AP3441/L 1MHZ, 3A STEP-DOWN DC-DC BUCK CONVERTER Description Pin Assignments The AP3441 and AP3441L are 3A step-down DC-DC converters. At heavy load, the constant-frequency PWM control performs excellent (Top View) stability and transient response. No external compensation Pin 1 Mark components are required. The AP3441/L supports a range of input voltages from 2.7V to 5.5V FB 1 8 SGND 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 AP3441/L employs 7 2 EN PG 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 1A. Other key features include over-temperature and short circuit VIN 3 6 LX protection, and under-voltage lockout to prevent deep battery discharge. 4 5 PGND NC The AP3441/L delivers 3A maximum output current while consuming only 55A of no-load quiescent current. Ultra-low R integrated DS(ON) MOSFETs and 100% duty cycle operation make the AP3441/L an ideal choice for high output voltage, high current applications which U-DFN2020-8 (Type E) require a low dropout threshold. Pulse skip mode to maintain high efficiency at light-load conditions. The AP3441/L is available in U-DFN2020-8 (Type E) package. Applications Post DC-DC Voltage Regulation Features Set Top Boxes Input Voltage: 2.7V to 5.5V Notebook Computer Output Voltage: 0.6V to V IN PAD 0.6V Reference Voltage with 1.5% Precision 55A (Typical) No Load Quiescent Current Shutdown Current: <1A 100% Duty Cycle Operation 1MHz Switching Frequency No External Compensation Required Short Circuit Protection 441L: Latch Off Protection AP3441: Hiccup Mode Protection Over Voltage Protection AP3441L: Latch Off Protection AP3441: Non Latch Off Protection Thermal Shutdown U-DFN2020-8 (Type E) Package 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) & 2015/863/EU (RoHS 3) compliant. 2. See AP3441/L Typical Applications Circuit L1 2.2mH V =1.8V OUT V =2.7V to 5.5V IN VIN LX R1 C1 C C IN OUT 22pF 200k 22 mF 22 m F x2 OFF ON FB EN R2 100k PG PGND SGND Pin Descriptions Pin Number Pin Name Function 1 FB Feedback voltage to internal error amplifier, the threshold voltage is 0.6V. Power good indicator, open drain output. PG is pulled up to VIN when the output voltage is 2 PG within 20% of the regulation level, otherwise it is low. 3 VIN Bias supply. Chip main power supply pin 4 PGND Power ground pin 5 NC No connection 6 LX The drains of the internal main and synchronous power MOSFET. Enable control input. Force this pin voltage above 1.5V enables the chip, and below 0.4V 7 EN shuts down the device. 8 SGND Signal ground pin Exposed metal pad on the underside of the package without any electrical connection to EP Exposed Pad internal circuit. It is recommended to connect this pad to the PC board ground plane in order to improve heat dissipation. 2 of 13 AP3441/L September 2019 Diodes Incorporated www.diodes.com Document number: DS39754 Rev. 3 - 2 AP3441/L