Hamradio 73 - Power Supply Design.pdf - zasilacze - militare

POWER SUPPLIES ANALOG

DESIGN GUIDE

•

Data Sheets

Applications Notes

Free Samples

Smallest Dual-Output Supply

for PDAs: Logic Step-Down and

LCD Step-Up

High-Efficiency Hand-Held Supply Fits Internal Switches into a

12-Pin QFN Package

STEPS DOWN TO 1.25V FOR NEWEST LOGIC CHIPS

INPUT

2.0V TO 5.5V

LCD OUTPUT

UP TO 28V

UP TO 10mA

LXLCD

0.1

FBLCD

AIN1

AIN2

MAX1878

LOGIC OUTPUT

1.25V TO V IN

UP TO 500mA

10 µ H

LOGIC

OFF

LCD

ONLCD

OFF

PGND

AGND

PGNDLCD

Packaged in a 0.85mm high, 4mm x 4mm QFN, the MAX1878 is the

simplest and smallest single-chip solution providing both logic and LCD

power for PDAs and hand-held products. For the logic supply, it uses a

high-efficiency (90%) step-down DC-DC converter with synchronous rectifi-

cation that eliminates the need for an external diode, saving cost and size.

For the LCD supply, the internal switch is capable of supplying outputs as

high as 28V. Each output has its own logic-controlled enable.

ANALOG

DESIGN GUIDE

Multiplexers, Switches

Interface Products

Op Amps, Comparators

DC-DC Converters,

Power Supplies

• Dual-Output:

• Step-Down: Logic Supply Down

to 1.25V

• Step-Up: LCD Supply Up to 28V

• Smallest Package: 4mm x 4mm

12-Pin QFN

• Small External Components:

10µF and 10µH

• 90% Efficiency

• Low 19µA Quiescent

Supply Current

• Evaluation Kit

Available to Speed

Designs

• Priced at $1.57 †

P Supervisory

Analog Filters

A/D Converters

Video/High-Speed Amps

D/A Converters

Analog Functions

Voltage References

Temperature Sensors

High-Speed

ADCs & DACs

Signal Conditioners

† 1000-up recommended resale. Price provided is for design guidance and is FOB USA. International prices will differ due to local duties,

taxes, and exchange rates. Not all packages are offered in 1k increments, and some may require minimum order quantities.

Smallest, Highest Efficiency

Multi-Output DC-DC Converter

Compact, Cost-Effective, Integrated Power Supply Solutions for

Digital Cameras and PDAs

Use the MAX1800 step-up master or the MAX1802 step-down master to provide all the voltage

outputs required in your digital camera and PDA designs from a single IC. They include high-effi-

ciency DC-DC converters with synchronous rectifiers to give over 90% efficient power conversion for

the logic supply, which uses >50% of the power in a camera system. They come in a small 32-pin

5mm x 5mm TQFP, which is 40% smaller than existing TQFP solutions. The MAX1800 and MAX1802

also eliminate external components such as power diodes, power switches, and at least one

transformer to save cost and size. For flexibility, add the low-cost, 8-pin SOT23 MAX1801 “slave”

controller to create optional features like a motor control supply for zooming and focusing. The

MAX1800/MAX1802 can provide all the voltages for logic, core, backlighting, LCD, and expansion

port of PDAs.

EXAMPLE OF A COMPLETE DIGITAL CAMERA POWER SUPPLY

(CAN ALSO BE USED IN PDAs)

INPUT

0.7V TO 5.5V

EIGHT OUTPUTS

OUT1

3.3V

LOGIC

1.8V

CORE

LDO

V IN

7.0V

CCFL MODULE

OUT2

V IN

15.0V

MAX1800

CCD BIAS

STEP-UP

MASTER

-7.5V

MAX1800 STEP-UP MASTER

MAX1802 STEP-DOWN MASTER

OUT3

MAX1801 SLAVE CONTROLLER

8-PIN SOT23

2.8mm x 2.9mm

V IN

18.0V

12.0V

32-PIN TQFP—5x5*

7mm x 7mm x 1mm

(DIMENSION INCLUDES LEADS)

LCD BIAS

V IN

OUT4

ZOOM

MOTOR DRIVE

(OPTIONAL)

5.0V

OUT1 ON

OUT2 ON

OUT3 ON

OUT4 ON

LDO ON

MAX1801

OFF

OSC

OSC SLAVE

CONTROLLER

1-, 2-, 3-, or 4-Cell Designs

ADD UP

TO FIVE SLAVE

CONTROLLERS

REF

MAX1800

MAX1802

V IN

GND

Step-Up,

Step-Up/Down

Step-Down

5.0V

LENS COVER

DRIVE

(OPTIONAL)

MAX1801

0.7V to 5.5V Input

2.5V to 11V Input

OSC

SLAVE

CONTROLLER

One Li+,

Two or Three Alkaline

Two Li+,

Four Alkaline

REF

Internal Step-Up,

Three Step-Up Controllers,

LDO Controller

Step-Down Controller,

Three Step-Up Controllers,

Internal Step-Down

*Dimensions include 5mm body plus 1mm for the length of each lead for a total of 7mm.

Lowest Cost Three- and Five-Output

xDSL and Cable Modem Power Supplies

High-Efficiency Step-Down Controller Plus Multiple LDO Controllers

on a Single IC

COMPLETE, LOW-COST, FIVE-OUTPUT xDSL MODEM SUPPLY

• No Current-Sense

Resistors Mean

Less Cost

• Step-Down Output:

1.25V to 5.5V

• LDO Outputs:

±1.25V to ±15V

• Power-OK Checks All

Outputs

• EV Kit Available to

Speed Designs

INPUT

LOW-COST

ADAPTER

4.5V TO 28V

FIVE OUTPUTS

V+

3.3V

I/O

2.5V

500mA

CORE

LDO1

100mA

AFE

MAX1865T

LDO2

12V

100mA

POSITIVE

LINE DRIVER

LDO3

-12V

100mA

NEGATIVE

LINE DRIVER

LDO4

POK

POWER OK

SIGNAL

GND

Use the MAX1864 and MAX1865 power-supply controller ICs to build the lowest cost xDSL and

cable modem consumer premises equipment (CPE) power supplies. They integrate a high-efficiency

step-down DC-DC controller and two to four linear regulator controllers that provide all the required

voltages for CPE. The current-mode step-down controller uses an external, dual N-channel MOSFET to

provide low-cost synchronous rectification for high efficiency and low heat. To further save cost, no

external current-sense resistor is required. Switching frequencies of 100kHz and 200kHz permit the

use of low-cost magnetics and aluminum electrolytic capacitors. The linear regulator controllers drive

inexpensive external bipolar junction transistors (B JTs).

MAX1864

• Step-Down Controller

• Two Positive LDO Controllers

• 16-Pin QSOP Package

MAX1865

• Step-Down Controller

• Three Positive LDO Controllers

• One Negative LDO Controller

• 20-Pin QSOP Package

110V Power Supply Controller

Integrates High-Voltage Startup FET

• Up to 300kHz Operation for Smaller

Magnetics and Capacitors

• Wide 11V to 110V Input Voltage Range

• Guaranteed ±2.5% V REF Accuracy

• Only 2.2mA Supply Current

• Input Feed-Forward

Compensation for Fast Line-

Transient Response

• Programmable: Current

Limit, Maximum Duty

Cycle, Oscillator

Frequency, Undervoltage

Lockout, and Soft-Start

• External Frequency Synchronization

• MAX5003 EV Kit Available to Speed

Designs

Optimized for Telecom and

Data Communications Applications

V IN (UP TO 110V)

V OUT

V CC

V IN

N_DRV

R SENSE

MAX5003

43% SMALLER FOOTPRINT

THAN COMPETITOR’S SO-14

HV PWM

CONTROLLER

INTERNAL

110V STARTUP

TRANSISTOR

OPTOCOUPLER

FEEDBACK

ISOLATION

Low-Cost, Dual-Output SLIC Supply

Uses Standard Transformer

STANDARD TRANSFORMER FROM

MULTIPLE VENDORS

REDUCES COST

OUTPUT VOLTAGE CAN BE SET

TO OPTIMIZE SHORT-LOOP OR

LONG-LOOP OPERATION WITH

VARIOUS SLIC ICs

OUTPUT 1

-72V, 100mA RING BATTERY

INPUT

8V TO 24V

V CC

OUTPUT 2

-24V, 400mA T ALK BATTERY

LOW-COST

UNREGULATED

AC-DC

ADAPTER

MAX1856

SYNC

SYNC SIGNAL

(OPTIONAL)

FLYBACK TOPOLOGY REDUCES

INPUT RIPPLE CURRENT

FREQ

EXT

GND

FREQUENCY

SELECT

(100kHz TO 500kHz)

DIGITAL

SOFT-START

EVALUATION KIT AVAILABLE TO SPEED DESIGNS . The MAX1856 can be configured to work with different input and

output voltages from those shown in this block diagram. For further information, please contact your local Maxim FAE or email us

at powerhelp@design.mxim.com.

Industry’s First Hot-Swap Switches

for Power-Over-LAN

Simple-Swappers™ Require No Design and No External Components

65V SWITCH IS IEEE802.3af COMPATIBLE

DATA TERMINAL EQUIPMENT

• IP Phone

• Wireless LAN Access Node

(Eliminates AC Adapter)

MAX5910

MAX5917

BACKPLANE

(+10V TO +65V)

V IN

V OUT

UVLO

GND

•

Security Camera

(Eliminates AC Adapter)

ENABLE

FAULT

SAFELY CONNECT YOUR

DATA TERMINAL EQUIPMENT

TO A SWITCH/ROUTER

POWER SOURCE.

N.C.

PGOOD

Beats Competition 3 Ways

1) First IEEE802.3af-Compatible

Hot-Swap Switch

• Drives 500µF at Startup

• 500mA Output Current at

Startup

• Input Voltage Range:

+10V to +65V

2) Highest Integration

• Internal Switch Delivers 26W

of Power

• Built-In Undervoltage Lockout

(UVLO)

• Power Good Output Monitors:

UVLO, Power Not Good, and

Thermal Shutdown

3) Smallest Board Space and

Lowest Cost

• Requires No External

Components

• 60% Less Board Space than

Discrete Solutions

• 8-Pin or 16-Pin SO Packages

-48V SWITCH DELIVERS POWER AND DATA OVER

STANDARD CATEGORY 5 CABLE

MONITORS UVLO

POWER NOT GOOD,

LOAD DISCONNECT

& THERMAL SHUTDOWN

WITHSTANDS

-70V TRANSIENTS

♦

INTERNAL POWER

SWITCH

Ω

♦

DELIVERS 13W POWER

(20W FOR MAX5912)

♦

DISCONNECTS LOAD AT

“ZERO CURRENT”

-16V to -65V

FAULT OUTPUT

ON/OFF

V IN

GATE

V OUT

AGND

COMPATIBLE WITH

3.3V AND 5V LOGIC

♦

SAFE HOT SWAP

MAX5911/

MAX5912

SIMPLE

SWAPPER™

UVLO

DGND

ADJUST DEFAULT

UVLO THRESHOLD

WITH EXTERNAL

RESISTOR DIVIDER

WITH RESPECT

TO AGND

CAN VARY

Output Current Limit

(mA)

280

Part

Pin-Package

MAX5910

8-SO

MAX5911

280

8-SO

MAX5912

415

16-SO

MAX5917A

MAX5917B

567

420

16-SO

Simple-Swapper is a trademark of Maxim Integrated Products, Inc.

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