Processor Power Supply Requirements

Power Supply Requirements

Power Pin

Minimum Voltage (V)

Typical Voltage (V)

Maximum Voltage (V)

Maximum Current (mA)

Description

VBUS

4.5

5.0

5.5

500

VBUS power input

VBAT

3.5

-

4.6

500

VBAT power output

VCC

3.2

-

4.7

500

System power input

VSYS

-

3.3

-

500

VSYS power output(1)

BUCK_LX

-

1.25

-

50

BUCK output pin, connected to an inductor

BUCK_FB

-

1.25

-

50

BUCK feedback and internal power input pin, connected to the other end of the inductor with an external capacitor

VDD_VOUT1

-

1.1

-

50

Internal LDO with external capacitor

VDD_VOUT2

-

0.9

-

20

Internal LDO with external capacitor

VDD_RET

-

0.9

-

1

Internal LDO with external capacitor

VDD_RTC

-

1.1

-

1

Internal LDO with external capacitor

VDD18_VOUT

-

1.8

-

30

SIP power(2)

VDD33_VOUT1

-

3.3

-

150

3.3V LDO output 1(3)

VDD33_VOUT2

-

3.3

-

150

3.3V LDO output 2

AVDD33_AUD

2.97

3.3

3.63

50

3.3V audio power input

AVDD_BRF

2.97

3.3

3.63

100

RF power input

GPADC_VREF

-

-

-

-

GPADC reference voltage input; connect only an external 4.7uF capacitor, with no external power supply

AUD_VREF

-

-

-

-

Audio reference voltage input; connect only an external 1.0uF capacitor, with no external power supply

MIC_BIAS

1.4

-

2.8

-

MIC power output

Note

(1) VSYS power supply, powering AVDD_BRF

(2) VDD18_VOUT power supply
SF32LB520U36, externally supplied 3.3V power
SF32LB523UB6, SF32LB525UC6, and SF32LB527UD6 use the internal LDO and do not require an external power supply

(3) VDD33_VOUT1 power supply
SF32LB520U36, powering VDD18_VOUT, external Flash, and AVDD33_AUD
SF32LB523UB6, SF32LB525UC6, and SF32LB527UD6 power the external Flash and AVDD33_AUD