MP92265

– 18V, 5A, SYNCHRONOUS, STEP-DOWN CONVERTER

MP92265 Rev. 1.0

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11

11/29/2016

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reduced greatly to alleviate thermal issues and

to protect the regulator. The MP92265 exits

hiccup mode once the over-current condition is

removed.

Thermal Shutdown

Thermal shutdown prevents the chip from

operating at exceedingly high temperatures.

When the temperature of the silicon reaches

150°C, the entire chip shuts down. When the

temperature

is

below

its

lower

threshold

(typically 130°C), the chip is enabled again.

Floating Driver and Bootstrap Charging

An external bootstrap capacitor powers the

floating power MOSFET driver. This floating

driver has its own UVLO protection. This

UVLO’s rising threshold is 2.6V with a

hysteresis of 350mV. The bootstrap capacitor

5V BST voltage across C4.

Figure 3: Internal Bootstrap Charging Circuit

Start-Up and Shutdown

The reference block starts first, generating a

stable reference voltage, and then the internal

regulator is enabled. The regulator provides a

stable supply for the remaining circuitries.

thermal shutdown. In the shutdown procedure,

the signaling path is blocked first to avoid any

rail are then pulled down. The floating driver is

not subject to this shutdown command.