ACT41000 datasheet(29/72 Pages) QORVO

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ACT41000

Programmable Voltage, Programmable Current, Low Noise

RFPoL Step-Down Voltage Regulator

Auxiliary LDO

For the purpose of supporting one another small power rail, the ACT41000 integrates an auxiliary 20 mA LDO. This AUX

LDO is powered by the V5V pin and its output voltage is regulated at the VO(VLDO) target.

Between the VLDO pin and the GND5V pin, an AUX LDO Output Capacitors is required.

Figure 50. AUX LDO Regulator

AUX LDO Enable

The AUX LDO is activated automatically when the V5V pin voltage exceeds the VIT(V5V) threshold. See Mini-buck Regulator.

In case of application where this power rail is not needed, the AUX LDO can be disabled by setting the I

2C Reg09[0] to

logic-L to save power.

AUX LDO Soft-start

To avoid a big inrush current, the AUX LDO execute a soft-start procedure. This soft-start sweeps its reference voltage from

0% to 100% in the tSS(LDO) target period.

AUX LDO Power-Good

There is a comparator monitoring the VLDO pin voltage. The output signal from this comparator is device internal. This

comparator does trigger no event in the Control Logic state-machine "main" sequence flow but, once the AUX LDO is

activated, it can trigger an "error" flow after the AUX LDO Soft-start operation completed.

AUX LDO Output Voltage Programming

The output voltage of the AUX LDO is programmable from 0.9 V to 4.05 V in 50 mV step by the I

2C Reg0D[5:0].

See Table 26 for a target code to program and this table is calculated by the Eq.(1).

(1)

It’s default value is stored in the Factory Programmed ROM.

See Factory Programming Options.

AUX LDO Over-Current Protection

The over-current protection (OCP) limits its output current not to exceed the IOCP(VLDO) threshold. When it exceeds, the

AUX LDO reduces the output current in a fold-back manner. Because of this fold-back current action, the VLDO pin voltage

eventually decreases to hit AUX LDO Under-Voltage Protection.

AUX LDO Under-Voltage Protection

The under-voltage protection (UVP) monitors the VLDO pin voltage at the VUVP(VLDO) threshold. For any reason, it falls

below the threshold, the device triggers the under-voltage protection.

See Executing Protections for the execution of this protection.

ACT41000 Data Sheet, Rev. B, 01-Apr-2022

Subject to change without notice

ACT41000 Datasheet(PDF) 29 Page - Qorvo, Inc