Is Now Part of
To learn more about ON Semiconductor, please visit our website at
www.onsemi.com
Please note: As part of the Fairchild Semiconductor integration, some of the Fairchild orderable part numbers
will need to change in order to meet ON Semiconductor’s system requirements. Since the ON Semiconductor
product management systems do not have the ability to manage part nomenclature that utilizes an underscore
(_), the underscore (_) in the Fairchild part numbers will be changed to a dash (-). This document may contain
device numbers with an underscore (_). Please check the ON Semiconductor website to verify the updated
device numbers. The most current and up-to-date ordering information can be found at www.onsemi.com. Please
email any questions regarding the system integration to Fairchild_questions@onsemi.com.
ON Semiconductor and the ON Semiconductor logo are trademarks of Semiconductor Components Industries, LLC dba ON Semiconductor or its subsidiaries in the United States and/or other countries. ON Semiconductor owns the rights to a number
of patents, trademarks, copyrights, trade secrets, and other intellectual property. A listing of ON Semiconductor’s product/patent coverage may be accessed at www.onsemi.com/site/pdf/Patent-Marking.pdf. ON Semiconductor reserves the right
to make changes without further notice to any products herein. ON Semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does ON Semiconductor assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages. Buyer is responsible for its products and applications using ON
Semiconductor products, including compliance with all laws, regulations and safety requirements or standards, regardless of any support or applications information provided by ON Semiconductor. “Typical” parameters which may be provided in ON
Semiconductor data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All operating parameters, including “Typicals” must be validated for each customer application by customer’s
technical experts. ON Semiconductor does not convey any license under its patent rights nor the rights of others. ON Semiconductor products are not designed, intended, or authorized for use as a critical component in life support systems or any FDA
Class 3 medical devices or medical devices with a same or similar classification in a foreign jurisdiction or any devices intended for implantation in the human body. Should Buyer purchase or use ON Semiconductor products for any such unintended
or unauthorized application, Buyer shall indemnify and hold ON Semiconductor and its officers, employees, subsidiaries, affiliates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out
of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that ON Semiconductor was negligent regarding the design or manufacture of the part. ON Semiconductor
is an Equal Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
FAN2306AMPX / FAN2306MAMPX
6 A Synchronous Buck Regulator
Features
Description
The FAN2306A / FAN2306MA are highly efficient
synchronous buck regulators. They are capable of
operating with an input range from 4.5 V to 18 V,
supporting 6 A continuous load currents.
VIN Range: 4.5 V to 18 V
High Efficiency: Over 96% Peak
Continuous Output Current: 6 A
PFM Mode for Light-Load Efficiency
Ultrasonic or No-Ultrasonic Mode Options
Excellent Line and Load Transient Response
Precision Reference: ±1% Over Temperature
Output Voltage Range: 0.6 to 5.5 V
Programmable Frequency: 200 kHz to 1.5 MHz
Programmable Soft-Start
Low Shutdown Current
Adjustable Sourcing Current Limit
Internal Boot Diode
Thermal Shutdown
Halogen and Lead Free, RoHS Compliant
Applications
These devices utilize Fairchild’s constant on-time
control architecture to provide excellent transient
response and to maintain a relatively constant switching
frequency. The FAN2306A / FAN2306MA utilize Pulse
Frequency Modulation (PFM) mode to maximize lightload efficiency by reducing switching frequency when
the inductor is operating in Discontinuous Conduction
Mode (DCM) at light loads. The FAN2306A includes an
ultrasonic mode with minimum frequency clamp to keep
the switching frequency above the audible range, while
the FAN2306MA does not include the minimum
frequency clamp to maximize efficiency to extremely
light loads.
Switching frequency and over-current protection can
be programmed to provide a flexible solution for
various applications. Output over-voltage, undervoltage, over-current, and thermal shutdown protections
help prevent damage to the device during fault
conditions. After thermal shutdown is activated, a
hysteresis feature restarts the device when normal
operating temperature is reached.
Servers and Desktop Computers
NVDC Notebooks, Netbooks
Game Consoles
Telecommunications
Storage
Base Stations
Ordering Information
Part Number
Configuration
Operating
Temperature
Range
Output
Current (A)
FAN2306AMPX
PFM with Ultrasonic Mode
-40 to 125°C
6
FAN2306MAMPX
PFM, No Ultrasonic Mode
-40 to 125°C
6
© 2015 Fairchild Semiconductor Corporation
FAN2306A / FAN2306MA • Rev. 1.0
Package
34-Lead, PQFN,
5.5 mm x 5.0 mm
www.fairchildsemi.com
FAN2306AMPX / FAN2306MAMPX — 6 A Synchronous Buck Regulator
September 2015
FAN2306AMPX / FAN2306MAMPX — 6 A Synchronous Buck Regulator
Typical Application Diagram
VBIAS = 5V
R11
10Ω
C9
0.1µF
C10
2.2µF
PVCC
VCC
Ext
EN
VIN = 12V
CIN
0.1µF
VIN
CIN
2x10µF
PVIN
C3
0.1µF
EN
VOUT = 1.2V
IOUT=0-6A
BOOT
FAN2306A
FAN2306MA
PGOOD
L1
1.2µH
SW
ILIM
SOFT START
R5 1.5kΩ
C7
15nF
R2
1.5kΩ
C4
0.1µF
R3
10kΩ
C5
100pF
FREQ
COUT
4x47µF
FB
R9
54.9kΩ
AGND
R6
4.99kΩ
PGND
R4
10kΩ
Figure 1. Typical Application
Functional Block Diagram
VIN
BOOT
PVIN
PVCC
PVCC
VCC
VCC
VCC UVLO
0.8V/
2.0V
PVCC
EN
ENABLE
VCC
VCC
10µA
Modulator
HS Gate
Driver
SS
FB
FB
Comparator
VREF
SW
FREQ
Control
Logic
x1.2
2nd Level Over
Voltage Comparator
x1.1
1st Level Over
Voltage Comparator
x0.9
Under Voltage
Comparator
PFM
Comparator
PVCC
LS Gate
Driver
VCC
PGOOD
Thermal
Shutdown
10µA
Current Limit
Comparator
AGND
ILIM
PGND
Figure 2. Block Diagram
© 2015 Fairchild Semiconductor Corporation
FAN2306A / FAN2306MA • Rev. 1.0
www.fairchildsemi.com
2
9
VIN
PVIN
9
SW
PVIN
8
BOOT
PVIN
7
AGND
PVIN
6
PVIN
PVIN
5
PVIN
AGND
4
PVIN
BOOT
3
PVIN
SW
2
PVIN
VIN
1
8
7
6
5
4
3
2
1
10
PVIN
PVIN 10
34
NC
11
PVIN
PVIN 11
33
NC
12
SW
SW
12
32
FREQ
13
SW
SW 13
31
SS
14
SW
SW
30 PGOOD
29
15
SW
SW 15
29
EN
NC
28
16
SW
SW 16
28
NC
FB
27
17
SW
SW 17
27
FB
25
24
23
22
21
20
ILIM
AGND
SW
PGND
PGND
19
14
18
Figure 3. Pin Assignments, Bottom View
18
19
20
21
22
23
24
25
26
VCC
26
PVCC
EN
VCC
PGOOD 30
PVCC
SW
(P3)
ILIM
AGND
(P1)
AGND
31
SW
SS
PGND
32
PGND
FREQ
PGND
33
PGND
NC
PVIN
(P2)
PGND
34
PGND
NC
Figure 4. Pin Assignments, Top View
Pin Definitions
Name
Pad / Pin
PVIN
P2, 5-11
Description
Power input for the power stage
VIN
1
Input to the modulator for input voltage feed-forward
PVCC
25
Power input for the low-side gate driver and boot diode
VCC
26
Power supply input for the controller
PGND
18-21
AGND
SW
P1, 4, 23
Power ground for the low-side power MOSFET and for the low-side gate driver
Analog ground for the analog portions of the IC and for substrate
P3, 2, 12-17, 22 Switching node; junction between high-and low-side MOSFETs
BOOT
3
Supply for high-side MOSFET gate driver. A capacitor from BOOT to SW supplies the
charge to turn on the N-channel high-side MOSFET. During the freewheeling interval
(low-side MOSFET on), the high-side capacitor is recharged by an internal diode
connected to PVCC.
ILIM
24
Current limit. A resistor between ILIM and SW sets the current limit threshold.
FB
27
Output voltage feedback to the modulator
EN
29
Enable input to the IC. Pin must be driven logic HIGH to enable, or logic LOW to
disable.
SS
31
Soft-start input to the modulator
FREQ
32
On-time and frequency programming pin. Connect a resistor between FREQ and
AGND to program on-time and switching frequency.
PGOOD
30
Power good; open-drain output indicating VOUT is within set limits.
NC
28, 33-34
Leave pin open or connect to AGND.
© 2015 Fairchild Semiconductor Corporation
FAN2306A / FAN2306MA • Rev. 1.0
www.fairchildsemi.com
3
FAN2306AMPX / FAN2306MAMPX — 6 A Synchronous Buck Regulator
Pin Configuration
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be
operable above the recommended operating conditions and stressing the parts to these levels is not recommended.
In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability.
The absolute maximum ratings are stress ratings only.
Symbol
VPVIN
VIN
VBOOT
VSW
Parameter
Conditions
Min. Max. Unit
Power Input
Referenced to PGND
-0.3
25.0
V
Modulator Input
Referenced to AGND
-0.3
25.0
V
Referenced to PVCC
-0.3
26.0
V
Referenced to PVCC,