AP3429/A 1.0MHZ, 2A STEP-DOWN DC-DC BUCK CONVERTER Description Pin Assignments The AP3429/A is a 2A step-down DC-DC converter. At heavy load, the constant frequency PWM control performs excellent stability and (Top View) transient response. No external compensation components are required. FB EN 1 5 The AP3429/A supports a range of input voltages from 2.7V to 5.5V, GND 2 allowing the use of a single Li+/Li- polymer cell, multiple Alkaline/NiMH cell, and other standard power sources. The output voltage is adjustable from 0.6V to the input voltage. The AP3429/A LX 3 4 VIN employs 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 TSOT25 than 1A. Other key features include over-temperature and short circuit protection, and under-voltage lockout to prevent deep battery Features discharge. Output Current: Up to 2A The AP3429/A delivers 2A maximum output current while consuming Output Voltage: 0.6V to V IN only 90A of no-load quiescent current. Ultra-low R integrated DS(ON) Input Voltage: 2.7V to 5.5V MOSFETs and 100% duty cycle operation make the AP3429/A an Shutdown Current: <1A ideal choice for high output voltage, high current applications which 100% Duty Cycle Operation require a low dropout threshold. 1MHz Switching Frequency Internal Soft Start The AP3429/A is available in TSOT25 package. No External Compensation Required Short Circuit Protection Applications AP3429: Latch Off Protection AP3429A: Hiccup Mode Protection 5V or 3.3V Point of Load Conversion Over Voltage Protection Telecom/Networking Equipment AP3429: Latch Off Protection Set Top Boxes AP3429A: No Latch Off Protection Storage Equipment Thermal Shutdown Video Cards TSOT25 package DDR Power Supply Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. Green Device (Note 3) Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. 2. See AP3429/A AP3429/A Typical Applications Circuit V =2.7V to 5.5V IN 4 VIN C IN L1 2.2 mH 22 mF V =1.8V 3 OUT LX 2 R1 C1 C OUT GND 22pF 300k 22 m F x2 5 1 FB EN ON OFF R2 150k Pin Descriptions Pin Number Pin Name Function Enable control input. Force this pin voltage above 1.5V enables the chip, and below 0.4V shuts 1 EN down the device. 2 GND Ground pin. 3 LX The drains of the internal main and synchronous power MOSFETs. 4 VIN Bias supply. Chip main power supply pin. 5 FB Feedback voltage to internal error amplifier. The threshold voltage is 0.6V. 2 of 11 AP3429/A August 2015 Diodes Incorporated www.diodes.com Document number: DS36561 Rev. 3 - 2 NEW PRODUCT