AME5125 High Efficiency 500KHz Step-Up Converter

AME
High Efficiency 500KHz
Step-Up Converter
AME5125
n General Description
n Features
l High Efficiency Synchronous Boost Converter
l Internal Low RDS(ON) Power MOSFETs
H: 50mΩ(PMOS) / L: 50mΩ(NMOS) Typical
l Operating (Input) Range: 2.7V ~ 5.5V
l Up to 5.5V Output Voltage
l 500KHz Switching Frequency
l Provide High Efficiency at Light Loading
l Load Disconnect During Shutdown
l Adjust Peak Switch Current
l Short Circuit into Hiccup Mode
l Internal Soft Start
l Integrated Over-Voltage Protection
l Thermal Shutdown
l All AME's Lead Free Products Meet RoHS
Standards
The AME5125 is a high-performance current mode synchronous boost converter with integrated Power MOSFETs
which on-resistance of internal main switch is only 50mΩ
and rectifier switch resistance is 50mΩ to maintain high
efficiency in heavy load conditions that supports switch
peak current of up to 5.5A. The integrated circuit supports an input voltage range of 2.7V to 5.5V.
The converter can be disabled to minimize battery drain.
During shutdown, the load (VOUT) is completely disconnected from the battery (VIN). Additional functions include an internal soft-start function in order to easy inrush current control. The circuit protection includes Over
Voltage Protection and Thermal Shutdown to prevent device failure under the "Worst" of operating conditions.
This device is available in SOP-8/PP with exposed pad
for low thermal resistance.
n Function Diagram
n Applications
l Battery Bank
l Portable Devices
EN
L1
2.2uH
VOUT
VIN
C1
10uF
AME5125
OFF
Rev.P01
NC
R1
806K
C2
22uF
C3
22uF
EN
PGND
Device
Control
VREF
PWM
EA
FB
R2
110K
EN
AGND
VOUT
Current
SENSE
Control
Logic
5V
FB
ISET
ON
VIN
C4
SW
VOUT
Oscillator
n Typical Application
Input
Well Switch
SW
OCP
Loop
Compensation
AGND
ISET
PGND
RISET
110K
1
AME
High Efficiency 500KHz
Step-Up Converter
AME5125
n Pin Configuration
SOP-8/PP
Top View
8
7
6
AME5125
1. EN
2. PGND
3. VIN
4. SW
5. VOUT
6. AGND
7. FB
8. ISET
5
GND
1
2
3
4
* Die Attach:
Conductive Epoxy
n Pin Description
2
Pin Number
Pin Name
Pin Description
1
EN
2
PGND
3
VIN
Input Voltage
4
SW
Switching Node.
5
VOUT
Output Voltage.
6
AGND
Analog Ground.
7
FB
Feedback Input.
8
ISET
9
Exposed Pad
Enable Input. When EN is floating, the device will be turn off.
Power Ground.
Switch Current Limit Adjustable Pin, Connect a Resistor to GND.
Power Ground.
Rev.P01
AME
High Efficiency 500KHz
Step-Up Converter
AME5125
n Ordering Information
AME5125 - x x x xxx
Output Voltage
Number of Pins
Package Type
Pin Configuration
Pin Configuration
A
(SOP-8/PP)
Rev.P01
1. EN
2. PGND
3. VIN
4. SW
5. VOUT
6. AGND
7. FB
8. ISET
Package Type Number of Pins
Z: SOP/PP
A: 8
Output Voltage
ADJ: Adjustable
3
AME
High Efficiency 500KHz
Step-Up Converter
AME5125
n Absolute Maximum Ratings
Parameter
Maximum
Unit
Input Voltage
-0.3 to +7
V
Switch Voltage
0.3 to +7
V
All Other Pins
-0.3 to +7
V
Electrostatic Discharge (HBM)
2000
V
Electrostatic Discharge (MM)
200
V
Electrostatic Discharge (CDM)
1000
V
Junction Temperature
150
o
C
-65 to +150
o
C
Storage Temperature Range
n Recommended Operating Conditions
Parameter
Symbol
Rating
Unit
VIN
2.7~5.5
V
VOUT
3.3 to 5.5
V
Junction Temperature Range
TJ
-40 to +125
o
C
Ambient Temperature Range
TA
-40 to +85
o
C
Input Voltage
Output Voltage
n Thermal Information
Parameter
Package
Die Attach
Thermal Resistance
(Junction to Case)
Thermal Resistance
(Junction to Ambient)
Internal Power Dissipation
Solder Iron (10 Sec)**
4
Symbol
Maximum
θJC
19
Unit
o
SOP-8/PP
Conductive Epoxy
θJA
84
PD
1450
350
C/W
mW
o
C
Rev.P01
AME
High Efficiency 500KHz
Step-Up Converter
AME5125
n Electrical Specifications
Typical values VIN=3.7V, VOUT=5V with typical TA=25oC, unless otherwise specified.
Parameter
Symbol
Test Condition
Min
Typ
Max
Units
VIN
2.7
5.5
V
Output Voltage Operating Range
VOUT
3.3
5.5
V
Feedback Voltage
VFB
0.588
0.6
0.612
V
Switching Frequency
FSW
400
500
KHz
Max. Duty Cycle
DMAX
90
%
µA
Input Voltage Operating Range
Quiescent Current
VOUT IQ
No switching
60
Shutdown Current
ISD
VEN=0V
0.1
1
uA
Rectifying Switch on Resistance
RDS(ON)_P
50
mΩ
Main Switch on Resistance
RDS(ON)_N
50
mΩ
UVLO Rising Threshold Voltage
VUVLOR
VIN Voltage
2.6
V
UVLO Falling Threshold Voltage
VUVLOF
VIN Voltage
2.4
V
RISET
RL=110 KΩ, VOUT>VIN
5.5
A
Switch Current Limit
EN Logic-High Voltage
VIH
EN Logic-Low Voltage
VIL
EN Input Current
IEN
Output OVP
Thermal Shutdown
Thermal Shutdown Hysteresis
Rev.P01
VOVP
TSD
TSDHYS
4.0
1.4
V
0.6
V
0.1
uA
VFB=0.6V
1.16xVFB
V
VOUT=5V
6
V
150
o
C
20
o
C
5
AME
AME5125
n Application Information
High Efficiency 500KHz
Step-Up Converter
VOUT=0.6x(1+R1/R2)
VOUT
Over Voltage Protection
The AME5125 has output over-voltage protections. The
thresholds output OVP circuit minimum 116% x VOUT,
respectively. Once the output voltage is higher than the
threshold, the NMOS driver is turned off. When the output voltage drops lower than the threshold, the NMOS
driver will be enabled again.
0.6V
R1
EA
FB
R2
Inductor Selection
The inductor is required to supply current to the load
while being driven by the switched input voltage. It will
result in less ripple current that will in turn result in lower
output ripple voltage. In addition minimum inductance value
is proportional to the operating frequency. Make sure
that the peak inductor current is below the maximum
switch current limit. Determine inductance is to allow
the peak-to-peak ripple current to be approximately 30%
of the maximum load current. The inductance value can
be calculated by:
L=(VIN/VOUT)2 (VOUT-VIN) / FSW x IOUT x 40%
FSW is the switching frequency IOUT is the max output
current.
Over Current Protection
The AME5125 cycle-by-cycle limits the peak inductor
current to protect NMOS driver. The NMOS driver will
turn off when switching current reaches OCP level that
can be set by external RISET.
Thermal Shutdown
The AME5125 protects itself from overheating with an
internal thermal shutdown circuit. If the junction temperature exceeds the thermal shutdown trigger point, the
NMOS driver is turned off. The part is restarted when the
junction temperature drops 20oC below the thermal shutdown trigger point.
Setting the Output Voltage
Input Capacitor CIN
The input current to the boost converter is discontinuous, therefore a capacitor is required to supply the AC
current while maintaining the DC input voltage. Use low
ESR capacitors for the best performance. Ceramic capacitors are preferred.
The ripple current through input capacitor is calculated
was list below:
ICIN_RMS=VINx(VOUT-VIN)/3.46xLxFSWxVOUT
The input capacitor is selected to handle the input ripple
noise requirements. Suggesting to use X5R or X7R grade
ceramic capacitor.
Output capacitor COUT
The outpour capacitor is required to maintain the DC
output voltage. Ceramic, tantalum, or low ESR electrolytic capacitors are recommended. The Low ESR capacitors are preferred to keep the lower output voltage
ripple. It's recommended X5R or X7R ceramic capacitor
with enough voltage rating.
The Enable Operation
Pulling the EN pin low (<0.6V) will shutdown the device. At the shutdown mode, the AME5125 output drop
to zero in addition only below 1uA standby current. When
EN Pin >1.4, the AME5125 will turn on device. If EN Pin
floating the AME5125 into shutdown mode.
The output voltage is using a resistive voltage divider
connected from the output voltage to FB. It divides the
output voltage down to the feedback voltage by the ratio:
6
Rev.P01
AME
High Efficiency 500KHz
Step-Up Converter
AME5125
n Characterization Curve
Output Voltage Ripple
V IN
(2V/Div)
V SW
(5V/Div)
IL
(200mA/Div)
V OUT
(50mV/Div)
Output Voltage Ripple
V IN
(2V/Div)
V SW
(5V/Div)
C1
C2
VIN=3.2V, IOUT=0mA
IL
(1A/Div)
V OUT
(100mV/Div)
C4
C3
Time(2ms/Div)
C1
C2
VIN=3.2V, IOUT=1000mA
C4
C3
Time(1µs/Div)
Output Voltage Ripple
RISET vs Current Limit
8
7.5
IL
(2A/Div)
VOUT
(200mV/Div)
7
C1
C2
Current Limit (A)
VIN
(2V/Div)
VSW
(5V/Div)
6
5.5
5
4.5
4
VIN=3.2V, IOUT=2000mA
C4
6.5
3.5
C3
3
Time(1µs/Div)
90
110
130
150
170
190
210
230
250
RISET(KΩ)
Efficiency
100
Efficiency (%)
90
80
70
VIN=3.7 VOUT=5V
60
50
Rev.P01
0.0
0.5
1.0
Current (A)
1.5
2.0
7
AME
High Efficiency 500KHz
Step-Up Converter
AME5125
n Characterization Curve (Contd.)
Load Transient
Load Transient
VIN=3.7V, IOUT=500~1000mA
VIN=4.2V, IOUT=500~1000mA
VOUT
(500mV/Div)
V OUT
(500mV/Div)
IL
(1A/Div)
IL
(1A/Div)
Time(1ms/Div)
Time(1ms/Div)
Load Transient
Load Transient
VIN=3.7V, IOUT=500~2000mA
V OUT
(500mV/Div)
IL
(2A/Div)
IL
(2A/Div)
Time(1ms/Div)
8
VIN=4.2V, IOUT=500~2000mA
V OUT
(500mV/Div)
Time(1ms/Div)
Rev.P01
AME
High Efficiency 500KHz
Step-Up Converter
AME5125
n Characterization Curve (Contd.)
Power ON
V EN
C1
(5V/Div)
VIN=4.2V, IOUT=1000mA
Power ON
V EN
C1
(5V /Div)
V SW
C2
(5V/Div)
VSW
C2
(5V /D iv)
V OUT
C3
(2V/Div)
VOUT
C3
(2V /Div)
IL
C4
(2A/Div)
V EN
C1
(5V/Div)
IL
(500m A /Div) C 4
Time(2ms/Div)
Time(1ms/Div)
Power OFF
Power OFF
VIN=4.2V, IOUT=1000mA
VEN
C1
(5V/Div)
V SW
C2
(5V/Div)
VSW
C2
(5V/Div)
VOUT
C3
(2V/Div)
VOUT
C3
(2V/Div)
IL
C4
(1A/Div)
IL
(500mA/Div) C4
Time(500µs/Div)
Rev.P01
VIN=3V, IOUT=0mA
VIN=3V, IOUT=0mA
Time(2ms/Div)
9
AME
High Efficiency 500KHz
Step-Up Converter
AME5125
n Tape and Reel Dimension
SOP-8/PP
P0
PIN 1
W
AME
AME
P
Carrier Tape, Number of Components Per Reel and Reel Size
Package
Carrier Width (W)
Pitch (P)
Pitch (P0)
Part Per Full Reel
Reel Size
SOP-8/PP
12.0±0.1 mm
8.0±0.1 mm
4.0±0.1 mm
2500pcs
330±1 mm
n Package Dimension
SOP-8/PP
TOP VIEW
SIDE VIEW
D1
E1
E2
E
L1
C
PIN 1
D
e
10
A1
FRONT VIEW
A
A2
b
SYMBOLS
MILLIMETERS
INCHES
MIN
MAX
MIN
MAX
A
1.350
1.750
0.053
0.069
A1
0.000
0.150
0.000
0.006
A2
1.350
1.600
0.053
0.063
C
0.100
0.250
0.004
0.010
E
3.750
4.150
0.148
0.163
E1
5.700
6.300
0.224
0.248
L1
0.300
1.270
0.012
0.050
b
0.310
0.510
0.012
0.020
D
4.720
5.120
0.186
0.202
e
1.270 BSC
0.050 BSC
θ
0o
8o
0o
8o
E2
2.150
2.513
0.085
0.099
D1
2.150
3.402
0.085
0.134
Rev.P01
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. , February 2015
Document: A030A-DS5125-A.01
Corporate Headquarter
AME, Inc.
2F, 302 Rui-Guang Road, Nei-Hu District
Taipei 114, Taiwan, R.O.C
Tel: 886 2 2627-8687
Fax: 886 2 2659-2989