US-based semiconductor supplier Diodes has introduced its AP74502Q and AP74502HQ automotive-compliant 80 V ideal diode controllers, providing protection against reverse connections and voltage transients in applications such as advanced driver assistance systems (ADAS), body control modules, infotainment systems, exterior lighting and USB charging ports.

The ideal diode controllers have the features required to implement an efficient and fast reverse polarity protection circuit. They also include a load disconnect function in case of overvoltage and undervoltage events.

The 80 V capability is suitable for all 12 V and 24 V batteries in hybrid and electric vehicles, as well as the emerging 48 V systems.

The shift to 48 V is paving the way for various EV innovations, enabling features like electric turbocharging and improved regenerative braking. The higher voltage also facilitates advanced infotainment systems and electrified auxiliary components. It could also lead to a zonal architecture, allowing more efficient power distribution and reduced wiring needs. The ±80 V rating is particularly relevant for the stricter overvoltage stress conditions associated with these 48 V systems, according to the company.

Unlike ideal diodes with reverse current blocking features, these devices are suitable for applications where energy may return to the input supply. However, they can also be configured as surge stoppers to protect overvoltage supply and downstream loads against unsuppressed load dump transients.

The AP74502Q and AP74502HQ controllers also support input voltages as low as 3.2 V, ensuring correct and reliable operation even during severe cold crank conditions, which can cause the battery voltage to drop significantly. Both devices share a peak gate turn-off sink current of 2.3 A, enabling rapid turn-off of the external N-channel MOSFETs when required, for example, during overvoltage or undervoltage events.

When the charge pump is enabled, the operating quiescent current (IQ) is 62µA, and 1µA in disabled mode. This minimizes the overall power consumption of the system and reduces battery drain to an absolute minimum.

The AP74502Q features a peak gate source current, typically 60 μA, which provides a smooth start-up with inherent inrush current control, for applications where limiting the initial current surge is important. The AP74502HQ boasts a higher 11 mA peak gate source current, similar to earlier members of the company’s ideal diode controller portfolio. This stronger gate drive allows for a faster turn-on of the external MOSFET, within 1 µs.

The AP74502Q and AP74502HQ are available in the industry-standard SOT28 package with an operating temperature range from -40° C to 125° C.

Source: Diodes