Rainbow-electronics MAX1847 Uživatelský manuál stáhnout pdf

General Description

MAX1846/MAX1847 high-efficiency PWM inverting con-

trollers allow designers to implement compact, low-

noise, negative-output DC-DC converters for telecom

and networking applications. Both devices operate

from +3V to +16.5V input and generate -2V to -200V

output. To minimize switching noise, both devices fea-

ture a current-mode, constant-frequency PWM control

scheme. The operating frequency can be set from

100kHz to 500kHz through a resistor.

The MAX1846 is available in an ultra-compact 10-pin

µMAX package. Operation at high frequency, compati-

bility with ceramic capacitors, and inverting topology

without transformers allow for a compact design.

Compatibility with electrolytic capacitors and flexibility

to operate down to 100kHz allow users to minimize the

cost of external components. The high-current output

drivers are designed to drive a P-channel MOSFET and

allow the converter to deliver up to 30W.

The MAX1847 features clock synchronization and shut-

down functions. The MAX1847 can also be configured

to operate as an inverting flyback controller with an N-

channel MOSFET and a transformer to deliver up to

70W. The MAX1847 is available in a 16-pin QSOP

package.

Current-mode control simplifies compensation and pro-

vides good transient response. Accurate current-mode

control and over current protection are achieved

through low-side current sensing.

Applications

Cellular Base Stations

Networking Equipment

Optical Networking Equipment

SLIC Supplies

CO DSL Line Driver Supplies

Industrial Power Supplies

Automotive Electronic Power Supplies

Servers

Features

♦ 90% Efficiency

♦ +3.0V to +16.5V Input Range

♦ -2V to -200V Output

♦ Drives High-Side P-Channel MOSFET

♦ 100kHz to 500kHz Switching Frequency

♦ Current-Mode, PWM Control

♦ Internal Soft-Start

♦ Electrolytic or Ceramic Output Capacitor

♦ The MAX1847 also offers:

Synchronization to External Clock

Shutdown

N-Channel Inverting Flyback Option

MAX1846/MAX1847

High-Efficiency, Current-Mode,

Inverting PWM Controller

________________________________________________________________ Maxim Integrated Products 1

MAX1846

MAX1847

VL IN

COMP

FREQ

REF

GND

PGND

EXT

POSITIVE

NEGATIVE

OUT

Typical Operating Circuit

19-2091; Rev 0; 8/01

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Ordering Information

PART TEMP. RANGE PIN-PACKAGE

MAX1846EUB -40°C to +85°C 10 µMAX

MAX1847EEE -40°C to +85°C 16 QSOP

Pin Configurations appear at end of data sheet.

1 2 3 4 5 6 ... 19 20

Shrnutí obsahu

Strany 1 - Inverting PWM Controller

General DescriptionMAX1846/MAX1847 high-efficiency PWM inverting con-trollers allow designers to implement compact, low-noise, negative-output DC-DC c

Strany 2

MAX1846/MAX1847High-Efficiency, Current-Mode, Inverting PWM Controller10 _____________________________________________________________________________

Strany 3