Diodes AUR9707 User Manual
Dual High-efficiency PWM Step-down DC-DC Converter with OVP AUR9707
Data Sheet
General Description
The AUR9707 is a high efficiency step-down
DC-DC voltage converter. The chip operation is
optimized using constant frequency, peak-current
mode architecture with built-in synchronous power
MOSFET switchers and internal compensators to
reduce external part counts. It is automatically
switching between the normal PWM mode and LDO
mode to offer improved system power efficiency
covering a wide range of loading conditions.
The oscillator and timing capacitors are all built-in
providing an internal switching frequency of 1.5MHz
that allows the use of small surface mount inductors
and capacitors for portable product implementations.
Additional features included Soft Start (SS), Under
Voltage Lock Out (UVLO), Input Over Voltage
Protection (IOVP) and Thermal Shutdown Detection
(TSD) are integrated to provide reliable product
applications.
The device is available in adjustable output voltage
versions ranging from 1V to 3.3V, and is able to
deliver up to 1A.
The AUR9707 is available in WDFN-3×3-12
package.
Features
• Dual Channel High Efficiency Buck Power
Converter
• Low Quiescent Current
• Output Current: 1A
• Adjustable Output Voltage from 1V to 3.3V
• Wide Operating Voltage Range: 2.5V to 5.5V
•
Built-in Power Switches for Synchronous
Rectification with High Efficiency
• Feedback Voltage: 600mV
• 1.5MHz Constant Frequency Operation
• Automatic PWM/LDO Mode Switching Control
• Thermal Shutdown Protection
• Low Drop-out Operation at 100% Duty Cycle
• No Schottky Diode Required
• Internal Input Over Voltage Protection
Applications
• Mobile Phone, Digital Camera and MP3 Player
• Headset, Radio and Other Hand-held Instrument
• Post DC-DC Voltage Regulation
• PDA and Notebook Computer
WDFN-3×3-12
Figure 1. Package Type of AUR9707
Feb. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited
1
Data Sheet
Dual High-efficiency PWM Step-down DC-DC Converter with OVP AUR9707
Pin Configuration
D Package
(WDFN-3×3-12)
Pin 1 Dot
by Marking
1
2
3
Exposed
4
5
6
Pad
12
11
10
9
8
7
Figure 2. Pin Configuration of AUR9707 (Top View)
Pin Description
Pin Number Pin Name Function
1 VIN2 Power supply input of channel 2
2 LX2 Connection from power MOSFET of channel 2 to inductor
3, 9 GND
4 FB1 Feedback voltage of channel 1
5, 11 NC1,NC2 No internal connection (floating or connecting to GND)
6 EN1 Enable signal input of channel 1, active high
7 VIN1 Power supply input of channel 1
8 LX1 Connection from power MOSFET of channel 1 to inductor
10 FB2 Feedback voltage of channel 2
12 EN2 Enable signal input of channel 2, active high
This pin is the GND reference for the NMOSFET power stage. It
must be connected to the system ground
Feb. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited
2
Data Sheet
Dual High-efficiency PWM Step-down DC-DC Converter with OVP AUR9707
Functional Block Diagram
FB1, FB2
EN 1, EN2
6, 12
Generator
4, 1 0
Bandgap
Reference
Over Current
Comparator
Bias
Saw-tooth
Generator
Oscillator
+
Soft
Start
-
+
Error
Amplifier
-
+
Figure 3. Functional Block Diagram of AUR9707
+
-
Modulator
Over Voltage
Comparator
Control
Logic
Reverse Inductor
Current Comparator
Thermal
Shutdown
Current
Sensing
Buffer &
Dead Time
Control
Logic
VIN 1, VIN 2
-
+
7, 1
3, 9
GND
8, 2
LX1, LX 2
Ordering Information
AUR9707 A
Circuit Type
A: Adjustable Output
5
Package
WDFN-3×3-12 -40 to 80°C AUR9707AGD 9707A Tape & Reel
Temperature
Range
Part Number Marking ID Packing Type
BCD Semiconductor's Pb-free products, as designated with "G" in the part number, are RoHS compliant and
green.
Feb. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited
3
Package
D: WDFN-3×3-12
G: Green
Data Sheet
Dual High-efficiency PWM Step-down DC-DC Converter with OVP AUR9707
Absolute Maximum Ratings (Note 1)
Parameter Symbol Value Unit
Supply Input Voltage VIN
Enable Input Voltage VEN
Output Voltage V
V
IN1-VIN2
Power Dissipation (On PCB, TA=30°C) PD
Thermal Resistance (Junction to Ambient, Simulation) θJA
Thermal Resistance (Junction to Case, Simulation) θJC
Operating Junction Temperature TJ
Operating Temperature TO
Storage Temperature TS
ESD (Human Body Model) V
ESD (Machine Model) VMM
Note 1: Stresses greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to
the device. These are stress ratings only, and functional operation of the device at these or any other conditions
beyond those indicated under “Recommended Operating Conditions” is not implied. Exposure to “Absolute
Maximum Ratings” for extended periods may affect device reliability.
Note 2:│V
Voltage (Note 2) VDF
IN1-VIN2
│voltage difference can not exceed 0.3V, otherwise, the chip will be damaged.
OUT
HBM
0 to 6.5
-0.3 to VIN+0.3
-0.3 to VIN+0.3
-0.3 to 0.3
2.31
41
4.2
160
-40 to 85
-55 to 150
2000
200
V
V
V
V
W
°C/W
°C/W
°C
°C
°C
V
V
Recommended Operating Conditions
Parameter Symbol Min Max Unit
Supply Input Voltage VIN 2.5 5.5 V
Junction Temperature Range TJ -20 125 °C
Ambient Temperature Range TA -40 80 °C
Feb. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited
4
Data Sheet
Dual High-efficiency PWM Step-down DC-DC Converter with OVP AUR9707
Electrical Characteristics
VIN=3.6V, V
Parameter Symbol Conditions Min Typ Max Unit
Input Voltage Range VIN 2.5 5.5 V
=2.5V, V
OUT
=0.6V, L=2.2µH, CIN=4.7µF, C
REF
=10µF, TA=25°C, I
OUT
MAX
=1A.
Shutdown Current I
Regulated1Feedback
Voltage
Regulated Output
Voltage Accuracy
∆V
Peak Inductor
Current
Oscillator Frequency f
PMOSFET RON R
NMOSFET RON R
Input DC Bias
Current
LX Leakage Current ILX
V
OFF
For Adjustable Output Voltage 0.585 0.6 0.615 V
V
FB
OUT/VOUT
I
OSC
ON(P)
ON(N)
I
V
PK
V
VIN=3.6V, I
VIN=2.5V, I
S
=0 0.1 1 µA
EN
=2.5V to 5.5V;
V
IN
=0 to 1A
I
OUT
=3V, VFB=0.5V 1.5 A
IN
=3.6V 1.2 1.5 1.8 MHz
IN
=200mA 0.28 Ω
OUT
=200mA 0.38 Ω
OUT
VIN=3.6V, I
=2.5V, I
V
IN
=5V, VEN=0V, VLX=0V or
V
IN
=200mA 0.25
OUT
=200mA
OUT
5V
-3 3 %
0.35
0.01 0.1 µA
µA
Feedback Current IFB 30 nA
Input Over Voltage
Protection
6 V
V
LOVP
EN Leakage Current IEN 0.01 0.1 µA
EN High-level Input
Voltage
EN Low-Level Input
Voltage
Under Voltage Lock
Out
VIN=2.5V to 5.5V 1.5 V
V
EN_H
V
V
EN_L
=2.5V to 5.5V 0.6 V
IN
1.8 V
Hysteresis 0.1 V
Thermal Shutdown TSD 150 °C
Feb. 2012 Rev. 1. 1 BCD Semiconductor Manufacturing Limited
5
Loading...