FS5502 datasheet(65/113 Pages) NXP

65 / 113 page

NXP Semiconductors

FS5502

High voltage PMIC with multiple SMPS and LDO

Current (A)

BUCK1 Efficiency (VPRE = 4.1 V)

aaa-035374

Efficiency

(%)

0.8 V_Eff

1.25 V_Eff

1.8 V_Eff

Cin

Ext. C and L

Int. MOSFET's

µF

ESR Cin

mΩ

Cout

µF

ESR Cout

mΩ

L coil

µH

DCR coil

mΩ

HS_Rdson

135

mΩ

QLS

0.5

QHS

0.5

THS_sw

GLS_drive

GHS_drive

LS_Rdson

mΩ

TLS_sw

2.5

2.0

1.0

1.5

0.5

2.25

1.75

0.75

1.25

0.25

100

Figure 17. BUCK1 theoretical efficiency

16 Low voltage buck: BUCK3

16.1 Functional description

BUCK3 block is a low voltage, synchronous, peak current mode buck converter with

integrated HS PMOS and LS NMOS. BUCK3 works in force PWM and the output voltage

is configurable by OTP from 1.0 V to 3.3 V, the switching frequency is 2.22 MHz and the

output current is limited to 3.6 A peak. The input of this block can be connected to the

output of VPRE. The stability is ensured by an internal Type 2 compensation network

with slope compensation.

By default, BUCK3 switching frequency is derived from the internal oscillator, and can

be synchronized with an external frequency signal applied on FIN input pin. The change

from internal oscillator to external clock or vice versa is controlled by I2C.

An overcurrent detection and a thermal shutdown are implemented on BUCK3 to protect

the internal MOSFETs. The overcurrent induces a duty cycle reduction that could lead to

the output voltage gradually dropping, causing an undervoltage condition.

BUCK3 is part number dependent according to OTP_BUCK3EN bit. BUCK3_INQ pin,

used to bias internal BUCK3 driver, and must be connected to the same source pin as

BUCK3_IN pin. The ramp up and ramp down of BUCK3 when it is enabled and disabled

is configurable with OTP_DVS_BUCK3[1:0] bits to accommodate multiple MCU soft start

requirements.

Programmable phase shift control is implemented, see Section 18 "Clock management".

FS5502

All information provided in this document is subject to legal disclaimers.

Product data sheet

Rev. 4 — 27 October 2021

65 / 113

FS5502 Datasheet(PDF) 65 Page - NXP Semiconductors

FS5502 Datasheet(HTML) 65 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL