ETC AS1318

AS1308A
1.2MHz, 2.0A Sync. Buck Converter
FEATURES
GENERAL DESCRIPTION
High Efficiency:Up to 95%
The AS1308A is a 1.2MHz constant frequency
1.2MHz Constant Switching Frequency
current mode PWM step-down converter. It is ideal
2.0A available Load Current
for portable equipment requiring very high current up
2.5V to 6.0V Input Voltage Range:
to 2A from single-cell lithium batteries while still
Output Voltage as low as 0.6V
achieving over 90% efficiency during peak load
100% Duty Cycle In Dropout
conditions. The AS1308A also can run at 100% duty
Low RDS(ON) Internal Switch:0.15Ω
cycle for low dropout operation, extending battery life
Current Mode Control for Excellent Line & Load
in portable systems while light load operation
Regulation
provides very low output ripple for noise sensitive
Short Circuit and Thermal Fault Protection
applications. The AS1308A can supply up to 2A
Soft Start & Shutdown Current <1μA
output load current from a 2.5V to 6.0V input voltage
Space Saving Package:TDFN33-10L,
and the output voltage can be regulated as low as
MSOP-10L
0.6V. The high switching frequency minimizes the
size of external components while keeping switching
losses low. The internal slope compensation setting
APPLICATIONS
allows the device to operate with smaller inductor
Cellular & Smart Phones
values to optimize size and provide efficient
Microprocessors and DSP Core Supplies
operation. The AS1308A is available in adjustable
Wireless and DSL Modems
and fixed output voltage.
PDAs & Portable Equipments
The device is available in a TDFN-10L(3x3mm) &
MSOP-10L package and is rated over the -40°C to
85°C temperature range.
TYPICAL APPLICATION
INPUT
2.5V – 5.5V
2
IN
3
IN
C1
22uF
OFF ON
AS1308A
8
LX
7
LX
OUT/FB
1 EN
6 GND
4 GND
PGND
PGND
L1
2.2uH
C3
22pF
5
10
9
R2
316 K
1%
R1
634K
1%
OUTPUT
1.8V/2A
C2
22uF
High efficiency sync. step-down Converter
AS1308A Rev.1.0
10/25/2008
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
ABSOLUTE MAXIMUM RATINGS
PACKAGE/ORDER INFORMATION
(Note1)
TOP VIEW
VIN Voltage ………………………..….. -0.3V to 6V
VEN, VFB Voltage ………….…. -0.3V to VIN +0.3V
VLX, VOUT Voltage ………….…. -0.3V to VIN +0.3V
PGND,AGND Ground Voltage………-0.3V to 6V
Operating Temperature Range...… -40℃ to 85℃
PD Power Dissipation …………………..2.2W(Note2)
ΘJA Thermal Resistance…………………………...45°C/W
Storage Temperature Range …... -65℃ to 150℃
Lead Temperature(Soldering, 10sec.) ……300℃
Note 1: Absolute Maximum Ratings are those values beyond
which the life of a device may be impaired.
PART NUMBER
PACKAGE
OPERATING TEMP.
AS1308AEPT
TDFN-10L
-40°C to 85°C
AS1308AEFT
MSOP-10L
-40°C to 85°C
Note 2: TJ is calculated from the ambient temperature TA and
power dissipation PD according to the following
formula: TJ = TA + PD x ΘJA
ELECTRICAL CHARACTERISTICS
VIN = VEN =3.6V, TA = 25°C Unless otherwise noted.
PARAMETER
CONDITIONS
MIN
TYP
MAX
Input Voltage Range
2.5
-
6.0
Output Voltage Range
0.6
-
VIN
PWM Mode, VFB = 0.5V or VOUT=90%
-
300
500
Power Saving Mode, VFB = 0.63V
-
40
80
Shutdown Mode, VFB = 0V, VAIN = 5.5V
-
0.1
1.0
TA = 25°C
0.5880
0.6000
0.6120
TA = 0°C ≤ TA ≤ 85°C
0.5865
0.6000
0.6135
TA = -40°C ≤ TA ≤ 85°C
0.5850
0.6000
0.6150
Input Supply Current
Regulated Feedback
Voltage
UNITS
V
μA
V
FB Input Bias Current
VFB = 0.65V
-
-
±30
nA
Line Regulation
VIN = 2.5V to 5.5V, IOUT = 10mA
-
0.1
0.2
%/V
Load Regulation
IOUT = 10mA to 2.0A
-
0.2
-
%/A
2.5
3.5
-
A
0.96
1.2
1.44
MHz
VIN=3V, VFB= 0.5V or VOUT = 90%;
Peak Inductor Current
Duty Cycle <35%
Oscillator Frequency
VFB = 0.6V or VOUT = 100%
P-CH MOSFET RDS(ON)
VIN = 3.6V
-
0.135
0.20
N-CH MOSFET RDS(ON)
VIN=3.6V
-
0.095
0.15
LX Leakage
VEN=0V, VLX=0V or 5V, VIN=5V
±0.01
±1
uA
Enable Threshold
TA = -40°C ≤ TA ≤ 85°C
1.0
1.5
V
Enable Leakage Current
VIN=VEN=5.5V
±0.01
±1
μA
0.3
Ω
Note: 100% production test at +25℃; Specification over the temperature range are guaranteed by design.
AS1308A Rev.1.0
10/25/2008
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
TYPICAL PERFORMANCE CHARACTERISTICS
L=2.2uH, Cin=Cout=22uF; TA = 25°C; Unless otherwise noted.
100
QUIESCENT CURRENT vs
SUPPLY VOLTAGE
1.6 1.4 EN THRESHOLD VOLTAGE (V)
90
QUIESCENT CURRENT (uA)
EN THRESHOLD VOLTAGE vs
SUPPLY VOLTAGE
80
70
60
50
40
30
1.2 1.0 0.8 0.6 0.4 20
0.2 10
0.0 2.0 0
2.0 3.0 4.0 5.0 6.0 3.0 4.0 5.0 6.0 5.0 6.0 SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
1.3
FREQUENCY vs.
SUPPLY VOLTAGE
FREQUENCY (MHz)
1.28
1.26
1.24
1.22
1.2
1.18
1.16
2.0 3.0 4.0 SUPPLY VOLTAGE (V)
AS1308A Rev.1.0
10/25/2008
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
TYPICAL PERFORMANCE CHARACTERISTICS
L=2.2uH, Cin=Cout=22uF; TA = 25°C; Unless otherwise noted.
OUTPUT VOLTAGE (V)
1.9
OUTPUT VOLTAGE vs.
SUPPLY VOLTAGE
1.85
Vout=1.8V
Iout=1.0A
1.8
1.75
1.7
2.0 3.0 4.0 5.0 6.0 SUPPLY VOLTAGE (V)
Vin=4.2V, Vout=1.8V, Iout=800mA
AS1308A Rev.1.0
10/25/2008
Vin=3.3V, Vout=1.8V, Iout=800mA
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
PIN FUNCTIONS
PIN NUMBER
PIN NAME
FUNCTION
Enable control input. Forcing this pin above 1.5V enables the part. Forcing
1
this pin below 0.3V shuts down the device. In shutdown, all functions are
EN
disabled drawing <1μA supply current. Do not leave EN floating.
Power supply input pin. Must be closely decoupled to AGND with a 2.2uF or
2,3
IN
4,6
GND
greater ceramic capacitor
Analog ground pin.
FB pin: adjustable version feedback input. Connect FB to the center point of
5
FB/OUT
the external resistor divider. The feedback threshold voltage is 0.6V. OUT
pin: Fixed version feedback input. Connect OUT to the output volgage, VOUT
7,8
LX
Switching node pin. Connect the output inductor to this pin.
9,10
PGND
Power ground pin.
Power ground exposed pad. Must be connected to bare copper ground
EP
plane.
BLOCK DIAGRAM
AS1308A Rev.1.0
10/25/2008
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
OPERATION
The AS1308A is a high output current monolithic
switch - mode step-down converter. The device
operates at a fixed 1.2MHz switching frequency, and
uses a slope compensated current can supply up to
2A output current at Vin=3V and has an input voltage
range from 2.5V to 6.0V. it minimizes external
component size and optimizes efficiency at the
heavy load range. The slope compensation allows
the devices to remain stable over a wider range of
inductor values so that smaller values(1uH to 4.7uH)
with lower DCR can be used to achieve higher
efficiency. Apart from the small bypass input
capacitor, only a small L-C filter is required at the
output. The fixed output version requires only three
external power components (Cin, Cout, and L). the
adjustable version can be programmed with external
feedback to any voltage, ranging from 0.6V to near
the input voltage. It uses internal MOSFETs to
achieve high efficiency and can generate very low
output voltages by using an internal reference of
0.6V. at dropout, the converter duty cycle increases
to 100% and the output voltage tracks the input
voltage minus the low RDS(ON) drop of the P-channel
high-side MOSFET and the inductor DCR. The
internal error amplifier and compensation provides
excellent transient response, load and line regulation.
Internal soft start eliminates any output voltage
overshoot when the enable or the input voltage is
applied.
CURRENT MODE PWM CONTROL
Slope compensated current mode PWM control
provides stable switching and cycle-by-cycle current
limit for excellent load and line response and
protection of the internal main switch and
synchronous rectifier. The AS1308A switches at a
constant frequency (1.2MHz) and regulates the
output voltage. During each cycle the PWM
comparator modulates the power transferred to the
load by changing the inductor peak current based on
the feedback error voltage. During normal operation,
the main switch is turned on for a certain time to
ramp the inductor current at each rising edge of the
internal oscillator, and switched off when the peak
inductor current is above the error voltage. When the
main switch is off, the synchronous rectifier will be
turned on immediately and stay on until either the
next cycle starts.
CONTROL LOOP
The AS1308A is a peak current mode step-down
AS1308A Rev.1.0
10/25/2008
converter. The current through the P-channel
MOSFET(high side) is sensed for current loop
control, as well as short circuit and overload
protection. A slop compensation signal is added to
the sensed current to maintain stability for duty
cycles greater than 50%. The peak current mode
loop appears as a voltage-programmed current
source in parallel with the output capacitor. The
output of the voltage error amplifier programs the
current mode loop for the necessary peak switch
current to force a constant output voltage for all load
and line conditions. Internal loop compensation
terminates the transconductance voltage error
amplifier output. For fixed voltage versions, the error
amplifier reference voltage is internally set to
program the converter output voltage. For the
adjustable output, the error amplifier reference is
fixed at 0.6V.
SOFT START/ENABLE
Soft start limits the current surge seen at the input
and eliminates output voltage overshoot. The enable
pin is active high. When pulled low, the enable
input(EN) forces the AS1308A into a low-power,
non-switching state. The total input current during
shutdown is less than 1uA.
CURRENT LIMIT and OVER-TEMPERATURE
PROTECTION
For overload conditions, the peak input current is
limited to 3.5A. To minimize power dissipation and
stresses under current limit and short-circuit
conditions, switching is terminated after entering
current limit for a series of pulses. The termination
lasts for seven consecutive clock cycles after a
current limit has been sensed during a series of four
consecutive clock cycles. Thermal protection
completely disables switching when internal
dissipation becomes excessive the junction over
temperature threshold is 170°C with 10°C of
hysteresis. Once an over temperature or over
current fault conditions is removed, the output
voltage automatically recovers.
DROPOUT OPERATION
When the battery input voltage decreases near the
value of the output voltage, the AS1308A allows the
main switch to remain on for more than one
switching cycle and increases the duty cycle until it
reaches 100%. The duty cycle D of a step-down
converter is defined as:
D
Ton Fosc 100%
Vout
Vin
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
Where Ton is the main switch on time and Fosc is
the oscillator frequency. The output voltage then is
the input voltage minus the voltage drop across the
main switch and the inductor. At low input supply
voltage, the RDS(ON) of the P-channel MOSFET
increases, and the efficiency of the converter
decreases. Caution must be exercised to ensure the
heat dissipated does not exceed the maximum
junction temperature of the IC.
MAXIMUM LOAD CURRENT
The AS1308A will operate with an input supply
voltage as low as 2.5V, however, the maximum load
current decreases at lower input voltages due to a
large IR drop on the main switch and synchronous
rectifier. The slope compensation signal reduces the
peak inductor current as a function of the duty cycle
to prevent sub-harmonic oscillations at duty cycles
greater than 50%. Conversely the current limit
increases as the duty cycle decreases.
APPLICATION INFORMATION
Figure 1: Application circuit for the adjustable output version
Figure2: Application circuit for the fixed output version.
SETTING THE OUTPUT VOLTAGE
Figure 1 shows the basic application circuit with the
AS1308A adjustable output version while figure 2
shows the application circuit with the AS1308A fixed
output version. For applications requiring an
adjustable output voltage, the AS1308A-adj can be
externally programmed. Resistors R1 and R2 in
figure1 program the output to regulate at a voltage
higher than 0.6V. to limit the bias current required for
the external feedback resistor string while
AS1308A Rev.1.0
10/25/2008
maintaining good noise immunity, the minimum
suggested value for R2 is 59K. Although a larger
value will further reduce quiescent current, it will also
increase the impedance of the feedback node,
making it more sensitive to external noise and
interference. Table1 summarizes the resistor values
for various output voltages with R2 set to either 59K
for good noise immunity or 316K for reduced no load
input current. The adjustable version of the
AS1308A,
combined with an external feed forward capacitor(C3
in figure 1), delivers enhanced transient response for
extreme pulsed load applications. The addition of the
feed forward capacitor typically requires a larger
output capacitor C2 for stability. The external resistor
sets the output voltage according to the following
equation:
R1
Vout 0.6V 1
R2
Vout
1 R2
R1
0.6V
Table1 shows the resistor selection for different
output voltage settings.
Vout
R1
R2
1.2V
316K
316K
1.5V
470K
316K
1.8V
634K
316K
2.5V
1M
316K
Note: standard 1% resistors
INDUCTOR SELECTION
For most designs, the AS1308A operates with
inductor values of 1uH to 4.7uH. low inductance
values are physically smaller but require faster
switching, which results in some efficiency loss. The
inductor value can be derived from the following
equation:
Vout Vin Vout
L
Vin
IL fosc
Where △IL is inductor ripple current. Large value
inductors lower ripple current and small value
inductors result in high ripple currents. Choose
inductor ripple current approximately 30% of the
maximum load current 2A or △IL=600mA
For output voltages above 2.0V, when light load
efficiency is important, the minimum recommended
Inductor is 2.2uH. manufacturer’s specifications list
both the inductor DC current rating, which is a
thermal limitation, and the peak current rating, which
is determined by the saturation characteristics.
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
The inductor should not show any appreciable
saturation under normal load conditions. Some
inductors may meet the peak and average current
ratings yet result in excessive losses due to a high
DCR. Always consider the losses associated with
the DCR and its effect on the total converter
efficiency when selecting an inductor. For optimum
voltage-positioning load transients, choose an
inductor with DC series resistance in the 20mΩ to
100mΩ range. For higher efficiency at heavy
loads(above 200mA), or minimal load regulation (but
some transient overshoot), the resistance should be
kept below 100mΩ. 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 (2A+600mA). Table2 lists some
typical surface mount inductors that meet target
applications for the AS1308A. For example, the
2.2uH CDRH5D16-2R2 inductor selected from
sumida has a 28.7mΩ DCR and a 3.0A DC current
rating. At full load, the inductor DC loss is 57mW
which gives a 1.6% loss in efficiency for 1.8V/1.2A.
SLOP COMPENSATION
The AS1308A step-down converter uses peak
current mode control with slope compensation for
stability when duty cycles are greater than 50%. The
slope compensation is set to maintain stability with
lower value inductors which provide better overall
efficiency. The output inductor value must be
selected so the inductor current down slope meets
the internal slope compensation requirements. As an
example, the value of the slope compensation is set
to 1A/us which is large enough to guarantee stability
when using a 2.2uH inductor for all output voltage
levels from 0.6V to 3.3V. the worst case external
current slope(m) using the 2.2uH inductor is when
Vout=3.3V and is:
m
Vout
L
3.3
2.2
1.5A/us
to keep the power supply stable when the duty cycle
is above 50%, the internal slope compensation(m)
should be:
ma
1
m
2
0.75A/us
Therefore, to guarantee current loop stability, the
slope of the compensation ramp must be greater
than one-half of the down slop of the current
waveform. So the internal slope compensated value
AS1308A Rev.1.0
10/25/2008
of 1A/us will guarantee stability using a 2.2uH
inductor value for all output voltage from 0.6V to
3.3V.
INPUT CAPACITOR SELECTION
The input capacitor reduces the surge current drawn
from the input and switching noise from the device.
The input capacitor impedance at the switching
frequency should be less than the input source
impedance to prevent high frequency switching
current passing to the input. The calculated value
varies with input voltage and is a maximum when Vin
is double the output voltage.
Cin
Vo
Vin
Vpp
Io
Cin min
1
Vo
Vin
ESR
fs
1
Vpp
Io
ESR
4 fs
A low ESR input capacitor sized for maximum RMS
current must be used. Ceramic capacitors with X5R
or X7R dielectrics are highly recommended because
of their low ESR and small temperature coefficients.
A 22uF ceramic capacitor for most applications is
sufficient. A large value may be used for improved
input voltage filtering. The maximum input capacitor
RMS current is:
IRMS
IO
VO
1
VIN
VO
VIN
The input capacitor RMS ripple current varies with
the input and output voltage and will always be less
than or equal to half of the total DC load current.
IRMS MAX
1
I
2 O
To minimize stray inductance, the capacitor should
be placed as closely as possible to the IC. This
keeps the high frequency content of the input current
localized, minimizing EMI and input voltage ripple.
The proper placement of the input capacitor (C1) can
be seen in the evaluation board layout in Figure3
and 4. A laboratory test set up typically consists of
two long wires running from the bench power supply
to the evaluation board input voltage pins. The
inductance of these wires, along with the low ESR
ceramic input capacitor, can create a high Q network
that may affect converter performance.
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
This problem often become apparent in the form of
excessive ringing in the output voltage during load
transients. Errors in the loop phase and gain
measurements can also result. Since the inductance
of a short PCB trace feeding the input voltage is
significantly lower than the power leads from the
bench power supply, most applications do not exhibit
this problem. In applications where the input power
source lead inductance cannot be reduced to a level
that does not affect the converter performance, a
high ESR tantalum or aluminum electrolytic should
be placed in parallel with the low ESR, ESL bypass
ceramic. This dampens the high Q network and
stabilizes the system.
OUTPUT CAPACITOR SELECTION
The function of output capacitance is to store energy
to attempt to maintain a constant voltage. The
energy is stored in the capacitor’s electric field due to
the voltage applied. The value of output capacitance
is generally selected to limit output voltage ripple to
the level required by the specification. Since the
ripple current in the output inductor is usually
determined by L, VOUT and VIN, the series impedance
of the capacitor primarily determines the output
voltage ripple. The three elements of the capacitor
that contribute to its impedance (and output voltage
ripple) are equivalent series resistance (ESR),
equivalent series inductance (ESL), and capacitance
©, the output voltage droop due to a load transient is
dominated by the capacitance of the ceramic output
capacitor. During a step increase in load current, the
ceramic output capacitor alone supplies the load
current until the loop responds. Within three
switching cycles, the loop responds and the inductor
current increases to match the load current demand.
The relationship of the output voltage droop during
the switching cycles to the output capacitance can
be estimated by:
COUT
3
ILOAD
VDROOP fs
In many practical designs, to get the required ESR a
capacitor with much more capacitance than is
needed must be selected. For both continuous and
discontinuous inductor current mode operation, the
ESR of the COUT needed to limit the ripple to △Vo, V
peak to peak is:
ESR
VO
IL
AS1308A Rev.1.0
10/25/2008
Ripple current flowing through a capacitor’s ESR
Causes power dissipation in the capacitor. This
power dissipation causes a temperature increase
internal to the capacitor. Excessive temperature can
seriously shorten the expected life of a capacitor.
Capacitors have rippled current ratings that are
dependent on ambient temperature and should not
be exceeded. The output capacitor ripple current is
the inductor current, IL, minus the output current IO.
The RMS value of the ripple current flowing in the
output capacitance (continuous inductor current
mode operation) is given by:
IRMS
IL
√3
6
IL 0.289
ESL can be a problem by causing ringing in the low
megahertz region but can be controlled by choosing
low ESL capacitors, limiting lead length (PCB and
capacitor), and replacing one large device with
several smaller ones connected in parallel.
In conclusion, in order to meet the requirement of
output voltage ripple small and regulation loop
stability, ceramic capacitors with X5R or X7R
dielectrics are recommended due to their low ESR
and high ripple current ratings. The output ripple
VOUT determined by:
VOUT
VOUT VIN VOUT
VIN fOSC L
A 22uF ceramic
applications.
ESR
capacitor
1
8 fOSC COUT
can
satisfy
most
THERMAL CALCULATIONS
There are three types of losses associated with the
AS1308A step-down converter: switching losses,
conduction losses, and quiescent current losses.
Conduction losses are associated with the RDS(ON)
characteristics of the power output switching devices.
At full load, assuming continuous conduction mode
(CCM), a simplified form of the losses is given by:
PTOTAL
IO
R DSON HS
VO
R DSON LS
VIN
t SW F IO IQ
VIN
VO
VIN
IQ is the step-down converter quiescent current. The
term tSW is used to estimate the full load step-down
converter switching losses. For the condition where
the step-down converter is in dropout at 100% duty
cycle, the total device dissipation reduces to:
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
PTOTAL
IO R DSON HS
IQ VIN
Since RDS(ON), quiescent current, and switching
losses all vary with input voltage, the total losses
should be investigated over the complete input
voltage range. Given the total losses, the maximum
junction temperature can be derived from the ΘJA for
the DFN-10L package which is 45°C/W.
TJ MAX
PTOTAL ΘJA
AS1308A Rev.1.0
10/25/2008
TAMB
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
PACKAGE DESCRIPTION
Units: mm
Package
10-Lead Plastic TDFN-10L
AS1308A Rev.1.0
10/25/2008
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
PACKAGE DESCRIPTION
Units: mm
Package
10-Lead Plastic MSOP-10L
AS1308A Rev.1.0
10/25/2008
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AS1308A
1.2MHz, 2.0A Sync. Buck Converter
© ANISEM Semiconductor Co., Ltd
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ANISEM warrants performance of its semiconductor products to the specifications applicable at the time of sale in accordance with ANISEM’s
standard warranty. Testing and other quality control techniques are utilized to the extent ANISEM deems necessary to support this warranty.
Specific testing of all parameters of each device is not necessarily performed.
AS1308A Rev.1.0
10/25/2008
www.anisem.com
ANISEM Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2008 ANISEM All Rights Reserved.
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EV2300-1.0
1.2MHz, Sync. Boost Converter
FEATURES
GENERAL DESCRIPTION
High Efficiency: Up to 92%
The AS2300 is a 1.2MHz constant frequency,
1.2MHz Constant Switching Frequency
current mode PWM step-up converter. It can supply
[email protected] Output from 1 Single AA Cell;
3.3V output voltage at 100mA from a single AA Cell.
[email protected] Output from 2 AA cells
Low Start-up Voltage: 0.85V
The device integrates a main switch and a
Integrated main switch and sync. rectifier.
synchronous rectifier for high efficiency without an
2.5V to 5V Output Voltage Range
external Schottky diode. A switching frequency of
Automatic Pulse Skipping Mode Operation
1.2MHz allows the use of tiny, low profile inductors
Tiny External Components
and ceramic capacitors. The current mode PWM
<1 µA Shutdown Current
operation with internal compensation provides
Anti-ringing Control Reduces EMI
excellent line and load transient characteristics. The
Space Saving 6-Pin Thin SOT23 Package
AS2300 features Pulse Skipping Mode operation at
APPLICATIONS
light loads to avoid unacceptable ripple voltage.
Cellular and Smart Phones
The AS2300 is offered in a low profile (1 mm) small
Microprocessors and DSP Core Supplies
6-Pin SOT23 Package.
Wireless and DSL Modems
MP3 Player
Digital Still and Video Cameras
Portable Instruments
EV2300-1.0 EVALUATION BOARD
Figure1. High Performance Step-Up Converter
EV2300 Rev.1.0
6/25/2008
www.anisem.com
ANISEM Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2008 ANISEM All Rights Reserved.
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