Global Mixed-mode Technology Inc.
AT1529
1MHz, All-Ceramic, 3.2A PWM Buck DC/DC Converter
Features
Ceramic Input and Output Capacitors Efficiency Up to 94% Operate from 2.5V to 6V supply Adjustable Output from 0.8V to VIN Internal Soft-Start Short-Circuit and Thermal-Overload Protection Input Over Voltage Protection RoHS Compliant
Applications
ASIC/DSP/µP/FPGA Core and I/O Voltages Set-Top Boxes Cellular Base Stations Networking and Telecommunications
General Description
The AT1529 high-efficiency, DC/DC buck converter delivers up to 3.2A of output current. The device operates from an input voltage of 2.5V to 6V and provides an output voltage from 0.8V to VIN, making the AT1529 ideal for on-board post-regulation applications.
The AT1529 operate at a fixed frequency of 1MHz with an efficiency of up to 94%. The high operating frequency minimizes the size of external components. Internal soft-start control circuitry reduces inrush current. Short-circuit and thermal-overload protections improve design reliability.
The AT1529 are available in a space-saving SOP-8 and TDFN3X3-8 package.
Ordering Information
ORDER NUMBER
MARKING
AT1529F11U
A1529
AT1529RD1U
A1529
Note: F1:SOP-8 (FD) RD: TDFN3X3-8
1: Bonding Code
U: Tape & Reel
TEMP.
RANGE -40°C to +85°C -40°C to +85°C
PACKAGE (Green)
SOP-8 (FD) TDFN3X3-8
Pin Configuration
Typical Application Circuit
VCC 1 REF 2 GND 3
FB 4
AT1529
Thermal Pad
8 VIN 7 LX 6 PGND 5 EN
VCC 1
REF GND
FB
2 3 4
AT1529
Thermal Pad
8 VIN 7 LX 6 PGND 5 EN
SOP-8 (FD)
TDFN3X3-8
Note: Recommend connecting the Thermal Pad to the Ground for excellent power dissipation.
VIN 5V
10µF
AT1529
8 VIN
LX 7
10Ω
0.1µF
1 VCC 5 EN
ON OFF PGND
6
4 FB
REF 2
GND 0.1µF 3
VOUT = 0.8V ×
(1+
R1 R2
)
2.2µH
CFB* (option)
R1 R2 50k 16k
VOUT 3.3V 22µF
Ver: 0.3 Nov 29, 2010
TEL: 886-3-5788833 http://www.gmt.com.tw
1
Global Mixed-mode Technology Inc.
AT1529
Absolute Maximum Ratings
VIN, VCC, REF to GND . . . . . . . . . . . . . . . -0.3V to +7V
LX to PGND . . . . . . . . . . . . . . . . . . . .-1V to (VIN+1V)
EN, FB to GND. . . . . . . . . . . . . . -0.3V to (VCC + 0.3V)
VIN to VCC . . . . . . . . . . . . . . . . . . . . . . -0.3V to +0.3V
PGND to GND . . . . . . . . . . . . . . . . . . . .-0.3V to +0.3V Thermal Resistance Junction to Ambient, (θJA) * SOP-8 (FD) . . . . . . . . . . . . . . . . . . . . . . . . . .108°C/W TDFN3X3-8 . . . . . . . . . . . . . . . . . . . . . . . . . . .98°C/W Continuous Power Dissipation (TA = +25°C) * SOP-8 (FD). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2W
TDFN3X3-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.4W
Thermal Resistance Junction to Case, (θJC) SOP-8 (FD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12°C/W TDFN3X3-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . .30°C/W Operating Temperature Range . . . . . . . .-40°C to 85°C Maximum Junction Temperature. . . . . . . . . . . . .150°C Storage Temperature Range. . . . . . . . .-65°C to 165°C Reflow Temperature (soldeing,10 sec) . . . . . . . .260°C
* Please refer to 1in2 of 1oz PCB Layout Section. Stress beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device.
Electrical Characteristics
(VIN= VCC= 3.3V, PGND = GND, FB in regulation, CREF= 10nF, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETER IN Voltage Range
Supply Current
VCC Undervoltage Lockout Threshold REF Voltage
EN Enable Threshold
Output Voltage Range
Output Voltage Line Regulation Output Voltage Load Regulation FB Regulation Voltage (Error Amp Only) FB Input Bias Current LX On-Resistance, PMOS LX On-Resistance, NMOS
LX Current-Limit Threshold
LX Leakage Current
LX Switching Frequency LX Maximum Duty Cycle LX Minimum Duty Cycle
Thermal-Shutdown Threshold
Maximum Duty Cycle Minimum On Time
CONDITION
No switching (EN=VCC) Shutdown (EN=0V)
VIN = 5V
When LX starts/stops switching
IREF = 0, VIN = 2.5V to 5V Logic High
Logic Low
When using external feedback resistors to
drive FB
VIN = 3V to 5V 0A