The HM2305D is HeroMicro a P-channel MOSFET fabricated using advanced trench technology, offering ultra-low on-resistance (RDS(ON)), low gate charge (Qg), and excellent thermal performance. It is optimized for low-voltage applications such as battery-powered devices, load switching, and power management. Housed in a compact SOT-23 package (marked “2305D”), it saves board space while supporting up to -3.8A of continuous drain current.
1. Key Electrical Characteristics (TA = 25°C)
Drain-Source Voltage (VDS): -20 V
Gate-Source Voltage (VGS): ±12 V (absolute maximum)
Continuous Drain Current (ID):
-3.8 A (at TA = 25°C)
-3.0 A (at TA = 70°C, derated at high temperature)
Pulsed Drain Current (IDM): -16.4 A (limited by junction temperature)
On-Resistance (RDS(ON)):
Typ. 35 mΩ (max 45 mΩ) @ VGS = -4.5 V, ID = -3 A
Typ. 45 mΩ (max 65 mΩ) @ VGS = -2.5 V, ID = -2 A
Total Gate Charge (Qg): 6.3 nC (typ.) @ VGS = -4.5 V, VDS = -10 V
Gate Threshold Voltage (VGS(th)): -0.4 V to -0.8 V (@ ID = -250 μA)
Power Dissipation (PD): 1.56 W (at TA = 25°C)
Thermal Resistance (RθJA): 80 °C/W
Operating Junction Temperature: -55°C to +150°C
Package: SOT-23 (3000 pcs/reel)
2. Typical Applications
High-side load switches (e.g., USB power control, IoT device enable)
Power path management in Li-ion battery systems
Reverse polarity protection circuits
Switching element in low-voltage DC-DC converters
Logic-level compatible P-channel switching (direct drive from 3.3V/5V MCUs)
3. Design Considerations
Low Threshold Voltage Advantage:
VGS(th) as low as -0.4 V enables reliable turn-off with minimal gate drive, ideal for low-power standby designs.
However, this sensitivity may cause unintended turn-on due to noise—add a 100 kΩ pull-down resistor from gate to source for stability.
Logic-Level Compatibility:
At VGS = -2.5 V (compatible with 2.5V logic), RDS(ON) remains below 65 mΩ.
Ideal for 1.8V/3.3V/5V systems—no level-shifting circuitry required.
Recommended drive range: -2.5 V to -4.5 V.
Thermal Management:
With RθJA = 80°C/W, 1W of power dissipation raises the junction temperature by 80°C above ambient.
Use ≥2 mm² copper area on drain and source pads to improve heat spreading.
For continuous operation, limit current to ≤2.5 A (at TA = 25°C).
Switching Performance:
Turn-on delay (td(on)): 4 ns
Turn-off delay (td(off)): 40.6 ns
Low Qg (6.3 nC) enables fast switching:
Suitable for medium-frequency PWM (e.g., ≤100 kHz), but consider EMI mitigation.
Body Diode Characteristics:
Intrinsic body diode has VSD ≤ -1 V (@ ISD = -1 A), useful for freewheeling in inductive loads.
4. PCB Layout Recommendations
SOT-23 Pinout (top view, marking facing up):
Pin 1: G (Gate)
Pin 2: S (Source)
Pin 3: D (Drain)
Connect source (S) to the positive supply rail (in high-side configuration).
Keep drain (D) trace short and wide to handle load current.
Route the gate trace away from high dV/dt nodes; add a 10–47 Ω series resistor if ringing occurs.
