DIO6905

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DIO6905 • Rev. 1.8

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Figure 16. Operation blocks in sleep mode

Figure 17. FB Average voltage in sleep mode

Enable (EN)

When the input voltage is greater than the undervoltage lockout (UVLO) threshold (typically 2.1 V), the DIO6905

can be enabled by pulling EN higher than 1.2 V. Leaving EN floating or pulling it down to ground disables the

DIO6905. There is an internal 1 MΩ resistor from EN to ground.

When the DIO6905 is disabled, the part goes into output discharge mode automatically. The internal discharge

MOSFET provides a resistive discharge path for the output capacitor.

Soft-start

The DIO6905 has a built-in soft-start that ramps up the output voltage at a constant slew rate that avoids

overshooting at startup. The soft-start time is typically approximately 0.6 ms.

Current limit

The DIO6905 has a 2.4 A current limit for the HS-FET. When the HS-FET hits its current limit, the DIO6905

enters current limit mode until the current drops to prevent the inductor current from rising and possibly damaging

the components.

Short-circuit protection and recovery

The DIO6905 enters short-circuit protection (SCP) mode when it reaches the current limit and attempts to

recover from the short-circuit by entering hiccup mode. In SCP, the DIO6905 disables the output power stage,

discharges the soft-start capacitor, and then enacts a soft-start procedure. If the short-circuit condition still holds

after the soft-start ends, the DIO6905 repeats this cycle until the short-circuit disappears and the output rises

back to regulation levels.