ACTIVE-SEMI ACT4523AYH-T Wide-input sensorless cc/cv step-down dc/dc converter Datasheet

ACT4523A
Rev 0, 25-Jul-13
Wide-Input Sensorless CC/CV Step-Down DC/DC Converter
FEATURES
APPLICATIONS
•
•
•
•
•
•
•
• Car Charger/ Adaptor
• Rechargeable Portable Devices
• General-Purpose CC/CV Supply
40V Input Voltage Surge
36V Steady State Operation
Up to 3.5A Output Current
Output Voltage up to 12V
250kHz Switching Frequency
91% Efficiency (Vout = [email protected] at Vin = 12V)
Patented ActiveCC Sensorless Constant Current
Control
− Integrated Current Control Improves
Efficiency, Lowers Cost, and Reduces
Component Count
• Resistor Programmable
GENERAL DESCRIPTION
ACT4523A is a wide input voltage, high efficiency
ActiveCC step-down DC/DC converter that operates
in either CV (Constant Output Voltage) mode or CC
(Constant Output Current) mode. ACT4523A
provides up to 3.5A output current at 250kHz
switching frequency.
Active CC is a patented control scheme to achieve
highest accuracy with sensorless constant current
control. ActiveCC eliminates the expensive, high
accuracy current sense resistor, making it ideal for
battery charging applications and adaptors with
accurate current limit. The ACT4523A achieves
higher efficiency than traditional constant current
switching regulators by eliminating its associated
power loss on the sensing resistor. ACT4523A
provides OVP pin for output over voltage protection.
− Current Limit from 1.5A to 4.0A
− Patented Cable Compensation from 0 to
0.25Ω
• ±6.5% CC Accuracy
− Compensation of Input /Output Voltage Change
− Temperature Compensation
− Independent of inductance and Inductor DCR
• 2% Feedback Voltage Accuracy
• Advanced Feature Set
− Integrated Soft Start
− Thermal Shutdown
− Secondary Cycle-by-Cycle Current Limit
− Protection Against Shorted ISET Pin
• SOP-8EP Package
Protection features include cycle-by-cycle current
limit, thermal shutdown, and frequency foldback at
short circuit. The devices are available in a SOP8EP package and require very few external devices
for operation.
CC/CV Curve
VIN = 12V
Output Voltage (V)
5.0
ACT4523A-001
6.0
4.0
VIN = 24V
3.0
2.0
VIN = 18V
1.0
0.0
1.4
1.6
1.8
2.0
2.2
2.6
2.4
2.8
3.0
Output Current (A)
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Copyright © 2013 Active-Semi, Inc.
ACT4523A
Rev 0, 25-Jul-13
ORDERING INFORMATION
PART NUMBER
OPERATION TEMPERATURE RANGE
ACT4523AYH-T
-40°C to 85°C
PACKAGE
PINS
PACKING
SOP-8EP
8
TAPE & REEL
PIN CONFIGURATION
PIN DESCRIPTIONS
PIN
NAME
DESCRIPTION
1
HSB
High Side Bias Pin. This provides power to the internal high-side MOSFET gate driver.
Connect a 22nF capacitor from HSB pin to SW pin.
2
IN
Power Supply Input. Bypass this pin with a 10µF ceramic capacitor to GND, placed as
close to the IC as possible.
3
SW
4
GND
Ground. Connect this pin to a large PCB copper area for best heat dissipation. Return
FB, COMP, and ISET to this GND, and connect this GND to power GND at a single
point for best noise immunity.
5
FB
Feedback Input. The voltage at this pin is regulated to 0.808V. Connect to the resistor
divider between output and GND to set the output voltage.
6
COMP
7
OVP
OVP input. If the voltage at this pin exceeds 0.8V, the IC shuts down high-side switch.
8
ISET
Output Current Setting Pin. Connect a resistor from ISET to GND to program the
output current.
Exposed Pad
Heat Dissipation Pad. Connect this exposed pad to large ground copper area with
copper and vias.
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Power Switching Output to External Inductor.
Error Amplifier Output. This pin is used to compensate the converter.
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Copyright © 2013 Active-Semi, Inc.
ACT4523A
Rev 0, 25-Jul-13
ABSOLUTE MAXIMUM RATINGSc
PARAMETER
VALUE
UNIT
-0.3 to 40
V
SW to GND
-1 to VIN + 1
V
HSB to GND
VSW - 0.3 to VSW + 7
V
-0.3 to + 6
V
46
°C/W
Operating Junction Temperature
-40 to 150
°C
Storage Junction Temperature
-55 to 150
°C
300
°C
IN to GND
FB, ISET, COMP to GND
Junction to Ambient Thermal Resistance
Lead Temperature (Soldering 10 sec.)
c: Do not exceed these limits to prevent damage to the device. Exposure to absolute maximum rating conditions for long periods may
affect device reliability.
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Copyright © 2013 Active-Semi, Inc.
ACT4523A
Rev 0, 25-Jul-13
ELECTRICAL CHARACTERISTICS
(VIN = 12V, TA = 25°C, unless otherwise specified.)
PARAMETER
TEST CONDITIONS
Input Voltage
MIN
TYP
10
Input Voltage Surge
36
V
40
V
9.7
V
Input Voltage Rising
VIN UVLO Hysteresis
Input Voltage Falling
1.1
Standby Supply Current
VFB = 1V
0.9
1.4
mA
808
824
mV
792
Internal Soft-Start Time
Error Amplifier Transconductance
VFB = VCOMP = 0.8V,
∆ICOMP = ± 10µA
Error Amplifier DC Gain
9.4
UNIT
VIN UVLO Turn-On Voltage
Feedback Voltage
9.0
MAX
V
400
µs
650
µA/V
4000
V/V
Switching Frequency
VFB = 0.808V
250
kHz
Foldback Switching Frequency
VFB = 0V
36
kHz
Maximum Duty Cycle
85
%
Minimum On-Time
190
ns
COMP to Current Limit Transconductance
VCOMP = 1.2V
3.9
A/V
Secondary Cycle-by-Cycle Current Limit
Duty = 0.5
5.2
A
Slope Compensation
Duty = DMAX
1.4
A
1.0
V
ISET Voltage
ISET to IOUT DC Room Temp Current Gain
IOUT / ISET, RISET = 7.87kΩ
20000
A/A
CC Controller DC Accuracy
RISET = 7.87kΩ, VOUT = 4.0V
2650
mA
OVP pin Voltage
OVP Pin Rising
0.8
V
85
mΩ
High-Side Switch ON-Resistance
SW Off Leakage Current
Vin = VSW = 0V
Thermal Shutdown Temperature
Temperature Rising
155
°C
Thermal Shutdown Temperature Hysteresis
Temperature Falling
25
°C
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-4-
1
10
µA
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Copyright © 2013 Active-Semi, Inc.
ACT4523A
Rev 0, 25-Jul-13
FUNCTIONAL BLOCK DIAGRAM
FUNCTIONAL DESCRIPTION
regulating output voltage to regulating output
current, and the output voltage will drop with
increasing load.
CV/CC Loop Regulation
As seen in Functional Block Diagram, the
ACT4523A is a peak current mode pulse width
modulation (PWM) converter with CC and CV
control. The converter operates as follows:
The Oscillator normally switches at 250kHz.
However, if FB voltage is less than 0.6V, then the
switching frequency decreases until it reaches a
typical value of 36kHz at VFB = 0.15V.
A switching cycle starts when the rising edge of the
Oscillator clock output causes the High-Side Power
Switch to turn on and the Low-Side Power Switch to
turn off. With the SW side of the inductor now
connected to IN, the inductor current ramps up to
store energy in the magnetic field. The inductor
current level is measured by the Current Sense
Amplifier and added to the Oscillator ramp signal. If
the resulting summation is higher than the COMP
voltage, the output of the PWM Comparator goes
high. When this happens or when Oscillator clock
output goes low, the High-Side Power Switch turns
off.
Over Voltage Protection
The ACT4523A has an OVP pin. If the voltage at this
pin exceeds 0.8V, the IC shuts down high side switch.
Thermal Shutdown
The ACT4523A disables switching when its junction
temperature exceeds 155°C and resumes when the
temperature has dropped by 25°C.
At this point, the SW side of the inductor swings to
a diode voltage below ground, causing the inductor
current to decrease and magnetic energy to be
transferred to output. This state continues until the
cycle starts again. The High-Side Power Switch is
driven by logic using HSB as the positive rail. This
pin is charged to VSW + 5V when the Low-Side
Power Switch turns on. The COMP voltage is the
integration of the error between FB input and the
internal 0.808V reference. If FB is lower than the
reference voltage, COMP tends to go higher to
increase current to the output. Output current will
increase until it reaches the CC limit set by the ISET
resistor. At this point, the device will transition from
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Copyright © 2013 Active-Semi, Inc.
ACT4523A
Rev 0, 25-Jul-13
APPLICATIONS INFORMATION
Inductor Selection
Output Voltage Setting
The inductor maintains a continuous current to the
output load. This inductor current has a ripple that is
dependent on the inductance value:
Figure 1:
Output Voltage Setting
Higher inductance reduces the peak-to-peak ripple
current. The trade off for high inductance value is
the increase in inductor core size and series
resistance, and the reduction in current handling
capability. In general, select an inductance value L
based on ripple current requirement:
L=
Figure 1 shows the connections for setting the
output voltage. Select the proper ratio of the two
feedback resistors RFB1 and RFB2 based on the
output voltage. Adding a capacitor in parallel with
RFB1 helps the system stability. Typically, use RFB2 ≈
10kΩ and determine RFB1 from the following
equation:
⎛ V
⎞
R FB1 = R FB 2 ⎜ OUT − 1 ⎟
0
.
808
V
⎝
⎠
VOUT × (VIN _VOUT )
VIN fSW ILOADMAX K RIPPLE
(2)
where VIN is the input voltage, VOUT is the output
voltage, fSW is the switching frequency, ILOADMAX is
the maximum load current, and KRIPPLE is the ripple
factor. Typically, choose KRIPPLE = 30% to
correspond to the peak-to-peak ripple current being
30% of the maximum load current.
With a selected inductor value the peak-to-peak
inductor current is estimated as:
(1)
CC Current Setting
ILPK _ PK =
ACT4523A constant current value is set by a
resistor connected between the ISET pin and GND.
The CC output current is linearly proportional to the
current flowing out of the ISET pin. The voltage at
ISET is roughly 1.1V and the current gain from
ISET to output is roughly 21000 (21mA/1µA). To
determine the proper resistor for a desired current,
please refer to Figure 2 below.
VOUT × (VIN _VOUT )
L × VIN × fSW
(3)
The peak inductor current is estimated as:
1
ILPK = ILOADMAX + ILPK _ PK
2
(4)
The selected inductor should not saturate at ILPK.
The maximum output current is calculated as:
Figure 2:
Curve for Programming Output CC Current
IOUTMAX = ILIM _
Output Current vs. RISET
1
I _
2 LPK PK
(5)
4500
ACT4523A-002
4000
Output Current (mA)
3500
3000
LLIM is the internal current limit, which is typically
4.5A, as shown in Electrical Characteristics Table.
External High Voltage Bias Diode
It is recommended that an external High Voltage
Bias diode be added when the system has a 5V
fixed input or the power supply generates a 5V
output. This helps improve the efficiency of the
regulator. The High Voltage Bias diode can be a
low cost one such as IN4148 or BAT54.
2500
2000
1500
1000
VIN = 24V, VOUT = 4V
500
2
6
10
14
18
22
26
Figure 3:
RISET (kΩ)
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External High Voltage Bias Diode
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Copyright © 2013 Active-Semi, Inc.
ACT4523A
Rev 0, 25-Jul-13
APPLICATIONS INFORMATION CONT’D
For ceramic output capacitor, typically choose a
capacitance of about 22µF. For tantalum or
electrolytic capacitors, choose a capacitor with less
than 50mΩ ESR.
Rectifier Diode
Use a Schottky diode as the rectifier to conduct
current when the High-Side Power Switch is off.
The Schottky diode must have current rating higher
than the maximum output current and a reverse
voltage rating higher than the maximum input
voltage.
This diode is also recommended for high duty cycle
operation and high output voltage applications.
Input Capacitor
The input capacitor needs to be carefully selected
to maintain sufficiently low ripple at the supply input
of the converter. A low ESR capacitor is highly
recommended. Since large current flows in and out
of this capacitor during switching, its ESR also
affects efficiency.
The input capacitance needs to be higher than
10µF. The best choice is the ceramic type,
however, low ESR tantalum or electrolytic types
may also be used provided that the RMS ripple
current rating is higher than 50% of the output
current. The input capacitor should be placed close
to the IN and G pins of the IC, with the shortest
traces possible. In the case of tantalum or
electrolytic types, they can be further away if a
small parallel 0.1µF ceramic capacitor is placed
right next to the IC.
Output Capacitor
The output capacitor also needs to have low ESR to
keep low output voltage ripple. The output ripple
voltage is:
VRIPPLE = IOUTMAX K RIPPLE RESR +
VIN
2
28 × fSW LC OUT
(6)
Where IOUTMAX is the maximum output current,
KRIPPLE is the ripple factor, RESR is the ESR of the
output capacitor, fSW is the switching frequency, L is
the inductor value, and COUT is the output
capacitance. In the case of ceramic output
capacitors, RESR is very small and does not
contribute to the ripple. Therefore, a lower
capacitance value can be used for ceramic type. In
the case of tantalum or electrolytic capacitors, the
ripple is dominated by RESR multiplied by the ripple
current. In that case, the output capacitor is chosen
to have sufficiently low ESR.
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ACT4523A
Rev 0, 25-Jul-13
STABILITY COMPENSATION
If RCOMP is limited to 15kΩ, then the actual cross
over frequency is 6.58 / (VOUTCOUT). Therefore:
Figure 4:
Stability Compensation
C COMP = 6 . 45 × 10
R ESRCOUT ≥ (Min
c: CCOMP2 is needed only for high ESR output capacitor
C COMP 2 =
G
EA
2 π A VEA C
The second pole P2 is the output pole:
I OUT
fP 2 =
2 π V OUT C OUT
fZ 1 =
And finally, the third pole is due to RCOMP and
CCOMP2 (if CCOMP2 is used):
fP 3 =
1
(11)
2πR COMP C COMP2
(12)
2 . 83 × 10
R COMP
Innovative PowerTM
C OUT R ESRCOUT
R COMP
(16)
RCOMP CCOMP CCOMP2c
VOUT
COUT
2.5V
47μF Ceramic CAP
5.6kΩ
3.3V
47μF Ceramic CAP
6.2kΩ
2.2nF
None
5V
47μF Ceramic CAP
12kΩ
2.2nF
None
2.5V
220μF/10V/30mΩ
20kΩ
2.2nF
47pF
3.3V
220μF/10V/30mΩ
20kΩ
2.2nF
47pF
5V
220μF/10V/30mΩ
20kΩ
2.2nF
47pF
2.2nF
None
To compensate for resistive voltage drop across the
charger's output cable, the ACT4523A integrates a
simple, user-programmable cable voltage drop
compensation using the impedance at the FB pin.
Use the curve in Figure 5 to choose the proper
feedback resistance values for cable compensation.
5
(F)
(15)
Output Cable Resistance Compensation
STEP 2. Set the zero fZ1 at 1/4 of the cross over
frequency. If RCOMP is less than 15kΩ, the equation
for CCOMP is:
C COMP =
(Ω)
The constant-current control loop is internally
compensated over the 1500mA-3000mA output
range. No additional external compensation is
required to stabilize the CC current.
2 π V OUT C OUT f SW
10 G EA G COMP × 0 . 808 V
(Ω)
)
CC Loop Stability
STEP 1. Set the cross over frequency at 1/10 of the
switching frequency via RCOMP:
= 5 . 12 × 10 7 VOUT C OUT
,0 . 006 × VOUT
c: CCOMP2 is needed for high ESR output capacitor.
CCOMP2 ≤ 47pF is recommended.
The following steps should be used to compensate
the IC:
R COMP =
_6
Typical Compensation for Different Output
Voltages and Output Capacitors
(9)
(10)
2 π R COMP C COMP
1 . 77 × 10
C OUT
Table 1:
The first zero Z1 is due to RCOMP and CCOMP:
1
(14)
Table 1 shows some calculated results based on
the compensation method above.
(8)
COMP
(F)
Though CCOMP2 is unnecessary when the output
capacitor has sufficiently low ESR, a small value
CCOMP2 such as 100pF may improve stability against
PCB layout parasitic effects.
(7)
The dominant pole P1 is due to CCOMP:
fP 1 =
VOUT C OUT
And the proper value for CCOMP2 is:
The feedback loop of the IC is stabilized by the
components at the COMP pin, as shown in Figure
4. The DC loop gain of the system is determined by
the following equation:
0 . 808 V
A VEA G COMP
I OUT
6
STEP 3. If the output capacitor’s ESR is high
enough to cause a zero at lower than 4 times the
cross over frequency, an additional compensation
capacitor CCOMP2 is required. The condition for using
CCOMP2 is:
c
A VDC =
_
(13)
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Copyright © 2013 Active-Semi, Inc.
ACT4523A
Rev 0, 25-Jul-13
STABILITY COMPENSATION CONT’D
RFB1 is the high side resistor of voltage divider.
power GND with vias or short and wide path.
In the case of high RFB1 used, the frequency
compensation
needs
to
be
adjusted
correspondingly. As show in Figure 6, adding a
capacitor in paralleled with RFB1 or increasing the
compensation capacitance at COMP pin helps the
system stability.
3) Return FB, COMP and ISET to signal GND pin,
and connect the signal GND to power GND at a
single point for best noise immunity. Connect
exposed pad to power ground copper area with
copper and vias.
4) Use copper plane for power GND for best heat
dissipation and noise immunity.
Figure 5:
5) Place feedback resistor close to FB pin.
Cable Compensation at Various Resistor Divider
Values
6) Use short trace connecting HSB-CHSB-SW loop
Delta Output Voltage vs. Output Current
Delta Output Voltage (mV)
400
350
1
R FB
=3
300
1
R FB
250
200
00
R FB1
150
R FB1
100
k
=2
40
k
=2
Figure 7 shows an example of PCB layout.
ACT4523A-003
450
00k
= 15
0k
RFB1 = 100k
50
RFB1 = 51k
0
0
0.3
0.6
0.9
1.2
1.5
1.8
2.1
2.4
Output Current (A)
Figure 6:
Frequency Compensation for High RFB1
Figure 7: PCB Layout
PC Board Layout Guidance
Figure 9 gives one typical car charger application
schematic and associated BOM list.
When laying out the printed circuit board, the
following checklist should be used to ensure proper
operation of the IC.
1) Arrange the power components to reduce the
AC loop size consisting of CIN, IN pin, SW pin
and the schottky diode.
2) Place input decoupling ceramic capacitor CIN as
close to IN pin as possible. CIN is connected
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ACT4523A
Rev 0, 25-Jul-13
Figure 8:
Typical Application Circuit for 5V/2.4A Car Charger
Table 2:
BOM List for 5V/2.4A Car Charger
ITEM REFERENCE
DESCRIPTION
MANUFACTURER
QTY
1
U1
IC, ACT4523AYH, SOP-8EP
Active-Semi
1
2
C1
Capacitor, Electrolytic, 47µF/50V, 6.3х7mm
Murata, TDK
1
3
C2
Capacitor, Ceramic, 10µF/50V, 1206, SMD
Murata, TDK
1
4
C3
Capacitor, Ceramic, 2.2nF/6.3V, 0603, SMD
Murata, TDK
1
5
C4
Capacitor, Ceramic, 22nF/50V, 1206, SMD
Murata, TDK
1
6
C5
Capacitor, Ceramic, 1nF/10V, 0603, SMD
Murata, TDK
1
7
C6
Capacitor, Ceramic, 10uF/10V, 0603, SMD
Murata, TDK
1
8
C7
Capacitor, Electrolytic, 220uF/10V, 6.3х7mm
Murata, TDK
1
9
L1
Inductor, 30µH, 5A, 20%, SMD
Tyco Electronics
1
10
D1
Diode, Schottky, 40V/5A, SK54BL
Diodes
1
11
R1
Chip Resistor, 7.87kΩ, 0603, 1%
Murata, TDK
1
12
R2
Chip Resistor, 51kΩ, 0603, 1%
Murata, TDK
1
13
R3
Chip Resistor, 20kΩ, 0603, 5%
Murata, TDK
1
14
R4
Chip Resistor, 9.76kΩ, 0603, 1%
Murata, TDK
1
15
R5
Chip Resistor, 100kΩ, 0603, 1%
Murata, TDK
1
16
R6
Chip Resistor, 15kΩ, 0603, 1%
Murata, TDK
1
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ACT4523A
Rev 0, 25-Jul-13
TYPICAL PERFORMANCE CHARACTERISTICS
(Schematic as show in Figure 8, Ta = 25°C, unless otherwise specified)
Switching Frequency vs. Input Voltage
Efficiency vs. Load Current
Efficiency (%)
85
Switching Frequency (kHz)
VIN =12V
90
80
VIN =18V
75
VIN =24V
70
65
60
ACT4523A-005
290
ACT4523A-004
95
280
270
260
250
240
230
220
210
0
0.4
0.8
1.2
1.6
2.0
2.4
2.8
3.2
3.6
15
10
20
Load Current(A)
VOUT = 5V
VIN = 12V
IISET = 2.65A
2700
CC Current (mA)
Switching Frequency (kHz)
200
150
100
50
2680
2660
2640
2620
2600
2580
100
200
300
400
500
600
700
800
2560
-20
900
0
Feedback Voltage (mV)
20
40
60
80
100
120
140
Temperature (°C)
CC Current vs. Input Voltage
Maximum Peak Current vs. Duty Cycle
VOUT = 5V
IISET = 2.65A
2700
ACT4523A-009
8.0
ACT4523A-008
CC Current (mA)
ACT4523A-007
250
2750
40
CC Current vs. Temperature
2720
ACT4523A-006
300
2800
35
Input Voltage (V)
Switching Frequency vs. Feedback Voltage
0
0
30
25
7.0
6.0
5.0
2650
4.0
2600
3.0
2550
2.0
1.0
2500
10
15
20
25
30
35
20
40
40
50
60
70
80
90
Duty Cycle
Input Voltage (V)
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30
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ACT4523A
Rev 0, 25-Jul-13
TYPICAL PERFORMANCE CHARACTERISTICS CONT’D
(Schematic as show in Figure 8, Ta = 25°C, unless otherwise specified)
Standby Current vs. Input Voltage
(FB=1V)
Feedback Voltage vs. Input Voltage
0.818
Standby Supply Current (mA)
Standby Current (µA)
1120
1080
1040
1000
960
8
12
16
20
24
28
32
36
ACT4523A-011
ACT4523A-010
1160
0.815
0.812
0.809
0.806
0.803
0.800
8
40
12
16
24
28
32
36
40
Input Voltage (V)
Input Voltage (V)
Start up into CC mode
Reverse Leakage Current (VIN Floating)
120
ACT4523A-013
ACT4523A-012
160
Reverse Leakage Current(µA)
20
VOUT = 5V
RLORD = 1.5Ω
IISET = 2.65A
VIN = 12V
CH1
80
40
CH2
0
0
1.0
2.0
3.0
4.0
CH1: VOUT, 2V/div
CH2: IOUT, 1A/div
TIME: 400µs/div
5.0
VOUT(V)
Start up into CC mode
ACT4523A-015
ACT4523A-014
VOUT = 5V
RLORD = 1.5Ω
IISET = 2.65A
VIN = 24V
SW vs. Output Voltage Ripples
VIN = 12V
VOUT = 5V
IOUT = 2.4A
CH1
CH1
CH2
CH2
CH1: VOUT, 2V/div
CH2: IOUT, 1A/div
TIME: 400µs/div
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CH1: VOUT Ripple, 20mV/div
CH2: SW, 5V/div
TIME: 2µs/div
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ACT4523A
Rev 0, 25-Jul-13
TYPICAL PERFORMANCE CHARACTERISTICS CONT’D
(Schematic as show in Figure 8, Ta = 25°C, unless otherwise specified)
SW vs. Output Voltage Ripple
Start up with VIN
CH1
ACT4523A-017
ACT4523A-016
VIN = 24V
VOUT = 5V
IOUT = 2.4A
VIN = 12V
VOUT = 5V
IISET = 2.65A
CH1
CH2
CH2
CH1: VIN, 5V/div
CH2: VOUT, 2V/div
TIME: 400µs//div
CH1: VRIPPLE, 20mV/div
CH2: SW, 10V/div
TIME: 2µs/div
Load transient (80mA-1A-80mA)
Start up with VIN
ACT4523A-019
ACT4523A-018
VIN = 24V
VOUT = 5V
IISET = 2.65A
VIN = 12V
VOUT = 5V
IISET = 2.65A
CH1
CH1
CH2
CH2
CH1: VIN, 10V/div
CH2: VOUT, 2V/div
TIME: 400µs//div
CH1: VOUT, 50mV/div
CH2: IOUT, 1A/div
TIME: 400µs//div
Short Circuit
Load transient (1A-2.4A-1A)
VIN = 12V
VOUT = 5V
IISET = 2.65A
CH1
ACT4523A-021
CH1
ACT4523A-020
VIN = 24V
VOUT = 5V
IISET = 2.65A
CH2
CH2
CH1: VOUT, 100mV/div
CH2: IOUT, 1A/div
TIME: 400µs//div
Innovative PowerTM
CH1: VOUT, 2V/div
CH2: IL, 1A/div
TIME: 100µs//div
- 13 -
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Copyright © 2013 Active-Semi, Inc.
ACT4523A
Rev 0, 25-Jul-13
TYPICAL PERFORMANCE CHARACTERISTICS CONT’D
(Schematic as show in Figure 8, Ta = 25°C, unless otherwise specified)
Short Circuit
Short Circuit Recovery
ACT4523A-023
ACT4523A-022
VIN = 24V
VOUT = 5V
IISET= 2.65A
CH1
VIN = 12V
VOUT = 5V
IISET = 2.65A
CH1
CH2
CH2
CH1: VOUT, 2V/div
CH2: IL, 1A/div
TIME: 400µs//div
CH1: VOUT, 2V/div
CH2: IL, 1A/div
TIME: 100µs//div
OVP Circuit
Short Circuit Recovery
VIN = 12V
VOUT = 5V
IISET = 2.65A
CH1
ACT4523A-025
ACT4523A-024
VIN = 24V
VOUT = 5V
IISET = 2.65A
CH1
CH2
CH2
CH1: VIN, 5V/div
CH2: VOUT, 2V/div
TIME: 10ms//div
CH1: VOUT, 2V/div
CH2: IL, 1A/div
TIME: 400µs//div
Innovative PowerTM
- 14 -
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Copyright © 2013 Active-Semi, Inc.
ACT4523A
Rev 0, 25-Jul-13
PACKAGE OUTLINE
SOP-8EP PACKAGE OUTLINE AND DIMENSIONS
SYMBOL
DIMENSION IN
MILLIMETERS
DIMENSION IN
INCHES
MIN
MAX
MIN
MAX
A
1.350
1.700
0.053
0.067
A1
0.000
0.100
0.000
0.004
A2
1.350
1.550
0.053
0.061
b
0.330
0.510
0.013
0.020
c
0.170
0.250
0.007
0.010
D
4.700
5.100
0.185
0.200
D1
3.202
3.402
0.126
0.134
E
3.800
4.000
0.150
0.157
E1
5.800
6.200
0.228
0.244
E2
2.313
2.513
0.091
0.099
e
1.270 TYP
0.050 TYP
L
0.400
1.270
0.016
0.050
θ
0°
8°
0°
8°
Note:
1. Dimension D does not include mold flash, protrusions or gate burrs. Mold flash, protrusions or gate burrs shall not exceed
0.15mm per end.
2. Dimension E does not include interlead flash or protrusion. Interlead flash or protrusion shall not exceed 0.25mm per side.
Active-Semi, Inc. reserves the right to modify the circuitry or specifications without notice. Users should evaluate each
product to make sure that it is suitable for their applications. Active-Semi products are not intended or authorized for use
as critical components in life-support devices or systems. Active-Semi, Inc. does not assume any liability arising out of
the use of any product or circuit described in this datasheet, nor does it convey any patent license.
Active-Semi and its logo are trademarks of Active-Semi, Inc. For more information on this and other products, contact
[email protected] or visit http://www.active-semi.com.
is a registered trademark of Active-Semi.
Innovative PowerTM
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Copyright © 2013 Active-Semi, Inc.
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