AME AME5107

AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n General Description
n Applications
l PC Motherboard
AME5107provides low-ripple power, high efficiency, and
excellent transient characteristics. The PWM control circuit is able to vary the duty ratio linearly from 0 up to
100%. This converter also contains an error amplifier circuit as well as a soft-start circuit that prevents overshoot
at startup. An enable function, an over current protect function and a short circuit protect function are built inside,
and when OCP or SCP happens, the operation frequency
will be reduced from 350KHz to 30KHz. Also, an internal
compensation block is built in to minimum external component count.
l LCD Monitor
l Graphic Card
l DVD-Video Player
l Telecom Equipment
l ADSL Modem
l Printer and other Peripheral Equipment
l Microprocessor core supply
l Networking power supply
With the addition of an internal P-channel Power MOS,
a coil, capacitors, and a diode connected externally, these
ICs can function as step-down switching regulators. They
serve as ideal power supply units for portable devices when
coupled with the SOP-8L mini-package, providing such
outstanding features as low current consumption. Since
this converter can accommodate an input voltage up to
18V, it is also suitable for the operation via an AC adapter.
n Features
l Input voltage: 3.6V to 18V.
l Output voltage: 0.8V to VCC.
l Duty ratio: 0% to 100% PWM control
C
l Oscillation frequency: 350KHz typ.
l Soft-start, Current limit, Enable function
l Thermal Shutdown function
l Built-in internal SW P-channel MOS
l SOP-8 Package
l All AME’ s Lead Free Products Meet RoHS
Standards
Rev.A.01
S
1
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Typical Application
Note: VOUT = V FB x (1+RA/RB)
RB=0.7K~ 5K Ω
VIN =12V,IMAX=3A
VOUT
2.5V
3.3V
5V
L1 Value
22uH
27uH
33uH
n Function Block Diagram
SW
Oscillation
Circuit
Reference Voltage
Source with Soft Start
IN
PWM-Switched
Control Circuit
+
-
FB
Thermal
Shutdown
VEN
100µA
GND
EN
2
OCSET
Rev.A.01
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Pin Configuration
SOP-8
Top View
8
7
6
AME5107
5
1. FB
2. EN
3. OCSET
AME5107
4. IN
5. SW
6. SW
1
2
3
4
7. GND
8. GND
* Die Attach:
Conductive Epoxy
n Pin Description
Pin Number
Pin Name
Pin Description
Output voltage Feedback input.
Set the outputCvoltage by selecting values for Ra and Rb using:
1
FB
 Ra + Rb 
V OUT = 0 .8V 

 Rb 
Connect the ground of the feedback network to an AGND (Analog
Ground) plane which should be tied directly to the GND pin.
Rev.A.01
Enable Control Input, active high.
The enable pin is an active high control. Tie this pin above 2V to enable
the device. Tie this pin below 0.8V to shut down the device. In shutdown,
all function are disabled. Do not leave EN pin floating.
2
EN
3
OCSET
4
IN
5,6
SW
Switch Node Connection to Inductor.
7,8
GND
Ground.
Tie directly to ground plane.
Add an external resistor to set max output current.
Input Supply Voltage Pin.
Bypass this pin with a capacitor. The capacitor shall be placed as close
to the device as possible.
3
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Ordering Information
AME5107 x x x x xxx x
Special Feature
Output Voltage
Number of Pins
Package Type
Operating Ambient Temperature Range
Pin Configuration
Pin
Configuration
A
(SOP-8)
Operating Ambient
Package Type
Temperature Range
1. FB
2. EN
3. OCSET
4. IN
5. SW
6. SW
7. GND
8. GND
I:
-20OC to 85OC
H: SOP
Number
of
Pins
Output Voltage
Special Feature
A: 8
ADJ: Adjustable
Z:
Lead free
n Ordering Information
Part Number
Marking*
Output Voltage
Package
Operating Ambient
Temperature Range
AME5107AIHAADJZ
5107
AADJ
yyww
ADJ
SOP-8
-20OC to 85OC
Note: ww represents the date code.
* A line on top of the first letter represents lead free plating such as 5107 AADJ yyww.
Please consult AME sales office or authorized Rep./Distributor for the availability of package type.
4
Rev.A.01
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Absolute Maximum Ratings
Parameter
Symbol
Maximum
Input Supply Voltage
IN
-0.3V to 22V
EN,SW Pin Voltages
VEN , VSW
-0.3V to 0.3V
VFB
-0.3V to VIN
FB Pin Voltage
Unit
V
TBD*
ESD Classification
Caution: Stree above the listed absolute maximum rating may cause permanent damage to the device.
*HBM B: 2000~3999V
n Recommended Operating Conditions
Parameter
Symbol
Rating
Unit
Ambient Temperature Range
TA
-20 to 85
o
C
Junction Temperature Range
TJ
-20 to 125
o
C
Storage Temperature Range
TSTG
-40 to 150
o
C
C
n Thermal Information
Parameter
Package
Thermal Resistance*
(Junction to Case)
SOP-8
Die Attach
Symbol
Maximum
θJC
60
Unit
o
Thermal Resistance
(Junction to Ambient)
SOP-8
Internal Power Dissipation
SOP-8
Conductive Epoxy
Solder Iron (10 Sec)**
θJA
150
PD
810
350
C/W
mW
o
C
* Measure θJC on center of molding compound if IC has no tab.
** MIL-STD-202G-210F
Rev.A.01
5
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Electrical Specifications
VIN = 12V, TA = 25oC,Unless otherwise specified.
Parameter
Test Condition
Input Voltage
VIN
Feedback Voltage
VFB
IOUT=0.1A
FB Pin Bias Current
IFB
IOUT=0.1A
Switch Current
ISW
Current Consumption During
Power Off
ISSS
Min
Typ
3.6
0.782
Max Units
18
V
0.8
0.818
V
0.1
0.5
µA
3.5
A
VEN =0V
10
µA
Output Voltage Line Regulation
REGLINE
VIN =5V to 18V
2
4
%
Output Voltage Load Regulation
REGLOAD
IOUT=0.1A to 3A
0.2
0.5
%
350
400
KHz
Oscillator Frequency
fOSC
Frequency of Current Limit or
Short Circuit Protect
fOSC1
Enable High (enabled)
VIH_EN
Measure wave form at SW
pin
Measure wave form at SW
pin
Evaluate oscillation at SW
pin
Evaluate oscillation stop at
SW pin
300
10
KHz
2.0
V
Enable Low (shutdown)
VIL_EN
EN High Input Current
IIH_EN
20
µA
EN Low Input Current
IIL_EN
-10
µA
OCSET Pin Bias Current
IOCSET
75
90
105
µA
t SS
0.3
2
5
mS
VIN =5V
110
150
VIN =12V
70
100
Soft Start Time
Internal MOSFET RDSON
6
Symbol
RDSON
VFB=0V
0.8
mΩ
Rev.A.01
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Detailed Description
PWM Control
The AME5107 consists of DC/DC converters that employ a pulse-width modulation (PWM) system. In converters of
the AME5107, the pulse width varies in a range from 0 to 100%, according to the load current. The ripple voltage
produced by the switching can easily be removed through a filter because the switching frequency remains constant.
Therefore, these converters provide a low-ripple power over broad ranges of input voltage and load current.
Under Voltage Lockout
The under voltage lockout circuit of the AME5107 assures that the high-side MOSFET driver outputs remain in the off
state whenever the supply voltage drops below 3.3V. Normal operation resumes once VCC rises above 3.5V.
RDS(ON) Current Limiting
The current limit threshold is setting by the external resistor connecting from VCC supply to OCSET. The internal
100uA sink current crossing the resistor sets the voltage at the pin of OCSET. When the PWM voltage is less than the
voltage at OCSET, an over-current condition is triggered.
ILOAD x RDS(ON) =IOCSET x ROCSET
See above formula for setting the current limit value.
C
Rev.A.01
7
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Characterization Curve(For reference only)
Vin vs. FB
Line Regulation
0.84
3.40
0.83
3.35
0.82
0.81
V OUT(V)
VFB(V)
3.30
0.80
0.79
0.78
3.25
3.20
0.77
VIN =12V
0.76
VOUT=3.3V
0.75
V OUT =3.3V
3.15
I OUT =0.2A
0.74
0
2
4
6
8
10
12
14
16
IOUT =0.2A
3.10
18
0
2
4
6
8
10
12
VIN(V)
VI N (V)
Load Regulation
VIN v.s Frequency
5.1
14
16
18
380
5.0
375
4.9
370
Fosc (KHZ)
VOUT ( V )
4.8
4.7
4.6
4.5
365
360
355
4.4
350
4.3
4.1
0
340
0.5
1
1.5
2
2.5
V OUT=3.3V
345
VIN =12V
4.2
3
IOUT =0.2A
0
2
4
6
8
10
IOUT ( A )
V IN (V)
Efficiency
Vout Ripple
12
14
16
18
100
90
Efficiency (% )
80
VOUT=5V
70
VOUT =3.3V
V SW
5V /div
VOUT
20 mV/div
60
50
40
30
VIN = 12V
V OUT= 3.3V
I OUT=0.1A
20
10
0
8
0.5
1
1.5
IOUT ( A )
2
2.5
3
Rev.A.01
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Characterization Curve(For reference only)
Vout Ripple
Frequency of short current protect
VSW
5V/div
VSW
VOUT
5V/div
20mV/div
VIN =12V
VOUT=3.3V
I OUT=3A
Soft start time
VOUT
VIN =12V
2 V/div
VO U T=5V
ILOAD=3A
V SW
5 V/div
EN
5 V/div
C
Rev.A.01
9
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Tape and Reel Dimension
SOP-8
P
PIN 1
W
AME
AME
Carrier Tape, Number of Components Per Reel and Reel Size
10
Package
Carrier Width (W)
Pitch (P)
Part Per Full Reel
Reel Size
SOP-8
12.0±0.1 mm
4.0±0.1 mm
2500pcs
330±1 mm
Rev.A.01
AME, Inc.
PWM Control 3A Buck
Converter
AME5107
n Package Dimension
SOP-8
Side View
Top View
C
SYMBOLS
MAX
MIN
MAX
A
1.35
1.75
0.05315
0.0689
A1
0.10
0.30
0.00394 0.01181
A2
L
D
θ
INCHES
MIN
E
H
MILLIMETERS
1.473 REF
0.05799 REF
B
0.33
0.51
0.01299 0.02008
0.19
0.25
0.00748 0.00984
D
4.80
5.33
0.18898 0.20984
7o(4X)
E
3.80
4.00
0.14961 0.15748
e
1.27 BSC
A
e
A1
A2
C
Front View
B
0.05000 BSC
L
0.40
1.27
0.01575 0.05000
H
5.80
6.30
0.22835 0.24803
y
-
0.10
θ
0
o
8
o
0
o
0.00394
8
o
C
Rev.A.01
11
www.ame.com.tw
E-Mail: [email protected]
Life Support Policy:
These products of AME, Inc. are not authorized for use as critical components in life-support
devices or systems, without the express written approval of the president
of AME, Inc.
AME, Inc. reserves the right to make changes in the circuitry and specifications of its devices and
advises its customers to obtain the latest version of relevant information.
 AME, Inc. , December 2007
Document: ORT6513-DS5107-A.01
Corporate Headquarter
U.S.A. (Subsidiary)
AME, Inc.
Analog Microelectronics, Inc.
2F, 302 Rui-Guang Road, Nei-Hu District
Taipei 114, Taiwan.
Tel: 886 2 2627-8687
Fax: 886 2 2659-2989
3100 De La Cruz Blvd., Suite 201
Santa Clara, CA. 95054-2438
Tel : (408) 988-2388
Fax: (408) 988-2489