AME5249A/Buck Converter

AME
AME5249A
n General Description
The AME5249A is a fixed-frequency current mode synchronous PWM step down converter that is capable of
delivering 600mA output current while achieving peak efficiency of 95%. Under light load conditions, the AME5249A
operates in a power saving mode that consumes just
around 20µA of supply current, maximizing battery life in
portable applications. The AME5249A operates with a
fixed frequency of 1.5MHz, minimizing noise in noisesensitive applications and allowing the use of small external components. The AME5249A is an ideal solution
for applications powered by Li-Ion batteries or other portable applications that require small board space.
The AME5249A is available in a variety of fixed output
voltage options, 1.0V, 1.2V, 1.3V, 1.5V, 1.8V, 2.5V, 2.7V,
2.8V, and 3.3V, and is also available in an adjustable
output voltage version capable of generating output voltages from 0.6V to V IN . The AME5249A is available in the
tiny 5-pin SOT-25 and TSOT-25 package.
1.5MHz, 600mA
Synchronous Buck Converter
n Applications
l Blue Tooth Headsets
l Portable Audio Players
l Mobile Phones
l Wireless and DSL Modems
l Digital Still Cameras
l Portable Instruments
n Typical Application
L
4.7µH
VIN
2.5V to 5.5V
IN
C IN
4.7µF
AME5249A
EN
n Features
V OUT
SW
COUT
10µF
OUT
GND
l High Efficiency - Up to 95%
l Very Low 20µA Quiescent Current
l Guaranteed 600mA Output Current
Figure 1. Fixed Voltage Regulator
l 1.5MHz Constant Frequency Operation PWM
l Internal Synchronous Rectifier Eliminates
Schottky Diode
l Adjustable Output Voltages From 0.6V to VIN
l Fixed Output Voltage Options Available 1.0V,
1.2V, 1.3V, 1.5V, 1.8V, 2.5V, 2.7V, 2.8V and
L
4.7 µH
VIN
2.5V to 5.5V
IN
CIN
4.7µF
SW
AME5249A
EN
3.3V
l 100% Duty Cycle Low-Dropout Operation
VOUT
1.8V/600mA
FB
GND
C1
22pF
R1
887K
R2
442K
COUT
10µF
l 0.1µA Shutdown Current
l Require Tiny Capacitors and Inductor
l Tiny SOT-25 and TSOT-25 Package
Figure 2. Adjustable Voltage Regulator
l All AME's Lead Free Products Meet RoHS
Standards
Rev.A.01
1
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Function Block Diagram
EN
VIN
Current
Limit
Comparaotr
1.5 MHz
Oscillator
OSC
Current
Sense
Bandgap
UVLO
Slope
Comp
FB
S
+
EA
Fixed Output
See Note
+
COMP
-
R
Q
Logic
Control
SW
Driver
Thermal
Shudown
+
-
COMP
GND
Figure 3
Note: For the fixed output version the internal feedback divider is actived.
For the adjustable version the internal feedback divider is disabled, and the FB pin is directly connected to
the internal EA amplifer.
2
Rev.A.01
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Pin Configuration
SOT-25/TSOT-25
Top View
5
4
AME5249A-AEVxxx
1. EN
2. GND
AME5249A
3. SW
4. IN
1
2
3
5. FB/OUT
Die Attach:
Conductive Epoxy
Rev.A.01
3
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Pin Description
Pin Number
Pin Name
Pin Description
1
EN
Enable Control Input.
The enable pin is an active high control. Tie this pin above 1.4V to enable the
device. Tie this pin below 0.4V to shut down the device. In shutdown, all
function are disabled. Do not leave EN pin floating.
2
GND
Ground
Tie directly to ground plane.
3
SW
Switch Node Connection to Inductor.
4
IN
5
4
FB/OUT
Input Supply Voltage Pin.
Bypass this pin with a capacitor as close to the device as possible
FB:Output voltage Feedback input.
Set the output voltage by selecting values for R1 and R2 using: R1 = R2
(VOUT/0.6V -1)
Connect the ground of the feedback network to an AGND (Analog Ground)
plane which should be tied directly to the GND pin.
OUT:Output Pin
Rev.A.01
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Ordering Information
AME5249A - x x x xxx x
Special Feature
Output Voltage
Number of Pins
Package Type
Pin Configuration
Pin
Configuration
A
(SOT-25)
(TSOT-25)
Rev.A.01
1. EN
2. GND
3. SW
4. IN
5. FB/OUT
Package
Type
E: SOT-2X
Number of
Pins
V:
5
Output Voltage
ADJ:
100:
120:
130:
150:
180:
250:
270:
280:
330:
Adjustable
1.0V
1.2V
1.3V
1.5V
1.8V
2.5V
2.7V
2.8V
3.3V
Special Feature
N/A: SOT-25
L: TSOT-25 (Low Profile)
5
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Available Options
Part Number
Marking*
Output Voltage
Package
Operating Ambient
Temperature Range
AME5249A-AEVADJ
CBNMXX
ADJ
SOT-25
-40OC to +85OC
Note:
1. The first 3 places represent product code. It is assigned by AME such as CBN.
2. A bar on top of first letter represents Green Part such as CBN.
3. The last 3 places MXX represent Marking Code. It contains M as date code in "month", XX as LN code and
that is for AME internal use only. Please refer to date code rule section for detail information.
4. Please consult AME sales office or authorized Rep./Distributor for the availability of output voltage and package
type.
6
Rev.A.01
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Absolute Maximum Ratings
Parameter
Symbol
Maximum
Unit
VIN
-0.3 to +6.5
V
VEN, VFB
-0.3 to VIN
V
VSW, VOUT
-0.3 to VIN
V
Input Voltage
EN, FB
SW, VOUT
B*
ESD Classification
Caution: Stress above the listed absolute maximum rating may cause permanent damage to the device.
* HBM B:2000V~3999V
n Recommended Operating Conditions
Parameter
Symbol
Rating
Unit
Input Supply Voltage
VIN
-0.3 to 6.5
V
Ambient Temperature Range
TA
-40 to +85
Junction Temperature Range
TJ
-40 to +125
Storage Temperature Range
TSTG
-65 to +150
o
C
n Thermal Information
Parameter
Package
Die Attach
Thermal Resistance
(Junction to Case)
Symbol
Maximum
θJC
81
Unit
o
Thermal Resistance
(Junction to Ambient)
SOT-25*
TSOT-25
Conductive Epoxy
Internal Power Dissipation
Solder Iron (10 Sec)**
θJA
260
PD
400
350
C/W
mW
o
C
* Measure θJC on backside center of molding compund if IC has no tab.
** MIL-STD-202G 210F
Rev.A.01
7
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Electrical Specifications
VIN=3.6V, EN=VIN, TA = 25OC, unless otherwise noted
Parameter
Input Voltage
Output Voltage Accuracy
(for every fixed output voltage)
Symbol
Test Condition
VIN
∆VOUT
VIN =2.5 to 5.5V, VOUT=1.0V~1.8V
PWM Mode
VIN=VOUT+ ∆V to 5.5V (Note 1)
VOUT=2.5V~3.3V, PWM Mode
Output Voltage Accuracy (Adj)
∆VOUT
Adjustable Output Range
VOUT
Feedback Voltage
VFB
Feedback Pin Bias Current
IFB
VIN=VOUT+ ∆V to 5.5V (Note 1)
PWM Mode
TA=25oC
o
o
TA=-40 C to +85 C
Min
Max
Units
2.5
5.5
V
-3
3
-3
3
-3
3
V FB
VIN0.2
0.588
0.6
0.612
0.585
0.6
0.615
-50
VFB=0.5V or VOUT=90%,
Quiescent Current
IQ
Typ
IOUT=0A
VFB=0.62V or VOUT=103%,
IOUT=0A
50
300
400
20
35
0.1
1
Shutdown Current
ISHDN
VEN =0V, VIN=4.2V
Reference Voltage Line Regulation
∆VFB
2.5≦ V IN ≦ 5.5V
0.4
Output Voltage Line Regulation
REGLINE
2.5≦ V IN ≦ 5.5V
0.4
Output Voltage Load Regulation
REGLOAD
IOUT=100mA to 600mA
0.5
High-side Switch On-Resistance
RDS,ON,HI
ISW =100mA
0.4
0.6
Low-side Switch On-Resistance
RDS,ON,LO
ISW =-100mA
0.35
0.5
Switch Current Limit
ISW,CL
VIN =3V, VOUT=1.2V
Switch Leakage Current
ISW,LK
Switch Frequency
fOSC
1
V EN =0V, VSW =0V or 3.6V,
VIN =3.6V
VFB=0.6V or VOUT=100%
1.2
%
V
V
nA
µA
%/V
%
1.25
Ω
A
0.01
1
1.5
1.8
µA
MHz
Short Circuit Oscillator Frequency
Maximum Duty Cycle
8
fOSC,SCR
DMAX
VFB=0V or VOUT=0V
0.21
100
%
Rev.A.01
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Electrical Specifications (Contd.)
VIN=3.6V, EN=VIN, TA = 25OC, unless otherwise noted
Symbol
Test Condition
Min
Typ
Max
Input Undervoltage Lockout
VUVLO
VIN Rising
2
2.15
2.3
Input Undervoltage Lockout
Hysteresis
VUVLO,HYST
Parameter
Enable High (Enabled the Device)
VEN,HI
Enable Low (Shutdown the Device)
VEN,LO
EN Input Current (Enable the Device)
0.1
Units
V
1.4
0.4
IEN
0.01
Thermal Shutdown Temperature
OTP
Shutdown, temperature increasing
160
Thermal Shutdown Hysteresis
OTH
Restore, temperature increasing
30
1
µA
o
C
Note 1: ∆V=IOUT x RDS.ON.HI
Rev.A.01
9
AME
AME5249A
1.5MHz, 600mA
Synchronous Buck Converter
n Detailed Description
Main Control Loop
The AME5249A utilizes a fixed-frequency,current-mode
PWM control scheme combined with fully-integrated
power MOSFETs to produce a compact and efficient stepdown DC-DC solution. During normal operation the highside MOSFET turns on each cycle and remains on until
the current comparator turns it off. At this point the lowside MOSFET turns on and remains on until either the
end of the switching cycle or until the inductor current
approaches zero. The error amplifier adjusts the current
comparator's threshold according to the load current to
ensure that the output voltage remains in regulation.
Current Limit Protection
The AME5249A has current limiting protection to prevent excessive stress on itself and external components.
The internal current limit comparator will disable the
power device at a switch peak current limit. Under extreme overloads, such as short-circuit conditions, the
AME5249A reduces it's oscillator frequency to around
210KHz to allow further inductor current reduction and to
minimize power dissipation.
Under Voltage Protection
Light Load Power Saving Mode Operation
The AME5249A is capable of Power Saving Mode Operation in which the internal power MOSFETs operate
intermittently based on load demand.
In Power Saving Mode operation, the peak current of
the inductor is set to a certain value which increases as
the input voltage increases, such as 260mA for 3.6V input voltage and 340mA for 5.5V input voltage, approximately. Each switching event can last from a single cycle
at very light loads to few cycles within the active intervals
at moderate loads. Between these switching intervals,
the unneeded circuitry are turned off, reducing the quiescent current to 20µA. In this turned off state, the load
current is being supplied solely from the output capacitor. As the output voltage droops, the internal comparator
trips and turns on the circuits. This process repeats at a
rate depends on the load demand.
Dropout Operation
As the input supply voltage decreases to a value approaching the output voltage, the duty cycle increases
toward the maximum on-time. Further reduction of the
supply voltage forces the main switch to remain on for
more than one cycle until it reaches 100% duty cycle.
The output voltage will then be determined by the input
voltage minus the voltage drop across the P-channel
MOSFET and the inductor.
10
The AME5249A has an UVP comparator to turn the power
device off in case the input voltage or battery voltage is
too low.
Soft Start
The AME5249A integrates a soft start function that prevents input inrush current and output overshoot during
start-up. During start-up the switch current limit is increased in steps. The start-up time thereby depends on
the output capacitor and load current demanded at startup. Typical start-up times with a 10µF output capacitor,
3.6V input voltage and 1.5V output voltage, for 250mA
load is 120µs.
Thermal Shutdown
The device protects itself from overheating with an internal thermal shutdown circuit. If the junction temperature exceeds the thermal shutdown trip point, the device
turns off. The part is restarted when the junction temperature drops 30oC below the thermal shutdown trip point.
Rev.A.01
AME
AME5249A
1.5MHz, 600mA
Synchronous Buck Converter
n Application Information
The typical AME5249A application circuit is shown in
Figure1. The external component selection is driven by
the load requirement.
Inductor Selection
Although the inductor does not influence the operating
frequency, the inductor value has a direct effect on ripple
current. The inductor ripple current △IL decreases with
higher inductance and increases with higher VIN or VOUT:
∆I L =
VIN − VOUT VOUT
×
L × f SW
VIN
The inductor must have a saturation (incremental) current rating equal to the peak switch-current limit. For high
efficiency, minimize the inductor's DC resistance.
The inductor value also has an effect on Power Saving
Mode operation. Lower inductor values (higher ripple current) will cause the transition from PWM to Power Saving
Mode to occur at lower load currents, which can cause a
dip in efficiency in the upper range of low current operation.
Inductor Core Selection
Once the value for L is known, the type of inductor
must be selected. High efficiency converters generally
cannot afford the core loss found in low cost powdered
iron cores, forcing the use of more expensive ferrite or
mollypermalloy cores. Actual core loss is independent of
core size for a fixed inductor value but it is very dependent on the inductance selected. As the inductance increases, core losses decrease. Unfortunately, increased
inductance requires more turns of wire and therefore copper losses will increase. Ferrite designs have very low
core losses and are preferred at high switching frequencies, so design goals can concentrate on copper loss
and preventing saturation. Ferrite core material saturates
"hard", which means that inductance collapses abruptly
when the peak design current is exceeded. This result in
an abrupt increase in inductor ripple current and consequent output voltage ripple. Do not allow the core to saturate! Different core materials and shapes will change the
size/current and price/current relationship of an inductor.
Rev.A.01
Toroid or shielded pot cores in ferrite or permalloy materials are small and don't radiate energy but generally
cost more than powdered iron core inductors with similar
characteristics. The choice of which style inductor to use
mainly depends on the price vs. size requirements and
any radiated field/EMI requirements.
Input Capacitor Selection
In continuous mode, the source current of the main
power MOSFET is a square wave of duty cycle VOUT/VIN.
To prevent large voltage transients, a low ESR input capacitor sized for the maximum RMS current must be used.
The input filter capacitor supplies current to the main power
MOSFET of AME5249A in the first half of each cycle and
reduces voltage ripple imposed on the input power source.
A ceramic capacitor's low ESR provides the best noise
filtering of input voltage spikes due to this rapidly changing current. Select a capacitor with sufficient ripple current rating.
The input capacitor's maximum RMS capacitor current
is given by:
I RMS ≈ I MAX
(VIN − VOUT )VOUT
VIN
Where the maximum average output current IMAX equals
the peak current ILIM minus half peak-to-peak ripple current, IMAX=ILIM-△IL/2.
This formula has a maximum at VIN=2VOUT, where IRMS
=IOUT/2. This simple worst-case condition is commonly
used for design because even significant deviations do
not offer much relief. Note that ripple current ratings from
capacitor manufacturers are often based on only 2000
hours of life which makes it advisable to further derate the
capacitor, or choose a capacitor rated at a higher temperature than required. Several capacitors may also be
paralleled to meet size or height requirements in the design.
11
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
Output Capacitor Selection
Thermal Considerations
The selection of COUT is driven by the required effective
series resistance (ESR). Typically, once the ESR requirement for COUT has been met, the RMS current rating
generally far exceeds the IRIPPLE(P-P) requirement. The
output ripple VOUT is determined by
In most applications the AME5249A does not dissipate much heat due to its high efficiency. But, in applications where the AME5249A is running at high ambient
temperature with low supply voltage and high duty cycles,
such as in dropout, the heat dissipated may exceed the
maximum junction temperature of the part. If the junction temperature reaches approximately 160OC, both
power switches will be turned off and the SW node will
become high impedance. To avoid the AME5249A from
exceeding the maximum junction temperature, the user
will need to do some thermal analysis. The goal of the
thermal analysis is to determine whether the power dissipated exceeds the maximum junction temperature of
the part. The temperature rise is given by:
∆VOUT ≈ ∆I L ( ESR +
1
8COUT f SW
)
Where fSW =operating frequency, C OUT=output capacitance and △IL=ripple current in the inductor. For a fixed
output voltage, the output ripple is highest at maximum
input voltage since △IL increases with input voltage.
At the light load current, the device operates in Power
Saving Mode, and the output voltage ripple is independent of the value of the output capacitor. The output ripple
is set by the internal comparator thresholds and is also
affected by the feedback capacitor C1 in figure2. Large
capacitor values can decrease the output ripple, usually
a 22pF capacitor is sufficient for most applications.
TR = ( PD) × θ JA
Where PD is the power dissipated by the regulator and
θJA is the thermal resistance from the junction of the die
to the ambient temperature.
When the input and output ceramic capacitors are chosen, choose the X5R or X7R dielectric formulations. These
dielectrics have the best temperature and voltage characters have the best temperature and voltage characteristics of all the ceramics for a given value and size.
Output Voltage Setting
In the adjustable version, the output voltage is set by a
resistor divider according to following formula:
VOUT = 0.6V × (1 +
R2
)
R1
The external resistor divider is connected to the output.
12
Rev.A.01
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Typical Application
L
4.7µH
VIN
2.5V to 5.5V
IN
CIN
4.7µF
VOUT
1.2V/600mA
SW
AME5249A
EN
IN
C1
22pF
FB
R1
442K
R2
442K
GND
COUT
10µF
L
4.7µH
IN
CIN
4.7µF
CIN
4.7µF
VOUT
3.3V/600mA
SW
AME5249A
EN
FB
GND
Figure 4. AME5249A with 1.2V Output
VIN
2.5V to 5.5V
L
4.7µH
VIN
3.6V to 5.5V
C1
22pF
R1
887K
R2
196K
COUT
10µF
Figure 7. AME5249A with 3.3V Output
VOUT
1.5V/600mA
SW
AME5249A
EN
C1
22pF
R1
475K
COUT
10µF
R2
316K
FB
GND
Figure 5. AME5249A with 1.5V Output
L
4.7µH
VIN
2.7V to 5.5V
IN
CIN
4.7µF
VOUT
2.5V/600mA
SW
AME5249A
EN
FB
GND
C1
22pF
R1
887K
R2
280K
COUT
10µF
Figure 6. AME5249A with 2.5V Output
Rev.A.01
13
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Characterization Curve
Efficiency vs Output Current
Efficiency vs Output Current
100
100
90
90
80
VIN=4.2V
70
Efficiency(%)
Efficiency(%)
VIN=2.7V
VIN=3.6V
80
60
50
40
30
60
VOUT=2.5V
10
0.1
40
1
10
100
20
Oscillator Frequency(MHz)
0.610
0.605
0.600
0.595
0.590
-15
+10
+35
+60
+85
1.65
1000
VIN=3.6V
1.60
1.55
1.50
1.45
1.40
1.35
1.30
-40
+110
Temperature(oC)
-15
+10
+35
+60
+85
+110
Temperature(oC)
Oscillator Frequency vs Supply Voltage
Quiescent Current vs Input Voltage
50
1.70
45
1.65
Quiescent Current (µA)
Oscillator Frequency(MHz)
100
1.70
VIN=3.6V
0.585
14
10
Oscillator Frequency vs Temperature
0.620
1.60
1.55
1.50
1.45
1.40
40
VIN=3.6V
VOUT =1.8V
IOUT =0A
35
30
25
20
15
10
5
1.35
1.30
2.5
1
Output Current(mA)
Reference Voltage vs Temperature
Reference Voltage (V)
VOUT=1.5V
10
0.1
1000
Output Current(mA)
0.580
-40
VIN=4.2V
50
30
20
0.615
VIN=2.7V
VIN=3.6V
70
3.5
VIN(V)
4.5
5.5
0
2.5
3.5
4.5
5.5
VIN(V)
Rev.A.01
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Characterization Curve (Contd.)
Quiescent Current vs Temperature
Light Load Mode
50
Quiescent Current (µA)
45
40
V IN=3.6V
V OUT=1.8V
IOUT =0A
VSW
5V /Div
35
30
VOUT
100mV/Div
AC COUPLED
25
20
15
IL
200mA/Div
10
5
0
-40
-15
+10
+35
+60
+85
VIN=3.6V
VOUT=1.8V
IOUT=50mA
+110
Temperature( oC)
Load Step
Load Step
VOUT
100mV/Div
AC COUPLED
VOUT
100mV/Div
AC COUPLED
IL
500mA/Div
IL
500mA/Div
IOUT
500mA/Div
IOUT
500mA /Div
VIN=3.6V
20µS/Div
VOUT =1.8V
IOUT =50mA to 600mA
V IN=3.6V
20µS/Div
V OUT=1.8V
IOUT =0mA to 600mA
Load Step
Load Step
VOUT
100mV/Div
AC COUPLED
VOUT
100mV/Div
AC COUPLED
IL
500mA/Div
IL
500mA/Div
IOUT
500mA/Div
IOUT
500mA/Div
Rev.A.01
5µS/Div
VIN=3.6V
20µS/Div
VOUT =1.8V
IOUT =100mA to 600mA
VIN=3.6V
20µS/Div
VOUT=1.8V
IOUT=200mA to 600mA
15
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Characterization Curve (Contd.)
Stead State Test
RDS(ON) vs Temperature
0.7
VIN=3.6V
VIN
200mV/Div
AC COUPLED
0.6
High-Side Switch
RDS(ON) (Ω)
0.5
VOUT
20mV/Div
IL
100mA/Div
0.4
Low-Side Switch
0.3
0.2
VSW
2V /Div
AC COUPLED
0.1
-40
VIN=3.6V
VOUT=1.8V
IOUT=300mA
-15
+10
1µS/Div
+35
+60
+85
+110
Temperature(o C)
RDS(ON) vs Input Voltage
Output Voltage vs Output Current
1.87
0.7
1.86
0.6
High-Side Switch
0.5
RDS(ON) (Ω)
Output Voltage(V)
1.85
0.4
0.3
Low-Side Switch
1.84
1.83
1.82
1.81
1.80
1.79
0.2
1.78
0.1
2.5
1.77
3.5
4.5
0
5.5
100
200
300
400
500
Input Voltage(V)
Output Current(mA)
Start Up From EN
Current Limit vs VIN
600
1.9
VIN
5V/Div
1.8
Current Limit(A)
1.7
EN
5V/Div
VOUT
2V/Div
1.6
1.5
1.4
1.3
1.2
1.1
1.0
IL
500mA/Div
0.9
VOUT=1.2V
0.8
16
VIN=5V
VOUT=3.3V
IOUT=600mA
40µS/Div
0.7
2.5
2.8
3.1
3.4
3.7
4.0
VIN(V)
4.3
4.6
4.9
5.2
5.5
Rev.A.01
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Characterization Curve (Contd.)
Current Limit vs Temperature
2.10
2.00
1.90
Current Limit(A)
1.80
1.70
1.60
1.50
1.40
VIN=3.3V
1.30
1.20
VIN=3.6V
VIN=5.0V
1.10
1.00
0.90
VOUT=1.2V
0.80
0.70
-40
-25
-10
+5
+20 +35 +50 +65 +80 +95 +110 +125
Temperature(oC)
Rev.A.01
17
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Date Code Rule
Month Code
1: January 7: July
2: February 8: August
3: March
9: September
4: April
A: October
5: May
B: November
6: June
C: December
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
A
Marking
A
M
A
M
A
M
A
M
A
M
A
M
A
M
A
M
A
M
A
M
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Year
xxx0
xxx1
xxx2
xxx3
xxx4
xxx5
xxx6
xxx7
xxx8
xxx9
n Tape and Reel Dimension
SOT-25
P
W
AME
AME
PIN 1
Carrier Tape, Number of Components Per Reel and Reel Size
18
Package
Carrier Width (W)
Pitch (P)
Part Per Full Reel
Reel Size
SOT-25
8.0±0.1 mm
4.0±0.1 mm
3000pcs
180±1 mm
Rev.A.01
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Tape and Reel Dimension (Contd.)
TSOT-25
P
W
AME
AME
PIN 1
Carrier Tape, Number of Components Per Reel and Reel Size
Rev.A.01
Package
Carrier Width (W)
Pitch (P)
Part Per Full Reel
Reel Size
TSOT-25
8.0±0.1 mm
4.0±0.1 mm
3000pcs
180±1 mm
19
AME
1.5MHz, 600mA
Synchronous Buck Converter
AME5249A
n Package Dimension
SOT-25
Top View
Side View
SYMBOLS
D
INCHES
MIN
MAX
MIN
MAX
A
0.90
1.30
0.0354
0.0512
A1
0.00
0.15
0.0000
0.0059
b
0.30
0.55
0.0118
0.0217
D
2.70
3.10
0.1063
0.1220
E
1.40
1.80
0.0551
0.0709
E
θ1
H
MILLIMETERS
L
PIN 1
1.90 BSC
e
S1
e
H
2.60
0.1024
0
o
10
0.1181
0.0146 BSC
o
0o
0.95 BSC
10o
0.0374 BSC
A1
A
θ1
S1
3.00
0.37 BSC
L
Front View
0.0748 BSC
b
TSOT-25
Top View
Side View
SYMBOLS
D
MAX
MIN
MAX
A+A1
0.90
1.25
0.0354
0.0492
b
0.30
0.50
0.0118
0.0197
D
2.70
3.10
0.1063
0.1220
E
1.40
1.80
0.0551
0.0709
1.90 BSC
E
e
L
PIN 1
S1
H
2.40
θ1
S1
3.00
0
o
10
0.95BSC
0.0945
0.1181
0.0138BSC
o
0o
10 o
0.0374BSC
A1
A
Front View
0.07480 BSC
0.35BSC
L
e
INCHES
MIN
θ1
H
MILLIMETERS
b
20
Rev.A.01
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. , August 2011
Document: 3005-DS5249A-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