
Intrinsic body diode has VSD ≤ 1 V (@ IS = 1 A), suitable for freewheeling.
Refer to the Maximum Safe Operating Area (SOA) curve in the datasheet—ensure operation stays within limits, especially during short-circuit or linear-mode conditions.
Reliability:
Compliant with green (RoHS) standards.
All ratings are specified at TC = 25°C; derate current at elevated case temperatures (see Fig. 10 in datasheet).
4. PCB Layout Recommendations
TO-252-4 Pin Configuration (typical):
G1 (N-gate), D1 (N-drain, connected to thermal pad)
G2 (P-gate), S1/S2 (N/P sources, often separate)
Solder the large drain thermal pad to a copper pour (top or inner layer); consider a heatsink for >30 W operation.
Keep gate traces short and isolated from high-current paths.
In H-bridge configurations, implement dead time to prevent shoot-through between N and P devices.
