Rainbow Electronics MAX1595 User Manual

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1

2

3

4

8

7

6

5

OUT

CXP

CXN

PGNDGND

IN

SHDN

AOUT

MAX1595

µMAX

TOP VIEW

OUTPUT

OUT

IN

INPUT

SHDN

GND

CXN CXP

PGND

AOUT

MAX1595

MAX1595

Regulated 3.3V/5.0V Step-Up/Step-Down

Charge Pump

Maxim Integrated Products 1

Typical Operating Circuit

19-2107; Rev 1; 8/02

General Description

The MAX1595 charge-pump regulator generates either

3.3V or 5V from a 1.8V to 5.5V input. The unique control
architecture allows the regulator to step up or step
down the input voltage to maintain output regulation.
The 1MHz switching frequency, combined with a
unique control scheme, allows the use of a ceramic
capacitor as small as 1µF for 125mA of output current.
The complete regulator requires three external capaci­tors—no inductor is needed. The MAX1595 is specifi­cally designed to serve as a high-power, high­efficiency auxiliary supply in applications that demand
a compact design. The MAX1595 is offered in space­saving 8-pin µMAX and high-power 12-pin thin QFN
packages.

Applications

White LED Power

Flash Memory Supplies

Battery-Powered Applications

Miniature Equipment

PCMCIA Cards

3.3V to 5V Local Conversion Applications

Backup-Battery Boost Converters

3V to 5V GSM SIMM Cards

Features

♦ Ultra-Small: Requires Only Three Ceramic

Capacitors

♦ No Inductors Required

♦ Up to 125mA Output Current

♦ Regulated ±3% Output Voltage

♦ 1MHz Switching Frequency

♦ 1.8V to 5.5V Input Voltage

♦ 220µA Quiescent Current

♦ 0.1µA Shutdown Current

♦ Load Disconnect in Shutdown

Ordering Information

Pin Configurations continued at end of data sheet.

Selector Guide

*Contact factory for other fixed-output voltages from 2.7V to 5.0V.

Pin Configurations

PART TEMP RANGE PIN-PACKAGE

MAX1595EUA33 -40°C to +85°C
MAX1595ETC33

MAX1595EUA50

MAX1595ETC50

PART V

MAX1595EUA33 3.3V
MAX1595ETC33

MAX1595EUA50

MAX1595ETC50

8 µMAX

-40°C to +85°C

-40°C to +85°C

-40°C to +85°C

* TOP M ARK

OUT

3.3V

5.0V

5.0V

12 Thin QFN

8 µMAX

12 Thin QFN

AAAP

AAAM

—

—

MAX1595

Regulated 3.3V/5.0V Step-Up/Step-Down
Charge Pump

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VIN= 2V for MAX1595_ _ _33, VIN= 3V for MAX1595_ _ _50, CIN= 1µF, CX= 0.22µF, C

OUT

= 1µF, TA= -40° to +85°C, unless otherwise

noted. Typical values are at T

A

= +25°C.) (Note 1)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

IN, OUT, AOUT to GND............................................-0.3V to +6V

SHDN to PGND ........................................................-0.3V to +6V

PGND to GND .......................................................-0.3V to +0.3V

CXN to PGND.....................-0.3V to (Lower of IN + 0.8V or 6.3V)

CXP to GND ................................-0.8V to (Higher of OUT + 0.8V

or IN + 0.8V but not greater than 6V)

Continuous Output Current ...............................................150mA

Continuous Power Dissipation (T

A

= +70°C)

8-Pin µMAX (derate 4.5mW/°C above +70°C) ............362mW

12-Pin Thin QFN (derate 18.5mW/°C

above +70°C)............................................................1481mW

Operating Temperature Range ...........................-40°C to +85°C

Junction Temperature......................................................+150°C

Storage Temperature Range .............................-65°C to +150°C

Lead Temperature (soldering, 10s) .................................+300°C

Note 1: Specifications to -40°C are guaranteed by design, not production tested.

Input Voltage Range V

Input Undervoltage Lockout
Threshold

Input Undervoltage Lockout
Hysteresis

Output Voltage V

No-Load Input Current I

Switching Frequency f

Shutdown Supply Current I

SHDN Input Voltage Low V
SHDN Input Voltage High V
SHDN Input Leakage Current 0.1 µA

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

IN

OUT

Q

OSC

SHDN

IN L

IN H

0 < I
V

0 < I
= +2.0V

0 < I
= +1.8V

VIN = +2.0V, MAX1595_ _ _33 220 320

VIN = +3.0V, MAX1595_ _ _50 240 350

I

L OA D

SHDN = 0, VIN = +5.5V, V

VIN = 2.0V to 5.5V 0.6 V

VIN = 2.0V to 5.5V 1.6 V

L OA D

= + 3.0V

I N

LOAD

LOAD

> 20m A, V

< 125m A,

< 75mA, V

< 30mA, V

OU T

TA = 0 to +85°C 4.85 5.05 5.15

T

= -40°C to +85°C 4.80 5.20

A

TA = 0 to +85°C 3.20 3.33 3.40

IN

= -40°C to +85°C 3.16 3.44

T

A

TA = 0 to +85°C 3.20 3.33 3.40

IN

= -40°C to +85°C 3.16 3.44

T

A

> V

IN

= 0 5 µA

OUT

1.8 5.5 V

1.40 1.60 1.72 V

40 mV

0.85 1.0 1.15 MHz

V

µA

MAX1595

Regulated 3.3V/5.0V Step-Up/Step-Down

Charge Pump

_______________________________________________________________________________________ 3

__________________________________________Typical Operating Characteristics

(Circuit of Figure 4, VIN= 2V for MAX1595_ _ _33, VIN= 3V for MAX1595_ _ _50, TA = +25°C, unless otherwise noted.)

0.1

10

1

1000

100

10000

021345

NO LOAD SUPPLY CURRENT

vs. SUPPLY VOLTAGE

MAX1595 toc01

SUPPLY VOLTAGE (V)

SUPPLY CURRENT (µA)

6

V

OUT

= 5V

200ns/div

OUTPUT WAVEFORM

50mV/div

MAX1595 toc02

OUTPUT WAVEFORM. AC-COUPLED.
V

IN

= 3.6V, I

LOAD

= 100mA, C

OUT

= 1µF

V

OUT

= 5V

4.90

5.00

4.98

4.96

4.94

4.92

5.06

1 10 100

1000

OUTPUT VOLTAGE

vs. LOAD CURRENT

MAX1595 toc03

LOAD CURRENT (mA)

OUTPUT VOLTAGE (V)

5.04

5.02

VIN = 3V

VIN = 3.6V

VIN = 3.3V

V

OUT

= 5V

100

0

1 10 100

3V EFFICIENCY

vs. LOAD CURRENT

20

10

MAX1595 toc04

LOAD CURRENT (mA)

EFFICIENCY (%)

40

30

60

70

50

80

90

VIN = 1.8V

VIN = 2.4V

2ms/div

LINE-TRANSIENT RESPONSE

MAX1595 toc07

A: INPUT VOLTAGE: VIN = 3.1V TO 3.6V, 500mV/div
B: OUTPUT VOLTAGE: I

LOAD

= 50mA, 100mV/div

A

B

100

0

0.1 1 10 100 1000

5V EFFICIENCY

vs. LOAD CURRENT

20

MAX1595 toc05

LOAD CURRENT (mA)

EFFICEINCY (%)

40

60

80

70

50

30

10

90

VIN = 3.6V

VIN = 3.3V

VIN = 3V

100µs/div

SHUTDOWN TIMING

MAX1595 toc06

A: OUTPUT VOLTAGE: RL = 100Ω, 2V/div
B: SHDN VOLTAGE: 2V/div

A5V

B

200µs/div

LOAD-TRANSIENT RESPONSE

MAX1595 toc08

A: LOAD CURRENT: I

LOAD

= 5mA to 95mA, 100mA/div

B: OUTPUT VOLTAGE: AC-COUPLED 100mV/div

A

B

C

OUT

= 1µF

1

0

2

4

3

5

6

021

3

4

5

6

OUTPUT VOLTAGE

vs. SUPPLY VOLTAGE

MAX1595 toc09

SUPPLY VOLTAGE (V)

OUTPUT VOLTAGE (V)

V

OUT

= 5V, I

LOAD

= 125mA

V

OUT

= 3.3V, I

LOAD

= 75mA