AP3591 Datasheet, PDF (1/18 Pages) Diodes Incorporated – SINGLE PHASE SYNCHRONOUS BUCK CONTROLLER

Description
A Product Line of
Diodes Incorporated
AP3591
SINGLE PHASE SYNCHRONOUS BUCK CONTROLLER
Pin Assignments
The AP3591 is a synchronous adaptive on-time buck controller
providing high efficiency, excellent transient response and high DC
output accuracy for low voltage regulation in notebook application.
The constant-on-time PWM control scheme handles wide input/output
voltage ratios with ease and features small external component count
and fast transient response.
The operation mode is selectable by EN voltage. A Diode Emulation
Mode (DEM) is activated for increasing efficiency at light loads, while
PWM mode is activated only for low noise operation. The AP3591
also integrates internal Soft-start, UVLO, OVP, OTP, and
programmable OCP to protect the circuit. A Power Good signal is
employed to monitor the output voltage.
The AP3591 is available in U-QFN3535-14 package.
(Top View)
Pin 1 Mark
TON 2
VOUT 3
VDD 4
FB 5
PGOOD 6
1
14
13 UGATE
12 PHASE
EP
11 CS
10 VDDP
9 LGATE
7
8
U-QFN3535-14
Features
Applications
 Fixed Frequency Constant On-time Control; Resistor
Programmable Frequency Adjustable from 100kHz to 700kHz
 Good Stability Independent of the Output Capacitor ESR
 Quick Load Step Response
 Input Voltage Range: 4.5V to 26V
 Output Voltage Range: 0.75V to 5.5V
 CCM/DEM Mode Selection
 Integrated Bootstrap Diode
 Resistor Programmable Current Limit by Low-side RDS_ON
Sense
 Integrated Negative Over Current Limit
 Integrated OVP/UVP and Over Thermal Shutdown Function
 Power Good Indicator
 Internal Soft-start
 Integrate Output Discharge (Soft-stop)
 Safe Start-up into Pre-biased Loads
 Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2)
 Halogen and Antimony Free. “Green” Device (Note 3)
 Notebook Computer, AIO PC
 Low-voltage Distribute Power
 I/O Supplies
Notes:
1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant.
2. See http://www.diodes.com/quality/lead_free.html for more information about Diodes Incorporated’s definitions of Halogen- and Antimony-free, "Green"
and Lead-free.
3. Halogen- and Antimony-free "Green” products are defined as those which contain <900ppm bromine, <900ppm chlorine (<1500ppm total Br + Cl) and
<1000ppm antimony compounds.
AP3591
Document number: DS36906 Rev. 1 - 2
1 of 18
www.diodes.com
March 2014
© Diodes Incorporated