ACTIVE-SEMI ACT4514SH-T

ACT4514
Active-Semi
Rev 1, 21-Jul-11
Wide-Input Sensorless CC/CV Step-Down DC/DC Converter
FEATURES
APPLICATIONS
•
•
•
•
• Car Charger
• Rechargeable Portable Devices
• General-Purpose CC/CV Power Supply
Up to 40V Input Voltage
Up to 1.5A Constant Output Current
Output Voltage up to 12V
Patent Pending ActiveCC Constant Current
Control
− Integrated Current Control Improves
Efficiency, Lowers Cost, and Reduces
Component Count
• Resistor Programmable Outputs
GENERAL DESCRIPTION
ACT4514 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. ACT4514
provides up to 1.5A output current at 210kHz
switching frequency.
− Current Limit from 400mA to 1500mA
− Patented cable compensation from DC Cable
•
•
•
•
•
ActiveCC is a patent-pending control scheme to
achieve highest accuracy sensorless constant
current control. ActiveCC eliminates the expensive,
high accuracy current sense resistor, making it ideal
for battery charging applications and highbrightness LED drive for architectural lighting. The
ACT4514 achieves higher efficiency than traditional
constant current switching regulators by eliminating
the sense resistor and its associated power loss.
Compensation from 0Ω to 0.5Ω
2% Feedback Voltage Accuracy
Up to 93% Efficiency
210kHz Switching Frequency Eases EMI Design
Advanced Feature Set
− Integrated Soft Start
− Thermal Shutdown
− Secondary Cycle-by-Cycle Current Limit
− Protection Against Shorted ISET Pin
SOP-8 Package
Protection features include cycle-by-cycle current
limit, thermal shutdown, and frequency foldback at
short circuit. The devices are available in a SOP-8
package and require very few external devices for
operation.
CC/CV Curve vs. Load Current
ACT4514-001
6.0
V0UT = 5V
Output Voltage (V)
5.0
4.0
3.0
VIN = 12V
VIN = 24V
2.0
1.0
0.0
0
150
300
450
600
750
900
IOUT Current (mA)
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Copyright © 2011 Active-Semi, Inc.
ACT4514
Active-Semi
Rev 1, 21-Jul-11
ORDERING INFORMATION
PART NUMBER
TEMPERATURE RANGE
PACKAGE
PINS
PACKING
ACT4514SH-T
-40°C to 85°C
SOP-8
8
TAPE & REEL
PIN CONFIGURATION
HSB
1
8
ISET
IN
2
7
EN
ACT4514
SW
3
6
COMP
GND
4
5
FB
SOP-8
PIN DESCRIPTIONS
PIN
NAME
1
HSB
2
IN
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
EN
8
ISET
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DESCRIPTION
High Voltage Bias Pin. This provides power to the internal high-side MOSFET gate
driver. Connect a 10nF capacitor from HSB pin to SW pin.
Power Supply Input. Bypass this pin with a 10µF ceramic capacitor to GND, placed as
close to the IC as possible.
Power Switching Output to External Inductor.
Error Amplifier Output. This pin is used to compensate the converter.
Enable Input. EN is pulled up to 5V with a 4μA current, and contains a precise 0.8V
logic threshold. Drive this pin to a logic-high or leave unconnected to enable the IC.
Drive to a logic-low to disable the IC and enter shutdown mode.
Output Current Setting Pin. Connect a resistor from ISET to GND to program the
output current.
-2-
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Copyright © 2011 Active-Semi, Inc.
ACT4514
Active-Semi
Rev 1, 21-Jul-11
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
105
°C/W
Operating Junction Temperature
-40 to 150
°C
Storage Junction Temperature
-55 to 150
°C
300
°C
IN to GND
FB, EN, 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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ACT4514
Active-Semi
Rev 1, 21-Jul-11
ELECTRICAL CHARACTERISTICS
(VIN = 14V, TA = 25°C, unless otherwise specified.)
PARAMETER
TEST CONDITIONS
Input Voltage
MIN
TYP
10
MAX
UNIT
40
V
9.65
V
VIN UVLO Turn-On Voltage
Input Voltage Rising
VIN UVLO Hysteresis
Input Voltage Falling
VIN OVP Turn-Off Voltage
Input Voltage Rising
VIN OVP Hysteresis
Input Voltage Falling
1.75
V
VEN = 3V, VFB = 1V
1.0
mA
VEN = 3V, VO = 5V, No load
2.5
mA
VEN = 0V
75
100
µA
808
824
mV
Standby Supply Current
Shutdown Supply Current
Feedback Voltage
9.05
1.1
32.5
792
Internal Soft-Start Time
Error Amplifier Transconductance
VFB = VCOMP = 0.8V, ∆ICOMP = ± 10µA
Error Amplifier DC Gain
Switching Frequency
VFB = 0.808V
Foldback Switching Frequency
VFB = 0V
9.35
190
V
34.5
36.5
400
µs
650
µA/V
4000
V/V
210
240
30
Maximum Duty Cycle
82
V
kHz
kHz
85
88
%
Minimum On-Time
200
ns
COMP to Current Limit Transconductance VCOMP = 1.2V
1.75
A/V
Switch Current Limit
Duty = 50%
1.8
A
Slope Compensation
Duty = DMAX
0.75
A
1
V
25000
A/A
ISET Voltage
ISET to IOUT DC Room Temp Current
Gain
IOUT / ISET
EN Threshold Voltage
EN Pin Rising
EN Hysteresis
EN Pin Falling
EN Internal Pull-up Current
High-Side Switch ON-Resistance
SW Off Leakage Current
VEN = VSW = 0V
Thermal Shutdown Temperature
Temperature Rising
Innovative PowerTM
-4-
0.75
0.8
0.85
V
80
mV
4
µA
0.3
Ω
1
155
10
µA
°C
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Copyright © 2011 Active-Semi, Inc.
ACT4514
Active-Semi
Rev 1, 21-Jul-11
FUNCTIONAL BLOCK DIAGRAM
IN
AVIN
BANDGAP,
REGULATOR,
&
SHUTDOWN
CONTROL
EN
PVIN
OSCILLATOR
VREF = 0.808V
EMI
CONTROL
HSB
PWM
CONTROLLER
VREF = 0.808V
FB
SW
+
CC
CONTROL
COMP
ISET
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 ACT4514
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 200kHz.
However, if FB voltage is less than 0.6V, then the
switching frequency decreases until it reaches a
typical value of 30kHz 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.
Enable Pin
The ACT4514 has an enable input EN for turning
the IC on or off. The EN pin contains a precision
0.8V comparator with 75mV hysteresis and a 4µA
pull-up current source. The comparator can be used
with a resistor divider from VIN to program a startup
voltage higher than the normal UVLO value. It can
be used with a resistor divider from VOUT to disable
charging of a deeply discharged battery, or it can be
used with a resistor divider containing a thermistor
to provide a temperature-dependent shutoff
protection for over temperature battery. The
thermistor should be thermally coupled to the
battery pack for this usage.
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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If left floating, the EN pin will be pulled up to roughly
5V by the internal 4µA current source. It can be
driven from standard logic signals greater than
0.8V, or driven with open-drain logic to provide
digital on/off control.
Thermal Shutdown
The ACT4514 disables switching when its junction
temperature exceeds 155°C and resumes when the
temperature has dropped by 20°C.
-5-
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Copyright © 2011 Active-Semi, Inc.
ACT4514
Active-Semi
Rev 1, 21-Jul-11
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
output voltage. Select the proper ratio of the
feedback resistors RFB1 and RFB2 based on
output voltage. Typically, use RFB2 ≈ 10kΩ
determine RFB1 from the following equation:
⎛ V
⎞
RFB1 = RFB2 ⎜ OUT −1⎟
⎝ 0.808V ⎠
the
two
the
and
(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.
(1)
With a selected inductor value the peak-to-peak
inductor current is estimated as:
CC Current Setting
ACT4514 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 1V and the current gain from ISET to output
is roughly 25000 (25mA/1µA). To determine the
proper resistor for a desired current, please refer to
Figure 2 below.
ILPK _ PK =
VOUT × (VIN _VOUT )
L × VIN × fSW
1
ILPK = ILOADMAX + ILPK _ PK
2
IOUTMAX = ILIM _
Output Current vs. RISET
ACT4514-002
1600
1400
(4)
The selected inductor should not saturate at ILPK.
The maximum output current is calculated as:
Curve for Programming Output CC Current
1800
(3)
The peak inductor current is estimated as:
Figure 2:
Output Current (mA)
VOUT × (VIN _VOUT )
VIN fSW ILOADMAX K RIPPLE
1
I _
2 LPK PK
(5)
LLIM is the internal current limit, which is typically
2.5A, as shown in Electrical Characteristics Table.
1200
1000
800
600
External High Voltage Bias Diode
400
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.
200
0
0
10
20
30
40
50
60
70
80
90
RISET (kΩ)
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Copyright © 2011 Active-Semi, Inc.
ACT4514
Active-Semi
Rev 1, 21-Jul-11
APPLICATIONS INFORMATION CONT’D
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.
Figure 3:
External High Voltage Bias Diode
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
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ACT4514
Active-Semi
Rev 1, 21-Jul-11
STABILITY COMPENSATION
If RCOMP is limited to 15kΩ, then the actual cross
over frequency is 3.4 / (VOUTCOUT). Therefore:
Figure 4:
Stability Compensation
CCOMP = 1.2 ×10 −5 VOUTCOUT
(14)
(F)
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:
⎞
⎛ 1.1 × 10 −6
,0.012 × VOUT ⎟⎟
RESRCOUT ≥ Min⎜⎜
⎠
⎝ COUT
c: CCOMP2 is needed only for high ESR output capacitor
AVDC
The dominant pole P1 is due to CCOMP:
G EA
fP1 =
2 π AVEA C COMP
The second pole P2 is the output pole:
I OUT
fP 2 =
2 π V OUT C OUT
The first zero Z1 is due to RCOMP and CCOMP:
1
f Z1 =
2π RCOMP CCOMP2
CCOMP 2 =
1
(7)
(8)
Table 1:
Typical Compensation for Different Output
Voltages and Output Capacitors
(9)
(10)
The following steps should be used to compensate
the IC:
STEP 1. Set the cross over frequency at 1/10 of the
switching frequency via RCOMP:
R COMP =
(Ω)
C COMP
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(F)
COUT
RCOMP
CCOMP CCOMP2c
2.5V
22μF Ceramic
8.2kΩ
2.2nF
3.3V
22μF Ceramic
12kΩ
1.5nF
None
5V
22μF Ceramic
15kΩ
1.5nF
None
None
2.5V
47μF SP CAP
15kΩ
1.5nF
None
3.3V
47μF SP CAP
15kΩ
1.8nF
None
5V
47μF SP CAP
15kΩ
2.7nF
None
2.5V
470μF/6.3V/30mΩ
15kΩ
15nF
47pF
3.3V
470μF/6.3V/30mΩ
15kΩ
22nF
47pF
5V
470μF/6.3V/30mΩ
15kΩ
27nF
47pF
CC Loop Stability
The constant-current control loop is internally
compensated over the 400mA-1500mA output
range. No additional external compensation is
required to stabilize the CC current.
(12)
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:
1 .8 × 10 −5
=
R COMP
VOUT
c: CCOMP2 is needed for high ESR output capacitor.
CCOMP2 ≤ 47pF is recommended.
2 πVOUT C OUT fSW
10 G EA GCOMP × 0 .808 V
= 2 . 75 × 10 8 VOUT C OUT
(16)
Table 2 shows some calculated results based on
the compensation method above.
(11)
2πR COMP C COMP2
COUT RESRCOUT
RCOMP
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.
And finally, the third pole is due to RCOMP and
CCOMP2 (if CCOMP2 is used):
fP 3 =
(15)
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
3. The DC loop gain of the system is determined by
the following equation:
0 . 808 V
=
AVEA G COMP
I OUT
(Ω)
Output Cable Resistance Compensation
To compensate for resistive voltage drop across the
charger's output cable, the ACT4514 integrates a
(13)
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ACT4514
Active-Semi
Rev 1, 21-Jul-11
STABILITY COMPENSATION CONT’D
simple, user-programmable cable voltage drop
compensation using the impedance at the FB pin.
Use the curve in Figure 4 to choose the proper
feedback resistance values for cable compensation.
RFB1 is the high side resistor of voltage divider.
and the schottky diode.
2) Place input decoupling ceramic capacitor CIN as
close to IN pin as possible. CIN is connected
power GND with vias or short and wide path.
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.
In the case of high RFB1 used, the frequency
compensation
needs
to
be
adjusted
correspondingly. As show in Figure 6, adding a
capacitor in paralled with RFB1 or increasing the
compensation capacitance at COMP pin helps the
system stability.
4) Use copper plane for power GND for best heat
dissipation and noise immunity.
5) Place feedback resistor close to FB pin.
Figure 5:
6) Use short trace connecting HSB-CHSB-SW loop
Cable Compensation at Various Resistor Divider
Values
Figure 7 shows an example of PCB layout.
Delta Output Voltage vs. Output Current
Delta Output Voltage (V)
VIN = 14V
V0UT = 5V
IISET = 1.5A
0.56
B1
RF
0.48
=3
R
0.4
00
1
FB
0.32
k
50k
= 10
RFB1 =
0.08
0
k
00
=1
R FB1
0.16
40
=2
1
R FB
0.24
k
=2
1
R FB
ACT4514-003
0.64
0k
68k
k
RFB1 = 12
0
250
500
750
1000
1250
1500
Output Current (mA)
Figure 6:
Frequency Compensation for High RFB1
Figure 7: PCB Layout
Figure 8 and Figure 9 give two typical car charger
application schematics and associated BOM list.
PC Board Layout Guidance
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
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ACT4514
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Rev 1, 21-Jul-11
Figure 8:
Typical Application Circuit for 5V/1.2A Car Charger
Table 2:
BOM List for 5V/1.2A Car Charger
ITEM
REFERENCE
1
U1
IC, ACT4514SH, SOP-8
Active-Semi
1
2
C1
Capacitor, Electrolytic, 47µF/50V, 6.3х7mm
Murata, TDK
1
3
C2
Capacitor, Ceramic, 2.2µF/50V, 1206, SMD
Murata, TDK
1
4
C3
Capacitor, Ceramic, 1.5nF/6.3V, 0603, SMD
Murata, TDK
1
5
C4
Capacitor, Ceramic, 10nF/50V, 0603, SMD
Murata, TDK
1
6
C5
Capacitor, Electrolytic, 100µF/10V, 6.3х7mm
Murata, TDK
1
7
C6
Capacitor, Ceramic, 1µF/10V, 0603, SMD
Murata, TDK
1
8
C7 (Optional)
Capacitor, Ceramic, 220pF/6.3V, 0603
Murata, TDK
1
9
L1
68µH, 1.5A, 20%, SMD CDRH125-680M
Sumida
1
10
D1
Diode, Schottky, 40V/2A, SB240, DO-15
Diodes
1
11
D2
Diode, 75V/150mA, LL4148
Good-ARK
1
12
R1
Chip Resistor, 20kΩ, 0603, 1%
Murata, TDK
1
13
R2
Chip Resistor, 52kΩ, 0603, 1%
Murata, TDK
1
14
R3
Chip Resistor, 12kΩ, 0603, 5%
Murata, TDK
1
15
R4
Chip Resistor, 10kΩ, 0603, 1%
Murata, TDK
1
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DESCRIPTION
- 10 -
MANUFACTURER
QTY
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ACT4514
Active-Semi
Rev 1, 21-Jul-11
Figure 9:
Typical Application Circuit for 5V/0.75A Car Charger
Table 3:
BOM List for 5V/0.75A Car Charger
ITEM REFERENCE
DESCRIPTION
MANUFACTURER
QTY
1
U1
IC, ACT4514SH, SOP-8
Active-Semi
1
2
C1
Capacitor, Electrolytic, 47µF/50V, 6.3х7mm
Murata, TDK
1
3
C2
Capacitor, Ceramic, 2.2µF/50V, 1206, SMD
Murata, TDK
1
4
C3
Capacitor, Ceramic, 1.5nF/6.3V, 0603, SMD
Murata, TDK
1
5
C4
Capacitor, Ceramic, 10nF/50V, 0603, SMD
Murata, TDK
1
6
C5
Capacitor, Electrolytic, 100µF/10V, 6.3х7mm
Murata, TDK
1
7
C6
Capacitor, Ceramic, 1µF/10V, 0603, SMD
Murata, TDK
1
8
C7 (Optional)
Capacitor, Ceramic, 220pF/6.3V, 0603
Murata, TDK
1
9
L1
82µH, 1A, 20%, SMD 1058-MGDN6-00013
Tyco Electronics
1
10
D1
Diode, Schottky, 40V/2A, SB240, DO-15
Diodes
1
11
D2
Diode, 75V/150mA, LL4148
Good-ARK
1
12
R1
Chip Resistor, 33kΩ, 0603, 1%
Murata, TDK
1
13
R2
Chip Resistor, 52kΩ, 0603, 1%
Murata, TDK
1
14
R3
Chip Resistor, 12kΩ, 0603, 5%
Murata, TDK
1
15
R4
Chip Resistor, 10kΩ, 0603, 1%
Murata, TDK
1
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ACT4514
Active-Semi
Rev 1, 21-Jul-11
TYPICAL PERFORMANCE CHARACTERISTICS
(Circuit of Figure 7, IISET = 0.9A, L = 82µH, CIN = 10µF, COUT = 22µF, TA = 25°C, unless otherwise specified.)
Efficiency vs. Load Current
Switching Frequency vs. Input Voltage
Efficiency (%)
80
Switching Frequency (kHz)
VIN = 10V
90
VIN = 12V
70
VIN = 24V
60
50
VOUT = 5V
40
100
10
1000
ACT4514-005
240
ACT4514-004
100
220
200
180
160
140
120
100
10
10000
12
Load Current (mA)
30
32
VIN = 12V
RISET = 33kΩ
900
CC Current (mA)
200
150
100
50
ACT4514-007
1000
ACT4514-006
Switching Frequency (kHz)
24
CC Current vs. Temperature
Switching Frequency vs. Feedback Voltage
250
800
700
600
500
0
0
100
200
300
400
500
600
700
800
400
-40
900
-25
0
25
50
75
80
Temperature (°C)
Feedback Voltage (mV)
Peak Current Limit vs. Duty Cycle
CC Current vs. Input Voltage
900
800
Maximum CC Current (mA)
RISET = 33kΩ
700
600
500
400
ACT4514-009
2500
ACT4514-008
1000
CC Current (mA)
18
Input Voltage (V)
2250
2000
1750
1500
1250
1000
750
500
250
0
10
12
18
24
30
32
0
Input Voltage (V)
Innovative PowerTM
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Duty Cycle
- 12 -
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Copyright © 2011 Active-Semi, Inc.
ACT4514
Active-Semi
Rev 1, 21-Jul-11
TYPICAL PERFORMANCE CHARACTERISTICS CONT’D
(Circuit of Figure 7, IISET = 0.9A, L = 82µH, CIN = 10µF, COUT = 22µF, TA = 25°C, unless otherwise specified.)
Standby Supply Current vs. Input Voltage
Shutdown Current vs. Input Voltage (EN pulled low)
100
Standby Supply Current (µA)
Shutdown Current (µA)
120
80
60
40
20
0
0
5
10
15
20
25
30
35
ACT4514-011
2000
ACT4514-010
140
1800
1600
1400
1200
1000
800
600
400
200
0
40
0
5
Input Voltage (V)
15
20
25
30
35
40
Input Voltage (V)
Start up into CV Load
Reverse Leakage Current (VIN Floating)
80
ACT4514-013
ACT4514-012
100
Reverse Leakage Current (µA)
10
V0UT = 5V
CV = 3.2V
IISET = 0.9A
VIN = 12V
60
CH1
40
20
CH2
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
CH1: IOUT, 500mA/div
CH2: VOUT, 2V/div
TIME: 200µs/div
VOUT (V)
Start up into CV Load
ACT4514-015
ACT4514-014
V0UT = 5V
CV = 3.2V
IISET = 0.9A
VIN = 24V
SW vs. Output Voltage Ripples
VIN = 12V
V0UT = 5V
I0UT = 0.9A
CH1
CH1
CH2
CH2
CH1: IOUT, 500mA/div
CH2: VOUT, 2V/div
TIME: 200µs/div
Innovative PowerTM
CH1: SW, 10V/div
CH2: VOUT_RIPPLE, 50mV/div
TIME: 2µs/div
- 13 -
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Copyright © 2011 Active-Semi, Inc.
ACT4514
Active-Semi
Rev 1, 21-Jul-11
TYPICAL PERFORMANCE CHARACTERISTICS CONT’D
(Circuit of Figure 7, IISET = 0.9A, L = 82µH, CIN = 10µF, COUT = 22µF, TA = 25°C, unless otherwise specified.)
SW vs. Output Voltage Ripples
VIN = 24V
V0UT = 5V
I0UT = 0.9A
ACT4514-017
ACT4514-016
CH1
Start up with EN
VIN = 12V
V0UT = 5V
I0UT = 0.9A
CH1
CH2
CH2
CH1: EN, 1V/div
CH2: VOUT, 1V/div
TIME: 10ms/div
CH1: SW, 10V/div
CH2: VRIPPLE, 50mV/div
TIME: 2µs/div
Load Step Waveforms
Start up with EN
VIN = 12V
V0UT = 5V
IISET = 0.9A
ACT4514-019
VIN = 12V
V0UT = 5V
IISET = 0.9A
ACT4514-021
ACT4514-018
VIN = 24V
V0UT = 5V
IISET = 0.9A
CH1
CH1
CH2
CH2
CH1: IOUT, 500mA/div
CH2: VOUT, 500mV/div
TIME: 100μs/div
CH1: EN, 1V/div
CH2: VOUT, 1V/div
TIME: 10ms/div
Short Circuit
Load Step Waveforms
CH1
ACT4514-020
VIN = 24V
V0UT = 5V
IISET = 0.9A
CH1
CH2
CH2
CH3
CH1: IOUT, 500mA/div
CH2: VOUT, 500mV/div
TIME: 100μs/div
Innovative PowerTM
CH1: VOUT, 2V/div
CH2: IOUT, 1A/div
CH3: SW
TIME: 20µs/div
- 14 -
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Copyright © 2011 Active-Semi, Inc.
ACT4514
Active-Semi
Rev 1, 21-Jul-11
TYPICAL PERFORMANCE CHARACTERISTICS CONT’D
(Circuit of Figure 7, IISET = 0.9A, L = 82µH, CIN = 10µF, COUT = 22µF, TA = 25°C, unless otherwise specified.)
Short Circuit Recovery
Short Circuit
VIN = 12V
V0UT = 5V
IISET = 0.9A
ACT4514-023
CH1
ACT4514-022
VIN = 24V
V0UT = 5V
IISET = 0.9A
CH1
CH2
CH2
CH3
CH3
CH1: VOUT, 2V/div
CH2: IOUT, 1A/div
CH3: SW
TIME: 20µs/div
CH1: VOUT, 2V/div
CH2: IOUT, 1A/div
CH3: SW
TIME: 20µs/div
Short Circuit Recovery
ACT4514-024
VIN = 24V
V0UT = 5V
IISET = 0.9A
CH1
CH2
CH3
CH1: VOUT, 2V/div
CH2: IOUT, 1A/div
CH3: SW
TIME: 20µs/div
Innovative PowerTM
- 15 -
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Copyright © 2011 Active-Semi, Inc.
ACT4514
Active-Semi
Rev 1, 21-Jul-11
PACKAGE OUTLINE
SOP-8 PACKAGE OUTLINE AND DIMENSIONS
D
L
C
E1
E
SYMBOL
?
θ
A
A2
B
A1
e
DIMENSION IN
MILLIMETERS
DIMENSION IN
INCHES
MIN
MAX
MIN
MAX
A
1.350
1.750
0.053
0.069
A1
0.100
0.250
0.004
0.010
A2
1.350
1.550
0.053
0.061
B
0.330
0.510
0.013
0.020
C
0.190
0.250
0.007
0.010
D
4.700
5.100
0.185
0.201
E
3.800
4.000
0.150
0.157
E1
5.800
6.300
0.228
0.248
e
1.270 TYP
0.050 TYP
L
0.400
1.270
0.016
0.050
θ
0°
8°
0°
8°
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
- 16 -
www.active-semi.com
Copyright © 2011 Active-Semi, Inc.