AME
AME5145
n
General Description
The AME5145 switching regulator is current-mode boost
converters operating at fixed frequency of 1.6 MHz.
The use of SOT-25/TSOT-25, DFN-8C & MSOP-8 pack-
ages, made possible by the minimal power loss of the
internal 1.8A switch, and use of small inductor and ca-
pacitors result in the industry's highest power density.
The 30V internal switch makes these solutions perfect
for boosting to voltages up to 30V.
These parts have a logic-level shutdown pin that can
be used to reduce quiescent current and extend battery
life. Protection is provided through cycle-by-cycle cur-
rent limiting and thermal shutdown. Internal compensa-
tion simplifies and reduces component count.
1.6 MHz Boost Converter With
30V Internal FET Switch
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Typical Application
L/6.8µH
V
IN
IN
4.2V
EN
R3
51K
EN
GND
C1
4.7µF
GND
R2
13.3K
CF
680pF
C2
22µF
SW
D1
V
OUT
5V
800mA
R1
43K
AME5145
FB
Figure 1. 4.2V to 5V Boost Converter
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Features
l
30V DMOS FET Switch
l
1.6 MHz Switching Frequency
l
Low R
DSON
DMOS FET
l
Switch Current Up to 1.8A
l
Wide Input Voltage Range (2.7V-5.5V)
l
Low Shutdown Current (<1µA)
l
SOT-25/TSOT-25, DFN-8C & MSOP-8 Packages
l
Uses Tiny Capacitors and Inductor
l
Cycle-by-Cycle Current Limiting
l
All AME's Lead Free Products Meet RoHS
Standards
GND
C1
4.7µF
V
IN
IN
5V
EN
R3
51K
EN
L/10µH
D1
SW
V
OUT
12V
400mA
FB
GND
CF
220pF
C2
4.7µF
R1
117K
AME5145
R2
13.3K
Figure 2. 5V to 12V Boost Converter
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Applications
l
White LED Current Source
l
PDA's and Palm-Top Computers
l
Digital Cameras
l
Portable Phones and Games
l
Local Boost Regulator
C1
4.7µF
GND
EN
V
IN
IN
5V
R3
51K
EN
L/10µH
D1
SW
V
OUT
18V
250mA
R1
183K
AME5145
FB
GND
R2
13.3K
CF
160pF
C2
4.7µF
Figure 3. 5V to 18V Boost Converter
Rev.B.01
1
AME
AME5145
n
Function Block Diagram
EN
SW
1.6 MHz Boost Converter with
30V Internal FET Switch
VIN
SHUTDOWN
CIRCUITRY
R5
R6
THERMAL
SHUTDOWN
+
Q1
FB
R
C
R3
Q2X8
R
Gm
RAMP
GENERATOR
-
+
Σ
-
R
R
S
Q
DRIVER
oscillator
C
C
CURRENT
LIMIT
COMP
+
R4
-
GND
Figure 4. Functional Block Diagram
2
Rev.B.01
AME
AME5145
n
Pin Configuration
SOT-25/TSOT-25
Top View
5
4
1.6 MHz Boost Converter With
30V Internal FET Switch
MSOP-8
Top View
AME5145AEEV
1. SW
2. GND
8
7
6
5
AME5145AEQA
1. IN
2. EN
3. GND
AME5145
3. FB
4. EN
5. IN
AME5145
4. FB
5. SW
6. SW
7. GND
8. GND
1
2
3
1
2
3
4
*
Die Attach:
Conductive Epoxy
*
Die Attach:
Conductive Epoxy
DFN-8C
(3mmx3mmx0.75mm)
Top View
AME5145AEVA
8
7
6
5
1. NC
2. FB
3. NC
4. SW
5. NC
6. IN
AME5145
1
2
3
4
7. EN
8. NC
*
Die Attach:
Conductive Epoxy
Note: The trapezoid area enclosed by dashed line represents Exposed Pad and is GND.
Rev.B.01
3
AME
AME5145
n
Pin Description (Continued)
AME5145AEEV SOT-25/TSOT-25
Pin Number
1
2
Pin Name
SW
GND
Pin Description
Power Switch input.
This is the drain of the internal NMOS power switch.
Minimize the metal trace area connected to this pin to minimize EMI.
Ground. Tie directly to ground plane.
Output voltage feedback input.
Set the output voltage by selecting values for R1 and R2 using:
3
FB
1.6 MHz Boost Converter with
30V Internal FET Switch
V
R
1
=
R
2
out
−
1
1 . 23
V
Connect the ground of the feedback network to a GND plane.
Enable, active high.
The enable pin is an active high control. Tie this pin above 2V to enable the
device. Tie this pin below 0.4V to turn off the device.
Analog and Power input. Input Supply Pin.
Place bypass capacitor as close to V
IN
as possible.
4
EN
5
IN
AME5145AEQA MSOP-8
Pin Number
1
Pin Name
IN
Pin Description
Analog and Power input. Input Supply Pin.
Place bypass capacitor as close to V
IN
as possible.
Enable, active high.
The enable pin is an active high control. Tie this pin above 2V to enable the
device. Tie this pin below 0.4V to turn off the device.
Ground. Tie directly to ground plane.
Output voltage feedback input.
Set the output voltage by selecting values for R1 and R2 using:
4
FB
2
3
EN
GND
5
SW
6
7
8
4
SW
GND
GND
Connect the ground of the feedback network to a GND plane.
Power Switch input.
This is the drain of the internal NMOS power switch.
Minimize the metal trace area connected to this pin to minimize EMI.
Power Switch input.
This is the drain of the internal NMOS power switch.
Minimize the metal trace area connected to this pin to minimize EMI.
Ground. Tie directly to ground plane.
Ground. Tie directly to ground plane.
Rev.B.01
V
R
1
=
R
2
out
−
1
1 . 23
V
AME
AME5145
n
Pin Description
AME5145AEVA DFN-8C(3mmx3mmx0.75mm)
Pin Number
1
Pin Name
NC
Not Connected
1.6 MHz Boost Converter With
30V Internal FET Switch
Pin Description
Output voltage feedback input.
Set the output voltage by selecting values for R1 and R2 using:
2
FB
V
R
1
=
R
2
out
−
1
1 . 23
V
Connect the ground of the feedback network to a GND plane.
Not Connected
Power Switch input.
This is the drain of the internal NMOS power switch.
Minimize the metal trace area connected to this pin to minimize EMI.
Not Connected
Analog and Power input. Input Supply Pin.
Place bypass capacitor as close to V
IN
as possible.
Enable, active high.
The enable pin is an active high control. Tie this pin above 2V to enable the
device. Tie this pin below 0.4V to turn off the device.
Not Connected
3
4
5
6
NC
SW
NC
IN
7
8
EN
NC
Rev.B.01
5
RF/Wirelessly
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