PAM2305AAB280

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PAM2305 Document number: DSxxxxx Rev. 2 - 6 1 of 17 www.diodes.com January 2013 © Diodes Incorporated PAM2305 A Product Line of Diodes Incorporated 1A STEP-DOWN DC-DC CONVERTER Description The PAM2305 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 PAM2305 provides a power-saving Pulse- Skipping Modulation (PSM) mode to reduce quiescent current under light load operation to save power. The PAM2305 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, while the part number suffix PAM2305-XX indicates pre-set output voltage of 3.3V, 2.8V, 2.5V, 1.8V, 1.5V, 1.2V or adjustable. 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 0.1µA. Other key features include under-voltage lockout to prevent deep battery discharge. The PAM2305 is available in TSOT25, DFN2x2-6 Pin and QFN3x3-16 Pin packages. Features • Efficiency up to 96% • Only 40µA(typ) Quiescent Current • Output Current: Up to 1A • Internal Synchronous Rectifier • 1.5MHz Switching Frequency • Soft Start • Under-Voltage Lockout • Short Circuit Protection • Thermal Shutdown • 5-pin Small TSOT25, DFN2x2-6 Pin and QFN3x3-16 Pin Packages • Pb-Free Package Applications • Cellular Phone • Portable Electronics • Wireless Devices • Cordless Phone • Computer Peripherals • Battery Powered Widgets • Electronic Scales • Digital Frame Pin Assignments Top View TSOT25

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PAM2305 Document number: DSxxxxx Rev. 2 - 6 2 of 17 www.diodes.com January 2013 © Diodes Incorporated PAM2305 A Product Line of Diodes Incorporated Typical Applications Circuit Fixed Output Voltage Adjustable Output Voltage ⎟ ⎠ ⎞ ⎜ ⎝ ⎛ +×= 2R 1R 16.0VO Pin Descriptions Pin Name Package Name Function TSOT25 DFN2x2-6L QFN3x3-16L VIN 1 3 9, 10, 11, 12 Chip main power supply pin. GND 2 5 1, 2, 3, 5 Ground. EN 3 2 7 Enable Control Input. Force this pin voltage above 1.5V, enables the chip, and below 0.3V shuts down the device. VOUT/FB 4 6 4 VOUT: Output voltage feedback pin, an internal resistive divider divides the output voltage down for comparison to the internal reference voltage. FB: Feedback voltage to internal error amplifier, the threshold voltage is 0.6V. SW 5 4 13, 14, 15 The drains of the internal main and synchronous power MOSFET. NC — 1 6, 8, 16 No connection. Functional Block Diagram

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PAM2305 Document number: DSxxxxx Rev. 2 - 6 3 of 17 www.diodes.com January 2013 © Diodes Incorporated PAM2305 A Product Line of Diodes Incorporated Absolute Maximum Ratings (@TA = +25°C, unless otherwise specified.) 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, 5sec °C Recommended Operating Conditions (@TA = +25°C, unless otherwise specified.) Parameter Rating Unit Supply Voltage 2.5 to 5.5 V Operation Temperature Range -40 to +85 °C Junction Temperature Range -40 to +125 Thermal Information Parameter Package Symbol Max Unit Thermal Resistance (Junction to Case) TSOT25 (Note 1) θJC 130 °C/W DFN2x2-6 25 QFN3x3-16 14 Thermal Resistance (Junction to Ambient) TSOT25 θJA 250 DFN2x2-6 68 QFN3x3-16 35 Internal Power Dissipation TSOT25 PD 400 mW DFN2x2-6 980 QFN3x3-16 1470 Note: 1. The maximun output current for TSOT25 package is limited by internal power dissipation capacity as described in Application Information here inafter.

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PAM2305 Document number: DSxxxxx Rev. 2 - 6 4 of 17 www.diodes.com January 2013 © Diodes Incorporated PAM2305 A Product Line of Diodes Incorporated Electrical Characteristics (@TA = +25°C, VIN = 3.6V, VO = 1.8V, CIN = 10µF, COUT = 10µF, L = 4.7µH, unless otherwise specified.) Parameter Symbol Test Conditions Min Typ Max Units Input Voltage Range VIN 2.5 5.5 V Regulated Feedback Voltage VFB 0.588 0.6 0.612 V Reference Voltage Line Regulation ΔVFB 0.3 %/V Regulated Output Voltage Accuracy VO IO = 100mA -3 +3 % Peak Inductor Current IPK VIN = 3V,VFB = 0.5V or VO = 90% 1.5 A Output Voltage Line Regulation LNR VIN = 2.5V to 5V, IO = 10mA 0.2 0.5 %/V Output Voltage Load Regulation LDR IO = 1mA to 800mA 0.5 1.5 % Quiescent Current IQ No load 40 70 µA Shutdown Current ISD VEN = 0V 0.1 1 µA Oscillator Frequency fOSC VO = 100% 1.2 1.5 1.8 MHz VFB = 0V or VO = 0V 500 kHz Drain-Source On-State Resistance RDS(ON) IDS = 100mA P MOSFET 0.3 0.45 Ω N MOSFET 0.35 0.5 Ω SW Leakage Current ILSW ±0.01 1 µA High Efficiency η 96 % EN Threshold High VEH 1.5 V EN Threshold Low VEL 0.3 V EN Leakage Current IEN ±0.01 µA Over Temperature Protection OTP 150 °C OTP Hysteresis OTH 30 °C

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PAM2305 Document number: DSxxxxx Rev. 2 - 6 5 of 17 www.diodes.com January 2013 © Diodes Incorporated PAM2305 A Product Line of Diodes Incorporated Typical Performance Characteristics (@TA = +25°C, CIN = 10µF, CO = 10µF, L = 4.7µH, unless otherwise specified.)

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PAM2305 Document number: DSxxxxx Rev. 2 - 6 6 of 17 www.diodes.com January 2013 © Diodes Incorporated PAM2305 A Product Line of Diodes Incorporated Typical Performance Characteristics (cont.) (@TA = +25°C, CIN = 10µF, CO = 10µF, L = 4.7µH, unless otherwise specified.)

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PAM2305 Document number: DSxxxxx Rev. 2 - 6 7 of 17 www.diodes.com January 2013 © Diodes Incorporated PAM2305 A Product Line of Diodes Incorporated Typical Performance Characteristics (cont.) (@TA = +25°C, CIN = 10µF, CO = 10µF, L = 4.7µH, unless otherwise specified.)

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PAM2305 Document number: DSxxxxx Rev. 2 - 6 8 of 17 www.diodes.com January 2013 © Diodes Incorporated PAM2305 A Product Line of Diodes Incorporated Typical Performance Characteristics (cont.) (@TA = +25°C, CIN = 10µF, CO = 10µF, L = 4.7µH, unless otherwise specified.)

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PAM2305 Document number: DSxxxxx Rev. 2 - 6 9 of 17 www.diodes.com January 2013 © Diodes Incorporated PAM2305 A Product Line of Diodes Incorporated Typical Performance Characteristics (cont.) (@TA = +25°C, CIN = 10µF, CO = 10µF, L = 4.7µH, unless otherwise specified.)