AO4818B

Overview

The AO4818B is a dual N-channel MOSFET manufactured by Alpha & Omega Semiconductor Inc. utilizing advanced trench technology for low on-resistance and gate charge. It features a drain-source voltage (VDS) of 30V, continuous drain current (ID) of 8A at VGS=10V, and maximum on-resistance (RDS(ON)) of less than 19mΩ at VGS=10V and 26mΩ at VGS=4.5V. The device includes ESD protection and is 100% UIS tested. It operates within a junction temperature range of -55°C to 150°C and is housed in an SOIC-8 surface-mount package.

Feature Summary

• Advanced trench technology provides excellent RDS(ON) performance and low gate charge characteristics.
• Integrated electrostatic discharge (ESD) protection mechanisms are included.
• Verified reliability through 100% Unclamped Inductive Switching (UIS) testing.
• Suitable for use as a load switch or in pulse-width modulation (PWM) applications.

Applications

• Load switching circuits
• Pulse-width modulation (PWM) control systems

Procurement Notes

Verify the specific datasheet revision against the manufacturer's official documentation before implementation. Confirm that the SOIC-8 package dimensions and pinout align with the target PCB footprint. Ensure thermal management strategies account for the specified junction-to-ambient resistance values under actual operating conditions.

Selection Notes

Select this component when a dual N-channel configuration is required within a 30V system. The logic-level gate threshold supports efficient driving from standard logic outputs. Evaluate the thermal dissipation requirements based on the specific board copper area and airflow conditions, as the junction-to-ambient resistance varies significantly with layout design.

Part Context

This part belongs to the AO481 series of dual N-channel MOSFETs produced by Alpha & Omega Semiconductor. The AO4818B specifically targets applications requiring moderate current handling in a compact surface-mount form factor. It complements other devices in the family offering different voltage or current ratings while maintaining consistent packaging standards.

Replacement Considerations

Direct substitutes must match the 30V rating, dual N-channel topology, and SOIC-8 package. Verify that alternative components meet the same RDS(ON) specifications at both 10V and 4.5V gate voltages to ensure equivalent circuit performance.

FAQ

What is the maximum gate-source voltage rating?

The absolute maximum gate-source voltage (VGS) is rated at ±20V.

Is the device suitable for high-frequency switching?

Yes, the device exhibits fast switching times, including a turn-on rise time (tr) of 3.5ns and a turn-off fall time (tf) of 3.5ns, supporting high-frequency PWM applications.

How is the body diode reverse recovery characterized?

The body diode reverse recovery time (trr) is typically 6ns and maximally 10ns when tested at IF=8A and dI/dt=500A/ms.