Diodes PAM2304 User Manual

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Description

The PAM2304 is a step-down current-mode, DC-DC converter. At

heavy load, the constant frequency PWM control performs excellent

stability and transient response. To ensure the longest battery life in

portable applications, the PAM2304 provides a power-saving Pulse-

Skipping Modulation (PSM) mode to reduce quiescent current under

light load operation to save power.

The PAM2304 supports a range of input voltages from 2.5V to 5.5V,

allowing the use of a single Li+/Li-polymer cell, multiple Alkaline/NiMH

cell, USB and other standard power sources. The output voltage is

adjustable from 0.6V to the input voltage. All versions employ internal

power switch and synchronous rectifier to minimize external part

count and realize high efficiency. During shutdown, the input is

disconnected from the output and the shutdown current is less than

1µA. Other key features include under-voltage lockout to prevent

deep battery discharge.

The PAM2304 is available in TSOT23-5, TDFN22-8 and TDFN22-6

packages.

Features

 Efficiency up to 95%
 Only 40mA (typ) Quiescent Current
 Output Current: Up to 1A
 Internal Synchronous Rectifier
 3MHz Switching Frequency
 Soft Start
 Under-Voltage Lockout
 Short Circuit Protection
 Thermal Shutdown
 Small TSOT23-5, TDFN22-8 and TDFN22-6 Packages
 RoHS Pass and Green Package

Applications

 Smart Phone
 MID
 Portable Electronics
 Wireless Devices
 Cordless Phone
 Computer Peripherals
 Battery Powered Widgets
 Electronic Scales
 Digital Frame

3MHz, 1A STEP-DOWN DC-DC CONVERTER

Pin Assignments

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PAM2304

PAM2304

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Typical Applications Circuit

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PAM2304

1R







16.0

V

O






2R



Pin Descriptions

Pin

Name

EN 1 8 4

GND 2 — 6 Ground.

SW 3 5, 6 1 The drains of the internalmain and synchronous power MOSFET.

VIN

FB 5 1 3 Feedback voltage to internal error amplifier, the threshold voltage is 0.6V.

AGND — 2 — Analog Ground.

PGND — 4 — Main power ground return pin.

NC — 7 2 Not connected.

TSOT23 TDFN22-8 TDFN22-6

4 3 5 Chip main power supply pin.

Pin Name

Function

Enable Control Input. Force this pin voltage above 1.5V, enables the chip, and below 0.3V
shuts down the device.

Functional Block Diagram

PAM2304

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PAM2304

Absolute Maximum Ratings (@T

These are stress ratings only and functional operation is not implied. Exposure to absolute maximum ratings for prolonged time periods may
affect device reliability. All voltages are with respect to ground

Parameter Rating Unit

Input Voltage -0.3 to +6.0 V

EN, FB Pin Voltage -0.3 to VIN V

SW Pin Voltage -0.3 to (VIN +0.3) V

Junction Temperature 150 °C

Storage Temperature Range -65 to +150 °C

Soldering Temperature 300, 5 sec °C

Recommended Operating Conditions (@T

Parameter Rating Unit

Supply Voltage 2.7 to 5.5 V

Operation Temperature Range -40 to +85

Junction Temperature Range -40 to +125

= +25°C, unless otherwise specified.)

A

= +25°C, unless otherwise specified.)

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°C

Thermal Information

Parameter Symbol Package Max Unit

TSOT23-5 (Note 1) 130

Thermal Resistance (Junction to Case)

Thermal Resistance (Junction to Ambient)

Internal Power Dissipation (TA = +25°C) PD

Note: 1. The maximun output current for TSOT23-5 package is limited by internal power dissipation capacity as
described in Application Information hereinafter.

θ

JC

θ

JA

PAM2304

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TDFN22-8 23.4

TDFN22-6 25

TSOT23-5 250

TDFN22-8 70

TDFN22-6 68

TSOT23-5 400

TDFN22-8 1400

TDFN22-6 980

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°C/W

mW

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PAM2304

Electrical Characteristics (@T

Parameter Symbol Test Conditions Min Typ Max Units

Input Voltage Range

Regulated Feedback Voltage

Reference Voltage Line Regulation

Regulated Output Voltage Accuracy

Peak Inductor Current

Output Voltage Line Regulation LNR

Output Voltage Load Regulation LDR

Quiescent Current

Shutdown Current

Oscillator Frequency

Drain-Source On-State Resistance

SW Leakage Current

High Efficiency η 95 %

EN Threshold High

EN Threshold Low

EN Leakage Current

Over Temperature Protection OTP 150 °C

OTP Hysteresis OTH 30 °C

PAM2304

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= +25°C, VIN = 3.6V, VO = 1.8V, CIN = 10µF, C

A

IN

FB

FB

IO = 100mA

O

VIN = 3V, VFB = 0.5V or VO = 90%

V

= 2.5V to 5V, IO = 10mA

IN

I

= 1mA to 800mA

O

No load 40 70 µA

Q

VEN = 0V

= 100%

V

O

VFB = 0V or VO = 0V

IDS = 100mA

±0.01 1 µA

1.5 V

EH

0.3 V

EL

±0.01 µA

P MOSFET 0.30 0.45 Ω
N MOSFET 0.35 0.50 Ω

V

∆V

f

R

DS(ON)

I

V

V

V

V

I

PK

I

I

SD

OSC

LSW

I

EN

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= 10µF, L = 1µH, unless otherwise specified.)

OUT

2.5 5.5 V

0.588 0.6 0.612 V

0.3 %/V

-3 +3 %

1.5 A

0.2 0.5 %/V

0.5 1.5 %

1 µA

3 MHz

1 MHz

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Typical Performance Characteristics (@T

= +25°C, CIN = 10µF, C

A

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PAM2304

= 10µF, L = 1µH, unless otherwise specified.)

OUT

PAM2304

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