MIC2132 datasheet(36/48 Pages) MICROCHIP

36 / 48 page

MIC2132

DS20006654B-page 36

 2022 Microchip Technology Inc. and its subsidiaries

The output voltage is determined by Equation 5-37.

EQUATION 5-37:

A typical value of R1 can be between 3 kΩ and 10 kΩ.

If R1 is too large, it may allow noise to be introduced

into the voltage feedback loop. If R1 is too small, it

decreases the efficiency of the buck converter,

especially at light loads. After R1 is selected, R2 can be

calculated using the formula found in Equation 5-38.

EQUATION 5-38:

5.7

AVP Droop Load Line Resistance

The AVP droop load line resistance can be calculated

using Equation 5-39.

EQUATION 5-39:

5.8

Power Dissipation in MIC2132

The MIC2132 features two Low-Dropout (LDO)

regulators to supply power at the PVDD pin from either

VIN or EXTVDD, depending on the voltage at the

EXTVDD pin. PVDD powers the MOSFET drivers and

the VDD pin powers the internal circuitry and is

recommended to connect to PVDD through a low-pass

filter. In the applications where the output voltage is 5V

and above (up to 14V), it is recommended to connect

EXTVDD to the output to reduce the power dissipation

in the MIC2132, in order to reduce the MIC2132

junction temperature and to improve system efficiency.

The power dissipation in the MIC2132 depends on the

internal LDO being in use, gate charge of the external

MOSFETs and switching frequency. The power

dissipation and the junction temperature of the

MIC2132 can be estimated using Equation 5-40,

Equation 5-41 and Equation 5-42.

Power dissipation in the MIC2132 is calculated in

Equation 5-40 when EXTVDD is not used.

EQUATION 5-40:

Power dissipation in the MIC2132 is calculated in

Equation 5-41 when EXTVDD is used.

EQUATION 5-41:

The junction temperature of the MIC2132 can be

estimated using Equation 5-42.

EQUATION 5-42:

Where:

VREF =0.6V

VOUT = VREF ×1 +









R2 =

VREF × R1

VOUT – VREF

Where:

∆VOUT(DROOP) = Change in Output Voltage with Load

∆IL(PK) = Total Change in Peak Inductor

Current for All Phases for a Given

Change in Load Current

RSENSE = Current Sense Resistance

VREF = Reference Voltage (0.6V typical)

VOUT = Output Voltage

RDROOP = Resistance of Droop Setting Resistor

Connected at the DROOP Pin

RFBB2 = Lower Bottom Feedback Resistance

Value

RLOADLINE =

VOUT(DROOP)

IL(PK)

VREF

VOUT









 × RSENSE

RDROOP

RFBB2

1 +

× 1 –

VREF

VOUT

Where:

IG(TOTAL) = Total Average Gate Drive Current for

All Phases

IQ = Quiescent Current of MIC2132

QG(HS1), QG(LS1) = Gate Charge of High-Side and

Low-Side MOSFETs in Phase 1

QG(HS2), QG(LS2) = Gate Charge of High-Side and

Low-Side MOSFETs in Phase 2

PIC = VIN × (IG(TOTAL) + IQ)

IG(TOTAL) = (QG(HS1) × QG(LS1) + QG(HS2) + QG(LS2))fSW

Where:

VEXTVDD = Voltage at EXTVDD Pin

(4.7V ≤ VEXTVDD ≤ 14V typically)

IG(TOTAL) = Total Average Gate Drive Current for All

Phases

IQ = Quiescent Current of MIC2132

PIC = VEXTVDD × (IG(TOTAL) + IQ)

Where:

TJ = Junction Temperature of MIC2132

TA = Ambient Temperature

PIC = Power Dissipation of MIC2132

JA = Junction-to-Ambient Thermal Resistance of

MIC2132 (34°C/W typical)

TJ = PIC × JA + TA

MIC2132 数据表(PDF) 36 Page - Microchip Technology

MIC2132 数据表(HTML) 36 Page - Microchip Technology

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

数据表下载

链接网址

MIC2132 数据表(PDF) 36 Page - Microchip Technology

MIC2132 数据表(HTML) 36 Page - Microchip Technology

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

数据表 下载

链接网址

数据表下载