Analog Devices MAX25262 Скачать руководство пользователя страница 2

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2

MAX25262/MAX25263  

Evaluation Kit

Evaluates: MAX25262/MAX25263

Detailed Description of Hardware

The MAX25262 and MAX25263 EV kits provide a 

 

proven layout for the MAX25262 and MAX25263 synchro-

nous buck regulator ICs, respectively. The input voltages 

range from 3.5V to 65V and deliver up to 3A. The EV kits 

can handle an input supply transient up to 70V. Various 

test points are included for evaluation.

External Synchronization

The IC can operate in two modes: forced-PWM (FPWM) 

mode or skip mode. Skip mode has better efficiency for 

light-load conditions. When SYNC is pulled low, the IC 

operates in skip mode for light loads and PWM mode for 

larger loads. When SYNC is pulled high, the IC is forced 

to operate in PWM mode across all load conditions. 

SYNC can be used to synchronize with other supplies if 

a clock source is present. The IC is forced to operate in 

FPWM mode when SYNC is connected to a clock source.

Buck Output Monitoring (PGOOD)

The EV kit provides a power-good output test point 

(PGOOD) to monitor the status of the buck output (OUT). 

PGOOD is high impedance when the output is in regula-

tion. PGOOD goes low when the corresponding regulator 

output voltage drops below 93.5% (typ) of its nominal 

regulation voltage or goes above 108% (typ) of its nomi-

nal regulation voltage.

Programming Buck Output Voltage

The IC can provide a fixed 3.3V/5V output voltage or an 

adjustable  1V  to  20V  output  voltage. To  program  V

OUT 

voltage, place appropriate resistors in positions R5 and 

R6 according to the following equation: 

R5 = R6 (V

OUT

/V

FB

 - 1) 

where typically V

FB 

= 1V (typ) and R6 = 100kΩ.

Spread Spectrum Option

The spread spectrum is pin selectable using the SPS pin. 

Pull the pin high to enable spread spectrum. When spread 

spectrum is enabled, the operating frequency is varied 

±6%, centered at switching frequency. 
The internal spread spectrum is disabled if the devices 

are  synchronized  to  an  external  clock.  However,  the 

devices do not filter the input clock on the FSYNC pin and 

pass any modulation (including spread spectrum) present 

on the driving external clock.

EXTVCC Switchover

The internal linear regulator can be bypassed by connect-

ing an external supply, or the MAX25262/MAX25263 out

-

put to EXTVCC. With valid supply applied to EXTVCC, it 

will be the supply for the internal gate driver. The R

DSON

 

of the FET will increase if the EXTVCC drops below 5V, 

which will reduce the efficiency, therefore approximately 

5V for EXTVCC is recommended for higher efficiency. 

Table 1. Default Jumper Settings

#Denotes RoHS compliant.

Note

: If the output voltage is configured above 5V, please 

ensure the EXTVCC jumper is at position 2-3 to avoid damage 

to the part.

JUMPER

DEFAULT SHUNT 

POSITION

FUNCTIONS

ENABLE

1-2

Buck enabled

PGOOD

Installed

PGOOD TP  

pulled up to bias

SPS

1-2

Spread Spectrum ON

SYNC

1-2

FPWM mode

EXTVCC

1-2

EXTVCC connect  

to OUT

PART

TYPE

MAX25262EVKIT#

EV Kit

MAX25263EVKIT#

EV Kit

Ordering Information

Содержание MAX25262

Страница 1: ...table from 1V to 20V 2A 3A Output Current Capability Frequency Synchronization Input Spread Spectrum Available Voltage Monitoring PGOOD Output Available Proven PCB Layout Fully Assembled and Tested 31...

Страница 2: ...xed 3 3V 5V output voltage or an adjustable 1V to 20V output voltage To program VOUT voltage place appropriate resistors in positions R5 and R6 according to the following equation R5 R6 VOUT VFB 1 whe...

Страница 3: ...04KA01 MURATA 0 1 F CAP SMT 0603 0 1 F 10 100V X7R CERAMIC CHIP C2 C3 C5 C6 C10 C11 08051C105K4Z2A AVX 1 F CAP SMT 0805 1 F 10 100V X7R CERAMIC CHIP C4 EEH ZC1K470P PANASONIC 47 F CAP SMT CASE_G 47 F...

Страница 4: ...30 332ME Coilcraft 3 3 H C13 C14 C16 C18 CGA4J1X7S1E106K125AC TDK 10 F CAP CER 10 F 25V X7S 0805 C15 C17 C19 C20 DO NOT INSTALL MAX25263EVKIT Variant 400kHz 5V REF DES MFG PART MANUFACTURER VALUE DESC...

Страница 5: ...C22 TP_FBR VOUT EXTVCC FB C20 TP_GNDS2 R3 R4 TP_BIAS SYNC C8 SPS FB BIAS VSUP VSUP R5 BIAS ENABLE R1 TP_GNDS L1 L2 C2 VSUP_FILTER C1 GND C4 C5 GND2 TP_GNDS3 C17 C15 C14 C13 L3 C18 C19 C21 OUT C16 TP_...

Страница 6: ...63 Evaluation Kit Evaluates MAX25262 MAX25263 MAX25262 MAX25263 EV Kit PCB Layout Top Silkscreen MAX25262 MAX25263 EV Kit PCB Layout Top Layer MAX25262 MAX25263 EV Kit PCB Layout Internal Layer 2 MAX2...

Страница 7: ...ation Kit Evaluates MAX25262 MAX25263 MAX25262 MAX25263 EV Kit PCB Layout Internal Layer 3 MAX25262 MAX25263 EV Kit PCB Layout Bottom Layer MAX25262 MAX25263 EV Kit PCB Layout Bottom Silkscreen MAX252...

Страница 8: ...other rights of third parties that may result from its use Specifications subject to change without notice No license is granted by implication or otherwise under any patent or patent rights of Analo...

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