AME5287 Step-Down Converter

AME
AME5287
n General Description
The AME5287 is a Synchronous Rectified Step-Down
Converter with internal power MOSFETs. It achieves 3A
continuous output current over a wide switching frequency
range with excellent load and line regulation.
Current mode operation provides fast transient response
and eases of loop stabilization. Internal soft-start minimizes the inrush supply current at startup. The circuit
protection includes cycle-by-cycle current limiting, output short circuit frequency protection and thermal shutdown. In shutdown mode, the regulator reduces the current less than 1µA of supply current.
This device is available in SOP-8/PP ,DFN-8 package
with exposed pad for low thermal resistance.
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
n Typical Application
L
2.2µH
VIN
5V
IN
CIN
10µF
OFF ON
SW
R1
75KΩ
EN
AME5287
VOUT
3.3V
COUT
22µF
FB
COMP
C2
Optional
C1
680pF
R3
25KΩ
GND
FREQ
R2
24KΩ
RFREQ
18KΩ
Figure 1. 3.3V at 3A Step-Down Regulators.
n Features
l 3A Output Current
l Stable with Low ESR Output Ceramic
L
1.5µH
VIN
3V~5V
IN
Capacitors
l Pre-Regulator for Linear Regulators
l Up to 95% Efficiency
CIN
10µF
OFF ON
300KHz~2MHz
l Thermal Protection
R1
6KΩ
EN
AME5287
VOUT
1V
C OUT
22µF
FB
COMP
l Less than 1µA Shutdown Current
l Wide Switching Frequency Range from
SW
C2
Optional
C1
680pF
R3
8.2KΩ
GND
FREQ
R2
24KΩ
RFREQ
18KΩ
l Cycle-by-Cycle Over Current Protection
l Output Adjustable from 0.8V to VIN
Figure 2. 1V at 3A Step-Down Regulators.
l Short Circuit Protection
l Green Products Meet RoHS Standards
n Applications
l TV
l Distributed Power Systems
l Pre-Regulator for Linear Regulators
l Digital Cameras
Rev. A.01
1
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Functional Block Diagram
IN
CURRENT
SENSE
EN
ENABLE
CURRENT
LIMIT
UVLO
FREQ
OSC
SW
SLOPE
+
+
COMP
0.8V
VREF
+
EA
-
GND
SOFT
START
-
DRIVER
LOGIC
PWM
IRCMP
OTP
FB
SW
+
Short circuit
PGND
n Pin Configuration
DFN-8C
(3mmx3mmx0.75mm)
Top View
SOP-8/PP
Top View
8
7
6
5
AME5287-AZAADJ
8
7
6
5
1. COMP
1. COMP
2. GND
9
2
3
4
9
4. IN
5. SW
1
2. GND
AME5287
3. EN
AME5287
AME5287-AVAADJ
3. EN
4. IN
1
2
3
4
5. SW
6. SW
6. SW
7. FREQ
7. FREQ
8. FB
8. FB
9. GND (Exposed Pad)
9. GND (Exposed Pad)
* Die Attach:
Conductive Epoxy
* Die Attach:
Conductive Epoxy
Note. Connect exposed pad (heat sink on the back) to GND.
2
Rev. A.01
AME
AME5287
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
n Pin Description
Pin No.
Pin Name
Pin Description
1
COMP
Compensation Node. COMP is used to compensate the regulation control loop.
Connect a series RC network from COMP to GND to compensate the regulation
control loop. In some cases, an additional capacitor from COMP to GND is
required.
2
GND
3
EN
Enable. Pull EN below 0.4V to shut down the regulator.
4
IN
Power Input. IN supplies the power to the IC, as well as the step-down converter
switches. Bypass IN to GND with a suitable large capacitor to eliminate noise on
the input to the IC.
5, 6
SW
7
FREQ
8
FB
9
GND
Rev. A.01
Ground. Connect the exposed pad to GND.
Power Switching Output. SW is the switching node that supplies power to the
output. Connect the output LC filter from SW to the output load.
Frequency Adjust Pin. Add a resistor from this pin to ground determines the
switching frequency.
Feedback Input. FB senses the output voltage to regulate that voltage. Drive FB
with a resistive voltage divider from the output voltage. The feedback reference
voltage is 0.8V.
Ground. Connect the exposed pad to GND.
3
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Ordering Information
AME5287 - x x x xxx
Output Voltage
Number of Pins
Package Type
Pin Configuration
Pin Configuration
A
(SOP-8/PP)
(DFN-8C)
4
1. COMP
2. GND
3. EN
4. IN
5. SW
6. SW
7. FREQ
8. FB
9. GND
Package Type
Z: SOP/PP
V: DFN
Number of Pins
A: 8
Output Voltage
ADJ: Adjustable
Rev. A.01
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Absolute Maximum Ratings
Parameter
Symbol
Maximum
Unit
Supply Voltage
VIN
6
V
Switch Voltage
VSW
-1.5V to VIN +0.7V
V
-0.3V to VIN +0.3V
V
HBM
2
kV
MM
200
V
EN, FB, COMP, FREQ to GND
ESD Classification
n Recommended Operating Conditions
Parameter
Symbol
Rating
Ambient Temperature Range
TA
-40 to +85
Junction Temperature Range
TJ
-40 to +125
Storage Temperature Range
TSTG
-65 to +150
Unit
o
C
n Thermal Information
Parameter
Package
Thermal Resistance*
(Junction to Case)
SOP-8/PP
Thermal Resistance
(Junction to Ambient)
SOP-8/PP
Internal Power Dissipation
Die Attach
θ JC
DFN-8C
DFN-8C
SOP-8/PP
DFN-8C
Symbol Maximum
Conductive Epoxy
θJA
PD
Unit
15
8.2
75
o
C/W
70
1.333
W
1.429
Maximum Junction Temperature
150
o
C
Lead Temperature (soldering 10 sec)**
260
o
C
* Measure θJC on backside center of Exposed Pad.
** MIL-STD-202G 210F
Rev. A.01
5
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Electrical Specifications
VIN=5V, TA=25oC, unless otherwise noted.
Parameter
Input Voltage
Input UVLO
Symbol
Test Condition
VIN
Min
Typ
3
VUVLO
Quiescent Current
IQ
VEN=5V, VFB=0.7V
(No Switching)
Shutdown Current
ISHDN
VEN=0V
Feedback Voltage
VFB
0.784
Feedback Current
IFB
-50
Units
5.5
V
2.3
V
600
µA
0.8
1
µA
0.816
V
50
nA
Load Regulation
REGLOAD
0A<I OUT <2A
0.25
%
Line Regulation
REG LINE
2.7V<VIN<5.5V
0.25
%/V
EN Voltage High
1.4
VEN
V
EN Voltage Low
EN Leakage Current
Switching Frequency
IENLK
FSW
VEN=3V
Error Amp Transconductance
GEA
Switch Leakage Current
ISWLK
0.4
V
0.1
1
µA
R FREQ=NC
240
300
360
KHz
R FREQ=120K Ω
480
600
720
KHz
RFREQ=47K Ω
0.8
1
1.2
MHz
RFREQ=18KΩ
1.6
2
MHz
3.7
A
400
µA/V
High-side Switch Current Limit
VSW=0V, V EN =0V
0.1
20
µA
High-side Switch On Resistance
RDSON,HI
130
mΩ
Low-side Switch On Resistance
R DSON,LO
90
mΩ
Thermal Shutdown Protection
6
Max
OTP
Rising
160
o
C
OTH
Hysteresis
20
o
C
Rev. A.01
AME
AME5287
n Detailed Description
Normal Operation
The AME5287 uses a user adjustable frequency, current mode step-down architecture with internal MOSFET
switch. During normal operation, the internal high-side
(PMOS) switch is turned on each cycle when the oscillator sets the SR latch, and turned off when the comparator resets the SR latch. The peak inductor current at
which comparator resets the SR latch is controlled by
the output of error amplifier EA. While the high-side switch
is off, the low-side switch turns on until either the inductor current starts to reverse or the beginning of the next
switching cycle.
Dropout Operation
The output voltage is dropped from the input supply for
the voltage which across the high-side switch. 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 high-side switch to remain on for more
than one cycle until it reaches 100% duty cycle.
Soft-Start
The AME5287 has a built-in digital soft-start to control
the output voltage rise and limit the current surge at the
start-up.
When the internal soft-start begins, and count 896
switching cycles, soft start is complete, the converter
enters steady state operation.
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
Under Voltage Protection
Under Voltage Protection will activate once the feedback voltage falls below 0.4V, the operating frequency is
switched to 1/10 of normal switching frequency and after
four-times hiccup mode counted, the internal high-side
power switch will be turned off,and latched. Unless Restart the power supply.
Over Temperature Protection
In most applications the AME5287 does not dissipate
much heat due to high efficiency. But, in applications
where the AME5287 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, the internal
high-side power switch will be turned off and the SW
switch will become high impedance.
Inductor Selection
For most applications, the value of the inductor will fall
in the range of 2.2µH to 4.7µH. Its value is chosen based
on the desired ripple current. Large value inductors lower
ripple current and small value inductors result in higher
ripple currents. Higher V IN or V OUT also increase the ripple
current ∆IL:
∆I L =
 V
1
VOU T 1 − OUT
f ×L
VIN




Hiccup Mode
During hiccup mode, the AME5287 disables the highside MOSFET and begins a cool down period of 8320
switching cycles. At the conclusion of this cool down
period, the regulator performs an internal 896 cycle soft
start identical to the soft start at turn-on.
Rev. A.01
7
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
A reasonable inductor current ripple is usually set as 1/
3 to 1/5 of maximum out current. The DC current rating
of the inductor should be at least equal to the maximum
load current plus half the ripple current to prevent core
saturation. For better efficiency, choose a low DCR inductor.
Output Voltage Programming
The output voltage of the AME5287 is set by a resistive
divider according to the following formula:
 R1 
VOUT = 0.8 × 1 +
Volt .
 R2
Capacitor Selection
In continuous mode, the source current of the top
MOSFET is a square wave of duty cycle VOUT/VIN. To
prevent large voltage transients, a low ESR input capacitor sized for maximum RMS current must be used. The
maximum RMS capacitor current is given by:
CIN requires IRMS
≅ I OMAX
VOUT (VIN − VOUT )
VIN
This formula has a maximum at V IN =2V OUT ,
whereIRMS=IOUT/2. For simplification, use an input capacitor with a RMS current rating greater than half of the
maximum load current.
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:
∆VOUT

1
≅ ∆I L  ESR +
8 fCOUT

Loop Compensation
The AME5287 employs peak current mode control for
easy use and fast transient response. Peak current mode
control eliminates the double pole effect of the output LC
filter. It greatly simplifies the compensation loop design.
With peak current mode control, the buck power
stagecan be simplified to be a one-pole and one-zero system in frequency domain. The pole can be calculated by:
f P1 =
1
2π × COUT × RL
The zero is a ESR zero due to output capacitor and its
ESR. It can be calculated by:
f Z1 =
1
2π × COUT × ESRCOUT



For a fixed output voltage, the output ripple is highestat
maximum input voltage since ∆IL increases with input voltage.
When choosing the input and output ceramic capacitors, choose the X5R or X7R dielectric formulations. These
dielectrics have the best temperature and voltage characteristics of all the ceramics for given value and size.
8
Rev. A.01
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
Where COUT is the output capacitor, RL is load resistance; ESRCOUT is the equivalent series resistance of
output capacitor.
The compensation design is to shape the converter close
loop transfer function to get desired gain and phase. For
most cases, a series capacitor and resistor network connected to the COMP pin sets the pole-zero and is adequate for a stable high-bandwidth control loop.
In the AME5287, FB pin and COMP pin are the inverting input and the output of internal transconductance error amplifier (EA). A series R3 and C1 compensation network connected to COMP pin provides one pole and one
zero: for R3<<AEA/GEA,
fP2 =
fZ2 =
1

A 
2π × C1  R3 + EA 
GEA 

≈
G EA
2π × C1 × AEA
1
2π × C1 × R3
where GEA is the error amplifier transconductance
AEA is the error amplifier voltage gain
R3 is the compensation resistor
C1 is the compensation capacitor
The desired crossover frequency fc of the system is
defined to be the frequency where the control loop has
unity gain. It is also called the bandwidth of the converter. In general, a higher bandwidth means faster response to load transient. However, the bandwidth should
not be too high because of system stability concern. When
designing the compensation loop, converter stability under all line and load condition must be considered. Usually, it is recommended to set the bandwidth to be less
than 1/10 of switching frequency. Using selected crossover frequency, fC, to calculate R3:
V
2π × COUT
R3 = f C × OUT ×
VFB G EA × GCS
Rev. A.01
Where GCS is the current sense circuit transconductance.
The compensation capacitor C1 and resistor R3 together
make zero. This zero is put somewhere close to the pole
fP1 of selected frequency. C1 is selected by:
C1 =
COUT × RL
R3
Checking Transient Response
The regulator loop response can be checked by looking at the load transient response. Switching regulators
take several cycles to respond to a step in load current.
When a load step occurs, VOUT immediately shifts by an
amount equal to (∆ILOAD X ESR), where ESR is the effective series resistance of COUT. ∆ILOAD also begins to charge
or discharge COUT, which generates a feedback error signal.
The regulator loop then acts to return VOUT to its
steadystate value. During this recovery time V OUT can be
monitored for overshoot or ringing that would indicate a
stability problem.
Efficiency Considerations
Although all dissipative elements in the circuit produce
losses, one major source usually account for most of the
losses in AME5287 circuits: I2R losses. The I2R loss
dominates the efficiency loss at medium to high load currents.
The I2R losses are calculated from the resistances of
the internal switches, RSW, and external inductor RL. In
continuous mode, the average output current flowing
through inductor L is "chopped" between the main switch
and the synchronous switch. Thus the series resistance
looking into the SW pin is a function of both top and bottom MOSFET RDS(ON) and the duty cycle (D) as follows:
RSW = (RDS(ON)TOP)(D) + (RDS(ON)BOTTOM )(1-D)
The RDS(ON) for both the top and bottom MOSFETs can
be obtained from Electrical Characteristics table. Thus,
to obtained I2R losses, simply add RSW to RL and multiply
the result by the square of the average output current.
9
AME
AME5287
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
Other losses including CIN and COUT ESR dissipative
losses and inductor core losses generally account for
less than 2% total additional loss.
Thermal Considerations
In most application the AME5287 does not dissipate
much heat due to its high efficiency. But, in applications
where the AME5287 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 switch will become high impedance.
10
Rev. A.01
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Typical Operating Circuit
VIN
2.5V to 5V
CIN
10µF
L
4
3
Chip Enable
1
C2
Optional
SW
IN
V OUT
5, 6
EN
R1
AME5287
COMP
FB
C1
FREQ
8
7
R3
2
RFREQ
GND
GND
COUT
R2
9 (Exposed pad)
VOUT(V)
C IN (µF)
R1(KΩ)
R2(K Ω)
R3(K Ω)
C1(pF )
L( µH)
COUT(µF )
3.3
10
75
24
25
680
2.2
22
2.5
10
51
24
20
680
2.2
22
1.8
10
30
24
15
680
1.5
22
1.5
10
21
24
13
680
1.5
22
1.2
10
12
24
11
680
1.5
22
1
10
6
24
8.2
680
1.5
22
Table 1. Recommended Components Selectin for fsw = 2MHz
The ground area must provide adequate heat
dissipating area to the thermal pad andusing
multiple vias to help thermal dissipation.
R3
Connect the
FB pin directly
to feedback
R2 resistors.
C1
COMP 1
8
FB
R1
GND
2
V OUT
GND
7 FREQ
RFREQ
GND
EN
3
6
SW
V IN
4
5
SW
SW
VI N
SW pad should be
connected together to
Inductor by wide and short
trace, keep sensitive
components away from
this trace .
L1
C IN must be placed
between VI N and
GND as close as
CIN
possible
Place the input and output
capacitors as close to the
IC as possible
C OUT
V OUT
Figure 3. AME5287 Regulators Layout Diagram
Rev. A.01
11
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Characterization Curve
Efficiency vs. Output Current
Efficiency vs. Output Current
100
100
90
90
80
70
VOUT=3.3V
V OUT =2.5V
VOUT=1.8V
Efficiency (%)
Efficiency (%)
80
VOUT=1.2V
60
V OUT =1.0V
50
40
30
60
V OUT =1.2V
50
V OUT=1.0V
40
20
V IN = 5V
R FREQ = 18K
10
0
500
1000
1500
2000
2500
V IN = 5V
R FREQ = 30K
10
0
3000
0
500
Output Current (mA)
100
100
90
90
2000
2500
3000
80
V OUT=3.3V
70
VOUT=2.5V
V OUT =1.8V
60
Efficiency (%)
Efficiency (%)
1500
Efficiency vs. Output Current
80
V OUT=1.2V
VOUT=1.0V
50
40
30
70
V OUT=3.3V
VOUT=2.5V
VOUT=1.8V
60
V OUT=1.2V
50
VOUT=1.0V
40
30
20
V IN = 5V
R FREQ = 47K
10
0
500
1000
1500
2000
Output Current (mA)
12
1000
Output Current (mA)
Efficiency vs. Output Current
0
VOUT=2.5V
VOUT=1.8V
30
20
0
VOUT=3.3V
70
2500
3000
20
VIN = 5V
R FREQ = NC
10
0
0
500
1000
1500
2000
2500
3000
Output Current (mA)
Rev. A.01
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Characterization Curve (Contd.)
Load Step
Load Step
VIN = 3.3V
VOUT= 1.8V
IOUT= 1A to 3A
VIN= 3.3V
VOUT= 1.0V
IOUT= 1A to 3A
1
1
2
2
Time (200µSec/DIV)
Time (200µSec/DIV)
1) VOUT= 200mV/div
2) IL= 2A/div
1) VOUT= 200mV/div
2) IL= 2A/div
Load Step
Load Step
VIN= 5.0V
VOUT= 1.0V
IOUT= 1A to 3A
VIN = 5.0V
VOUT = 3.3V
I OUT = 1A to 3A
1
1
2
2
Time (200µSec/DIV)
1) VOUT= 200mV/div
2) IL= 2A/div
Rev. A.01
Time (200µSec/DIV)
1) VOUT= 200mV/div
2) IL= 2A/div
13
AME
AME5287
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
n Characterization Curve (Contd.)
Power ON from VIN
1
Power off from VIN
1
2
2
3
3
4
4
2.0mS / div
2.0mS / div
1) VIN= 5V/div
2) Vsw= 5V/div
3) VOUT= 1V/div
4) IL= 2A/div
1) VIN= 5V/div
2) Vsw= 5V/div
3) VOUT= 1V/div
4) IL= 5A/div
Start-Up from EN
Power Off from EN
1
1
2
2
3
3
4
4
2.0mS / div
1) EN= 5V/div
2) VSW= 5V/div
3) VOUT= 1V/div
4) IL = 2A/div
14
1.0mS / div
1) EN= 5V/div
2) VSW= 5V/div
3) VOUT= 1V/div
4) IL = 5A/div
Rev. A.01
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Characterization Curve (Contd.)
Steady State Test
Steady State Test
VIN = 5V
VOUT= 3.3V
IOUT= 3A
VIN = 5V
VOUT= 1.1V
IOUT= 3A
1
1
2
2
400nS / DIV
400nS / DIV
1) VOUT= 10mV/div
2) VSW= 2V/div
1) VOUT= 10mV/div
2) VSW= 2V/div
VFB vs. Temperature
Frequency vs. Temperature
450
0.82
400
Frequency (KHz)
VFB (V)
0.81
0.80
0.79
0.78
0.77
-40
V IN = 5V
-25
-10
+5
+20
+35 +50 +65 +80
Temperature (°C)
Rev. A.01
+95 +110 +125
350
300
250
VIN = 5V
200
150
-40
-25
-10
+5
+20
+35 +50
+65 +80
+95 +110 +125
Temperature ( °C)
15
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
„ Characterization Curve (Contd.)
Frequency vs. Output Current
Frequency vs. Supply Voltage
450
300
290
400
Frequency (KHz)
Frequency (KHz)
280
350
300
250
VOUT = 3.3V
200
270
260
250
240
230
VIN=5.0V
VOUT = 3.3V
220
210
150
3.5
4
4.5
5
5.5
Input Voltage (V)
200
200
400
600
800
1000
1200
1400
1600 1800 2000
Iout (mA)
Short Circuit Test
Short Circuit Test
VIN =5V
VOUT=1V
VIN=5V
VOUT=3.3V
1
1
2
2
Time (100ms/DIV)
1) VOUT= 1V/div
2) IOUT= 2A/div
16
Time (100ms/DIV)
1) VOUT= 2V/div
2) IOUT= 2A/div
Rev. A.01
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Tape and Reel Dimension
SOP-8/PP
P
PIN 1
W
AME
AME
Carrier Tape, Number of Components Per Reel and Reel Size
Package
Carrier Width (W)
Pitch (P)
Part Per Full Reel
Reel Size
SOP-8/PP
12.0±0.1 mm
4.0±0.1 mm
2500pcs
330±1 mm
DFN-8C
(3mmx3mmx0.75mm)
P
PIN 1
W
AME
AME
Carrier Tape, Number of Components Per Reel and Reel Size
Package
Carrier Width (W)
Pitch (P)
Part Per Full Reel
Reel Size
DFN-8C
(3x3x0.75mm)
12.0±0.1 mm
4.0±0.1 mm
3000pcs
330±1 mm
Rev. A.01
17
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Package Dimension
SOP-8/PP
TOP VIEW
SIDE VIEW
D1
SYMBOLS
?
E1
E2
E
L1
C
PIN 1
D
e
A1
FRONT VIEW
18
A
A2
b
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
1.270 BSC
e
0.050 BSC
θ
0
8
E2
2.150
2.513
0.085
0.099
D1
2.150
3.402
0.085
0.134
o
o
0
o
8
o
Rev. A.01
AME
3A, 300KHz ~ 2MHz Synchronous
Rectified Step-Down Converter
AME5287
n Package Dimension (Contd.)
DFN-8C
(3mmx3mmx0.75mm)
b
D
e
L
E
E1
PIN 1 IDENTIFICATION
TOP VIEW
D1
BOTTOM VIEW
A
G1
G
REAR VIEW
SYMBOLS
Rev. A.01
MILLIMETERS
INCHES
MIN
MAX
MIN
MAX
A
0.700
0.800
0.028
0.031
D
2.900
3.100
0.114
0.122
E
2.900
3.100
0.114
0.122
e
0.600
0.700
0.024
0.028
D1
2.200
2.400
0.087
0.094
E1
1.400
1.600
0.055
0.063
b
0.180
0.320
0.007
0.013
L
0.375
0.575
0.015
0.023
G
0.153
0.253
0.006
0.010
G1
0.000
0.050
0.000
0.002
19
www.ame.com.tw
E-Mail: sales@ame.com.tw
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. , October 2012
Document: TU003-DS5287-A.01
Corporate Headquarter
AME, Inc.
8F, 12, WenHu St., Nei-Hu
Taipei 114, Taiwan .
Tel: 886 2 2627-8687
Fax: 886 2 2659-2989