MAX1947ETAXY-T Просмотр технического описания (PDF) - Maxim Integrated

Номер в каталоге

Компоненты Описание

производитель

MAX1947ETAXY-T

Low Input/Output Voltage Step-Up DC-DC Converter with RESET

Maxim Integrated 

Low Input/Output Voltage

Step-Up DC-DC Converter with RESET

Typical Operating Characteristics (continued)

(VIN = 1.5V, Circuit of Typical Application Circuit, TA = +25°C, unless otherwise noted.)

POWER-ON RESET WAVEFORMS

MAX1947toc17

EXITING AND ENTERING

SHUTDOWN WAVEFORMS

MAX1947toc18

VIN

VRESET

1V/div

1V/div

VOUT

VRESET

1V/div

1V/div

VOUT

20ms/div

1V/div

VSHDN

20ms/div

1V/div

Pin Description

PIN

NAME

FUNCTION

Active-Low Push-Pull Reset Output. RESET goes high 75ms (min) after the output voltage has

1

RESET exceeded 90% of its final value. The RESET output is valid for output voltages as low as 0.9V. RESET

is driven low in shutdown.

2

GND

Ground. Connect to exposed paddle.

3

GND

Ground. Connect to exposed paddle.

4

SHDN

Shutdown Input. Connect to BATT or logic 1 for normal operation. Connect to GND or logic 0 for a low

quiescent-current shutdown mode.

5

PGND Power Ground. Connect to exposed paddle.

6

LX

Inductor Connection to the Drains of the Internal n-Channel Switch and p-Channel Synchronous

Rectifier

7

OUT

Regulator Output. Bypass with 10µF ceramic capacitor to GND for full-load capability. For less than

50% of full load, a 4.7µF capacitor can be used.

8

BATT

Battery Connection. VBATT is used for the startup oscillator and to power the chip when VOUT < VBATT.

—

EP

Exposed Paddle. Connect to GND and PGND.

Detailed Description

The MAX1947 compact step-up DC-DC converter starts

up with voltages as low as 0.8V and operates with input

voltages down to 0.7V. An internal synchronous rectifier

reduces cost by eliminating the need for an external

Schottky diode and improves overall efficiency by

reducing losses in the circuit. The efficiency is further

increased with the low 70µA quiescent current and low

on-resistance of the internal n-channel MOSFET power

switch. The MAX1947 uses Maxim’s proprietary True

Shutdown circuitry, which disconnects the output from

the input in shutdown and actively discharges the

output to ground.

6 _______________________________________________________________________________________

Share Link: