CS19N40A8H MOSFET — Specifications & Equivalents

About the CS19N40A8H

The CS19N40A8H is a MOSFET with a drain–source voltage (V_DS) rating of 400 V and a continuous drain current (I_D) of 19 A. It can dissipate up to 180 W and is rated to a junction temperature of 150 °C. It is supplied in the TO-220AB package.

At a glance

• Type: MOSFET
• Max drain–source voltage (V_DS): 400 V
• Max continuous drain current (I_D): 19 A
• Power dissipation (P_D): 180 W
• Max junction temperature (T_J): 150 °C
• Package: TO-220AB

Typical applications

With its 400 V drain–source rating the CS19N40A8H sits in the medium-high-voltage class of switching MOSFETs, typically found in telecom and industrial DC rails, boost and flyback converters, LED and backlight drivers and power-factor-correction stages. Common where the bus sits well above 100 V but below rectified mains.

Gate drive and switching notes

Keep gate–source voltage within the ±30 V maximum; exceeding it punctures the gate oxide and destroys the device permanently.

Switching behaviour is characterised by an output capacitance (C_oss) of 276 pF, which together with the gate drive determines switching loss and the practical upper frequency limit.

Choosing a replacement for the CS19N40A8H

A drop-in substitute for the CS19N40A8H should match its polarity and offer a drain–source rating of at least 400 V and a continuous drain current rating of at least 19 A.

Mechanically, check the replacement against the TO-220AB footprint and confirm the pin order — parts sharing a package outline do not always share a pinout.

Where the application switches inductive loads or runs near the voltage limit, keep extra headroom rather than choosing a part that only just meets the original numbers.

Frequently asked questions

What is the CS19N40A8H?

The CS19N40A8H is a MOSFET (metal-oxide-semiconductor field-effect transistor). It is rated for 400 V drain-source and 19 A continuous drain current.

What is the maximum voltage of the CS19N40A8H?

The CS19N40A8H has a maximum drain-source voltage (Vds) of 400 V. Treat this as an absolute maximum and design with margin, especially when switching inductive loads.

How much current can the CS19N40A8H handle?

It is rated for 19 A of continuous drain current, with power dissipation limited to 180 W. Real-world capability depends on your heatsinking and ambient temperature.

What package does the CS19N40A8H come in?

It is listed in TO-220AB. Verify the pinout of the specific variant, as one outline can carry different pin assignments.

What can I use to replace the CS19N40A8H?

This page lists 17 candidate equivalents matched on electrical ratings and package. Any replacement should meet or exceed the original voltage, current and dissipation figures and use a compatible drive level.