NCP5007/D [ETC]
Compact Backlight LED Boost Driver ; 紧凑型背光LED升压驱动器\n型号: | NCP5007/D |
厂家: | ETC |
描述: | Compact Backlight LED Boost Driver
|
文件: | 总22页 (文件大小:144K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
NCP5007
Compact Backlight LED
Boost Driver
The NCP5007 is a high efficiency boost converter operating in a
current control loop, based on a PFM mode, to drive White LEDs. The
current mode regulation allows a uniform brightness of the LEDs. The
chip has been optimized for small ceramic capacitors and is capable of
supplying up to 1.0 W output power.
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Features
MARKING
DIAGRAM
• Inductor Based Converter brings High Efficiency
• Constant Output Current Regulation
• 2.7 to 5.5 V Input Voltage Range
5
TSOP−5
(SOT23−5, SCR59−5)
SN SUFFIX
5
DCLYW
1
• V to 22 V Output Compliance Allows up to 5 LEDs to be Driven
out
CASE 483
1
in Series which Provides Automatic LED Current Matching
• Built−in Output Overvoltage Protection
• 0.3 mA Standby Quiescent Current
• Includes Dimming Function (PWM)
• Enable Function Driven Directly from Low Battery Voltage Source
• Thermal Shutdown Protection
DCL = Device Code
Y
= Year
W
= Work Week
PIN CONNECTIONS
• All Pins are Fully ESD Protected
• Low EMI Radiation
• Lead−Free Package
FB
1
2
5
4
V
bat
Typical Applications
GND
EN
• LED Display Back Light Control
• High Efficiency Step Up Converter
V
3
out
(Top View)
V
bat
V
bat
U1
EN
ORDERING INFORMATION
C1
3
5
V
bat
Device
Package
Shipping
4.7 mF
NCP5007SNT1G* TSOP−5
*G suffix indicates a Pb−free.
3000 Tape & Reel
GND
L1
22 mH
D1
2
1
4
V
out
GND
GND
FB
MBR0530
C2
1.0 mF
NCP5007
D6
D5
D4
D3
D2
R1
5.6 W
GND
GND
Figure 1. Typical Application
Semiconductor Components Industries, LLC, 2003
1
Publication Order Number:
September, 2003 − Rev. 1
NCP5007/D
NCP5007
Thermal
Shutdown
Current Sense
V
bat
Vsense
V
5
4
bat
V
out
EN
3
100 k
GND
Q1
CONTROLLER
GND
2
−
+
FB
1
300 k
GND
+200 mV
Band Gap
Figure 2. Block Diagram
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2
NCP5007
PIN FUNCTION DESCRIPTION
Pin
Symbol
Type
Description
1
FB
ANALOG
INPUT
This pin provides the output current range adjustment by means of a sense resistor connected
to the analog control or with a PWM control. The dimming function can be achieved by applying
a PWM voltage technique to this pin (see Figure 29). The current output tolerance depends
upon the accuracy of this resistor. Using a "5% metal film resistor, or better, yields good output
current accuracy. Note: A built−in comparator switches OFF the DC/DC converter if the voltage
sensed across this pin and ground is higher than 700 mV typical.
2
3
GND
EN
POWER
This pin is the system ground for the NCP5007 and carries both the power and the analog
signals. High quality ground must be provided to avoid spikes and/or uncontrolled operation.
Care must be observed to avoid high−density current flow in a limited PCB copper track so a
robust ground plane connection is recommended.
DIGITAL
INPUT
This is an Active−High logic input which enables the boost converter. The built−in pulldown
resistor disables the device when the EN pin is left open. Note the logic switching level of this
input has been optimized to allow it to be driven from standard or 1.8 V CMOS logic levels.
The LED brightness can be controlled by applying a pulse width modulated signal to the enable
pin (see Figure 30).
4
V
out
POWER
This pin is the power side of the external inductor and must be connected to the external
Schottky diode. It provides the output current to the load. Since the boost converter operates in
a current loop mode, the output voltage can range up to +22 V but shall not exceed this limit.
However, if the voltage on this pin is higher than the OVP threshold (Over Voltage Protection)
the device enters a shutdown mode. To restart the chip, one must either apply a low to high logic
signal to the EN pin, or switch off the V supply.
bat
A capacitor must be used on V to avoid false triggering of the OVP (Overvoltage Protect)
out
circuit. This capacitor filters the noise created by the fast switching transients. In order to limit
the inrush current and still have acceptable start up time the capacitor value should range
between 1.0 mF and 8.2 mF max. To achieve high efficiency this capacitor should be ceramic
(ESR t 100 mW).
Care must be observed to avoid EMI through the PCB copper tracks connected to this pin.
5
V
bat
POWER
The external voltage supply is connected to this pin. A high quality reservoir capacitor must be
connected across pin 5 and Ground to achieve the specified output voltage parameters. A
4.7 mF/6.3 V, low ESR capacitor must be connected as close as possible across pin 5 and
ground pin 2. The X5R or X7R ceramic MURATA types are recommended.
The return side of the external inductor shall be connected to this pin. Typical application will
use a 22 mH, size 1210, to handle the 10 to 100 mA output current range. When the desired
output current is above 20 mA, the inductor shall have an ESR v1.5 W to achieve good
efficiency over the V range. The output current tolerance can be improved by using a larger
bat
inductor value.
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3
NCP5007
MAXIMUM RATINGS
Rating
Symbol
Value
6.0
Unit
V
Power Supply
V
bat
Output Power Supply Voltage Compliance
V
out
28
V
Digital Input Voltage
Digital Input Current
EN
−0.3 v V v V +0.3
V
mA
in
bat
1.0
ESD Capability (Note 2)
Human Body Model (HBM)
Machine Model (MM)
V
ESD
2.0
200
kV
V
TSOP5 Package
Power Dissipation @ T = +85°C (Note 3)
P
160
250
mW
°C/W
A
D
Thermal Resistance, Junction−to−Air
Operating Ambient Temperature Range
Operating Junction Temperature Range
Maximum Junction Temperature
R
q
JA
T
A
−25 to +85
−25 to +125
+150
°C
°C
°C
°C
T
J
T
Jmax
Storage Temperature Range
T
stg
−65 to +150
1. Maximum Ratings are those values beyond which damage to the device may occur. Exposure to these conditions or conditions beyond those
indicated may adversely affect device reliability. Functional operation under absolute maximum−rated conditions is not implied. Functional
operation should be restricted to the Recommended Operating Conditions.
2. This device series contains ESD protection and exceeds the following tests:
Human Body Model (HBM) "2.0 kV per JEDEC standard: JESD22−A114
Machine Model (MM) "200 V per JEDEC standard: JESD22−A115
3. The maximum package power dissipation limit must not be exceeded.
4. Latch−up current maximum rating: "100 mA per JEDEC standard: JESD78.
5. Moisture Sensivity Level (MSL): 1 per IPC/JEDEC standard: J−STD−020A.
POWER SUPPLY SECTION (Typical values are referenced to T = +25°C, Min & Max values are referenced −25°C to +85°C ambient
a
temperature, unless otherwise noted.)
Rating
Pin
4
Symbol
Min
2.7
22
Typ
−
Max
5.5
−
Unit
V
Power Supply
V
bat
Output Load Voltage Compliance
Continuous DC Current in the Load
5
V
24.5
−
V
out
out
5
I
50
−
mA
@ V = 3 LED, L = 22 mH, ESR < 1.5 W, V = 3.6 V
out
bat
Standby Current @ I = 0 mA, EN = L, V = 3.6 V
4
I
−
0.45
−
mA
out
bat
stdb
Standby Current @ I = 0 mA, EN = L, V = 5.5 V
4
4
I
−
−
1.0
3.0
−
mA
out
bat
stdb
Inductor Discharging Time @ V = 3.6 V, L = 22 mH, 3 LED,
Toffmax
320
ns
bat
I
= 10 mA
out
Thermal Shutdown Protection
−
−
T
−
−
160
30
−
−
°C
°C
SD
Thermal Shutdown Protection Hysteresis
T
SDH
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4
NCP5007
ANALOG SECTION (Typical values are referenced to T = +25°C, Min & Max values are referenced −25°C to +85°C ambient
a
temperature, unless otherwise noted.)
Rating
Pin
Symbol
Min
Typ
Max
Unit
High Level Input Voltage
Low Level Input Voltage
1
EN
1.3
−
−
−
−
0.4
V
EN Pull Down Resistor
1
4
5
R
−
170
−
100
200
100
−
230
−
kW
mV
ms
EN
Feedback Voltage Threshold
FB
Output Current Stabilizes @ 5% time delay following a DC/DC
I
outdly
start−up @ V = 3.6 V, L = 22 mH, I = 20 mA
bat
out
Internal Switch ON Resistor @ T
= +25°C
5
QR
−
1.7
−
W
amb
DSON
6. The overall tolerance depends upon the accuracy of the external resistor.
THEORY OF OPERATION
The DC/DC converter is designed to supply a constant
current to the external load, the circuit being powered from
a standard battery supply. Since the regulation is made by
means of a current loop, the output voltage will vary
depending upon the dynamic impedance presented by the
load.
Considering a high intensity LED, the output voltage can
range from a low of 6.4 V (two LED in series biased with a
low current), up to 22 V, the maximum the chip can sustain
continuously. The basic DC/DC structure is depicted in
Figure 3.
With a 22 V operating voltage capability, the power
device Q1 can accommodate a high voltage source without
any leakage current degradation.
V
bat
L1
22 mH
Vdsense
POR
4
D1
Vds
Q1
TIME_OUT
ZERO_CROSSING
GND
RESET
LOGIC
CONTROL
Vdsense
GND
+
R1
−
1
V(Ipeak)
−
+
R2
xR
C2
Vs
Vref
GND
GND
Figure 3. Basic DC/DC Converter Structure
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5
NCP5007
Basically, the chip operates with two cycles:
flip−flop resets, the NMOS is deactivated and the current is
dumped into the load. Since the timing is application
dependent, the internal timer limits the Toff cycle to 320 ns
(typical), making sure the system operates in a continuous
mode to maximize the energy transfer.
Cycle #1 : time t1, the energy is stored into the inductor
Cycle #2 : time t2, the energy is dumped to the load
The POR signal sets the flip−flop and the first cycle takes
place. When the current hits the peak value, defined by the
error amplifier associated with the loop regulation, the
First Start−Up
Normal Operation
Ipeak
I
L
Iv
t1
t2
0 mA
t
t
t
Ids
0 mA
Io
0 mA
Figure 4. Basic DC/DC Operation
Based on the data sheet, the current flowing into the
inductor is bounded by two limits:
• Ipeak Value: Internally fixed to 350 mA typical
• Iv Value: Limited by the fixed Toff time built in the
chip (320 ns typical)
The system operates in a continuous mode as depicted in
Of course, from a practical stand point, the inductor must
be sized to cope with the peak current present in the circuit
to avoid saturation of the core. On top of that, the ferrite
material shall be capable to operate at high frequency
(1.0 MHz) to minimize the Foucault’s losses developed
during the cycles.
The operating frequency can be derived from the
Figure 4 and t & t times can be derived from basic
1
2
electrical parameters. Let V = Vo − V , rearranging
bat
equations. (Note: The equations are for theoretical analysis
only, they do not include the losses.)
Equation 1:
dI * L
E
di
dt
(eq. 5)
ton +
(eq. 1)
E + L *
Since toff is nearly constant (according to the 320 ns
typical time), the dI is constant for a given load and
inductance value. Rearranging Equation 5 yields:
Let E = V , then:
bat
(Ip * Iv) * L
(eq. 2)
(eq. 3)
t1 +
t2 +
Vbat
V*dt * L
L
(Ip * Iv) * L
Vo * Vbat
(eq. 6)
ton +
E
Let E = V , and Vopk = output peak voltage, then:
bat
Since t = 320 ns typical and Vo = 22 V maximum, then
2
(assuming a typical V = 3.0 V):
(Vopk * Vbat) * dt
bat
(eq. 7)
ton +
Vbat
t2 * (Vo * Vbat)
DI +
Finally, the operating frequency is:
L
(eq. 4)
1
(eq. 8)
F +
* 9
320e
* (22 * 3.0)
* 6
ton ) toff
DImax +
+ 276 mA
22e
The output power supplied by the NCP5007 is limited to
one watt: Figure 5 shows the maximum power that can be
delivered by the chip as a function of the input voltage.
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NCP5007
1200
400
3 LED
L = 22µH
= 10W
T = +25°C
A
R
1000
800
sense
350
300
2 LED
4 LED
5 LED
600
250
200
400
200
0
P
out
= f(V ) @ R
= 2.0 W
bat
sense
150
6
2
3
4
5
2
3
4
5
6
V
bat
(V)
V
bat
(V)
Test conditions: 5 LEDs in series, steady state operation
Figure 5. Maximum Output Power as a Function of
the Battery Supply Voltage
Figure 6. Typical Inductor Peak Current as a
Function of Vbat Voltage
120
100
2 LED
3 LED
80
60
40
20
0
4 LED
5 LED
2.5
3.0
3.5
4.0
(V)
4.5
5.0
5.5
V
bat
Test conditions: L = 22 mH, Rsense = 2.0 W, Tamb = +25°C
Figure 7. Maximum Output Current as a Function of Vbat
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7
NCP5007
Output Current Range Set−Up
The current regulation is achieved by means of an external sense resistor connected in series with the LED string.
V
bat
L1
22 mH
V
out
D1
4
FB
1
Q1
CONTROLLER
GND
R1
xW
GND
Figure 8. Output Current Feedback
Feedback Threshold
200 mV
10 mA
The current flowing through the LED creates a voltage
drop across the sense resistor R1. The voltage drop is
constantly monitored internally, and maximum peak current
allowed in the inductor is set accordingly in order to keep
constant this voltage drop (and thus the current flowing
through the LED). For example, should one need a 10 mA
output current, the sense resistor should be sized according
to the following equation:
(eq. 9)
R
+
+
+ 20 W
1
I
out
A standard 5% tolerance resistor, 22 W SMD device,
yields 9.09 mA, good enough to fulfill the back light
demand. The typical application schematic diagram is
provided in Figure 9.
V
bat
U1
3
C1
5
4
Pulse
EN
V
bat
4.7 mF
GND
L1
22 mH
D1
2
1
V
out
GND
GND
FB
MBR0530
C2
1.0 mF
NCP5007
D6
D5
D4
D3
D2
R1
GND
GND
22 W
LED
LED
LED
LED
LED
Figure 9. Basic Schematic Diagram
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NCP5007
Output Load Drive
The Schottky diode D1, associated with capacitor C2 (see
Figure 9), provides a rectification and filtering function.
When a pulse−operating mode is required:
• A PWM mode control can be used to adjust the output
current range by means of a resistor and a capacitor
connected across FB pin. On the other hand, the
Schottky diode can be removed and replaced by at least
one LED diode, keeping in mind such LED shall
sustain the large pulsed peak current during the
operation.
In order to take advantage of the built−in Boost
capabilities, one shall operate the NCP5007 in the
continuous output current mode. Such a mode is achieved by
using and external reservoir capacitor (see Table 1) across
the LED.
At this point, the peak current flowing into the LED diodes
shall be within the maximum ratings specified for these
devices. Of course, pulsed operation can be achieved, thanks
to the EN signal pin 3, to force high current into the LED
when necessary.
TYPICAL OPERATING CHARACTERISTICS
100
100
90
4 LED/10 mA
4 LED/4 mA
90
80
80
5 LED/4 mA
70
5 LED/10 mA
70
60
50
40
30
2 LED/10 mA
3 LED/10 mA
3 LED/4 mA
2 LED/4 mA
60
50
40
30
20
10
0
20
10
0
2.50
3.00
3.50
4.00
Vbat (V)
4.50
5.00
5.50
2.50
3.00
3.50
4.00
4.50
5.00
5.50
Vbat (V)
Figure 10. Overall Efficiency vs. Power Supply −
Figure 11. Overall Efficiency vs. Power Supply −
Iout = 4.0 mA, L = 22 mH
Iout = 10 mA, L = 22 mH
100
90
100
90
3 LED/15 mA
3 LED/20 mA
80
80
70
60
50
40
30
20
10
0
70
60
50
40
30
20
10
0
5 LED/20 mA
5 LED/15 mA
2 LED/15 mA
4 LED/15 mA
2 LED/20 mA
4 LED/20 mA
2.50
3.00
3.50
4.00
4.50
5.50
2.50
3.00
3.50
4.00
4.50
5.00
5.50
5.00
Vbat (V)
Vbat (V)
Figure 12. Overall Efficiency vs. Power Supply −
Figure 13. Overall Efficiency vs. Power Supply −
Iout = 15 mA, L = 22 mH
Iout = 20 mA, L = 22 mH
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NCP5007
TYPICAL OPERATING CHARACTERISTICS
(All curve conditions: L = 22 mH, Cin = 4.7 mF, C = 1.0 mF, Typical curve @ T = +25°C)
out
a
100
90
80
70
60
50
40
30
20
10
0
30
25
20
2 LED/40 mA
3 LED/40 mA
I
= 20 mA Nom
OUT
5 LED/40 mA
4 LED/40 mA
15
10
5
I
= 10 mA Nom
OUT
L = 22 mH
T = 25°C
A
0
2.5
3.0
3.5
4.0
(V)
4.5
5.0
5.5
2.50
3.00
3.50
4.00
(V)
4.50
5.00
5.50
V
bat
V
BAT
Figure 14. Overall Efficiency vs. Power Supply −
Figure 15. Current Variation vs. Power Supply with
3 Series LED’s
Iout = 40 mA, L = 22 mH
25
20
15
10
25
20
15
10
I
= 20 mA Nom
I
= 20 mA Nom
OUT
OUT
I
= 10 mA Nom
I
= 10 mA Nom
OUT
OUT
5
0
5
0
L = 22 mH
T = 25°C
A
L = 22 mH
T = 25°C
A
2.5
3.0
3.5
4.0
(V)
4.5
5.0
5.5
2.5
3.0
3.5
4.0
(V)
4.5
5.0
5.5
V
V
BAT
BAT
Figure 16. Current Variation vs. Power Supply with
4 Series LED’s
Figure 17. Current Variation vs. Power Supply with
5 Series LED’s
205
5
4
3
2
204
203
202
201
200
199
198
197
V
bat
= 3.1 V thru 5.5 V
1
0
V
bat
= 3.1V thru 5.5V
−1
−2
−3
196
195
−40
−4
−5
−40
−20
0
20
40
60
80
100
−20
0
20
40
60
80
100
TEMPERATURE (°C)
TEMPERATURE (°C)
Figure 18. Feedback Voltage Stability
Figure 19. Feedback Voltage Variation
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10
NCP5007
TYPICAL OPERATING CHARACTERISTICS
(All curve conditions: L = 22 mH, Cin = 4.7 mF, C = 1.0 mF, Typical curve @ T = +25°C)
out
a
2.5
2.0
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
−40°C thru 125°C
2 LED
1.5
1.0
0.5
0
3 LED
4 LED
5 LED
2.7
3.3
3.9
4.5
5.1
5.5
2.5
3.0
3.5
4.0
(V)
4.5
5.0
5.5
V
bat
, BATTERY VOLTAGE (V)
V
bat
Figure 20. Standby Current
Figure 21. Typical Operating Frequency
26
V
bat
= 3.6V
V
V
= 2.7V
25
bat
= 5.5V
bat
24
23
22
−40 −20
0
20
40
60
80
100 120130
TEMPERATURE(°C)
Figure 22. Overvoltage Protection
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NCP5007
TYPICAL OPERATING WAVEFORMS
V
out
Inductor
Current
Conditions: V = 3.6 V, L = 22 mH, 5 LED, I = 15 mA
bat
out
out
Figure 23. Typical Power Up Response
V
out
Inductor
Current
Conditions: V = 3.6 V, L = 22 mH, 5 LED, I = 15 mA
bat
out
out
Figure 24. Typical Start Up Inductor Current and Output Voltage
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NCP5007
TYPICAL OPERATING WAVEFORMS
Inductor
Current
Conditions: V = 3.6 V, L = 22 mH, 5 LED, I = 15 mA
bat
out
out
Figure 25. Typical Inductor Current
V
out
Ripple
50 mV/div
Inductor
Current
Conditions: V = 3.6 V, L = 22 mH, 5 LED, I = 15 mA
bat
out
out
Figure 26. Typical Output Voltage Ripple
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13
NCP5007
TYPICAL OPERATING WAVEFORMS
Output Voltage
Inductor Current
Test Conditions: L = 22 mH, I = 15 mA, V = 3.6 V, Ambient Temperature, LED = 5
out
bat
Figure 27. Typical Output Peak Voltage
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14
NCP5007
TYPICAL APPLICATIONS CIRCUITS
Standard Feedback
The standard feedback provides constant current to the
LEDs, independently of the V supply and number of
LEDs in series. Figure 28 depicts a typical application to
supply 13 mA to the load.
bat
V
bat
V
bat
U1
EN
C1
3
5
4
V
bat
4.7 mF
L1
22 mH
GND
D1
2
1
GND
FB
GND
V
out
MBR0530
NCP5007
C2
1.0 mF
R1
D6
D5
D4
D3
D2
GND
GND
15 W
LED LED LED
LED
LED
Figure 28. Basic DC Current Mode Operation with
Analog Feedback
PWM Operation
Although the pulsed mode will provide a good dimming
function, it will yield high switching transients which are
difficult to filter out in the control loop. As such this first
approach is not recommended. The output current depends
upon the duty cycle of the signal presented to the node pin 1:
this is very similar to the digital control shown in Figure 30.
The average mode yields a noise−free operation since the
converter operates continuously, together with a very good
dimming function. The cost is an extra resistor and one extra
capacitor, both being low cost parts.
The analog feedback pin 1 provides a way to dim the LED
by means of an external PWM signal as depicted in
Figure 29. Taking advantage of the high internal impedance
presented by the FB pin, one can set up a simple R/C network
to accommodate such a dimming function. Two modes of
operation can be considered:
• Pulsed mode, with no filtering
• Averaged mode with filtering capacitor
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15
NCP5007
V
bat
V
bat
U1
EN
C1
3
5
4
V
bat
4.7 mF
L1
22 mH
Average Network
R2
D1
GND
2
1
GND
FB
GND
V
out
R3
PWM
MBR0530
10 k
150 k
NCP5007
C2
1.0 mF
C3
100 nF
R4
5.6 k
GND
GND
GND
R1
10 W
D6
D5
D4
D3
D2
LED LED LED
Sense Resistor
LED
LED
NOTE: RC filter R2 and C3 is optional (see text)
Figure 29. Basic DC Current Mode Operation with PWM Control
To implement such a function, lets consider the feedback
input as an operational amplifier with a high impedance input
(reference schematic Figure 29). The analog loop will keep
going to balance the current flowing through the sense
resistor R1 until the feedback voltage is 200 mV. An extra
resistor (R4) isolates the FB node from low resistance to
ground, making possible to add an external voltage to this pin.
The time constant R2/C3 generates the voltage across C3,
added to the node pin 1, while R2/R3/R4/R1/C3 create the
discharge time constant. In order to minimize the pick up
noise at FB node, the resistors shall have relative medium
value, preferably well below 1.0 MW. Consequently, let
R2 = 150 k, R3 = 10 k and R4 = 5.6 k. In addition, the
feedback delay to control the luminosity of the LED shall be
acceptable by the user, 10 ms or less being a good
compromise. The time constant can now be calculated based
on a 400 mV offset voltage at the C3/R2/R3 node to force
zero current to the LED. Assuming the PWM signal comes
from a standard gate powered by a 3.0 V supply, running at
5.0 kHz, then full dimming of the LED can be achieved with
a 95% span of the Duty Cycle signal.
Digital Control
An alternative method of controlling the luminosity of the
LEDs is to apply a PWM signal to the EN pin (see
Figure 30). The output current depends upon the Duty
Cycle, but care must be observed as the DC/DC converter is
continuously pulsed ON/OFF and noise is likely to be
generated.
V
bat
U1
3
C1
5
4
Pulse
EN
V
bat
4.7 mF
L1
22 mH
GND
D1
2
1
GND
FB
GND
V
out
MBR0530
NCP5007
C2
1.0 mF
R1
5.6 W
D6
D5
D4
D3
D2
GND
GND
NOTE: Pulse width and frequency depends upon the application constraints.
Figure 30. Typical Semi−Pulsed Mode of Operation
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NCP5007
Typical LEDs Load Mapping
Since the output power is battery limited (see Figure 5),
one can arrange the LEDs in a variety of different
configurations. Powering ten LEDs can be achieved by a
series/parallel combination as depicted in Figure 31.
50 mA
75 mA
Load
Load
D1
LED
D5
LED
D1
LED
D3
LED
D5
LED
D7
LED
D9
LED
D2
LED
D6
LED
D2
LED
D4
LED
D6
LED
D8
LED
D10
LED
D3
LED
D7
LED
Sense
Resistor
R1
2.7 W
D4
LED
D8
LED
GND
60 mA
Load
Sense
R1
D1
LED
D4
LED
D7
LED
D10
LED
D13
LED
3.9 W
Resistor
GND
D2
LED
D5
LED
D8
LED
D11
LED
D14
LED
D3
LED
D6
LED
D9
LED
D12
LED
D15
LED
Test conditions:
V
L
C
= 3.6 V
= 22 mH
= 1.0 mF
bat
out
out
Sense
Resistor
R1
3.3 W
GND
Figure 31. Examples of Possible LED Arrangements
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17
NCP5007
ON Semiconductor provides a demo board to evaluate the performance of the NCP5007. The schematic for that demo board
is illustrated in Figure 32.
TP3
V
bat
V
bat
C1
V
bat
S2
S1
4.7 mF/10 V
3
2
1
GND
SELECT
MANUAL
JP1
ISense
U1
EN
GND
R3
3
5
V
bat
3
2
1
TP1
V
out
L1
22 mH
10 k
2
1
GND
GND
D1
S3
V
out
4
3
2
1
R2
R5
0 R
MBR0530
BRIGHTNESS
FB
C3
GND
10 k
NCP5007
MODULATION
Jumper = 0 W
R1
TP2
FB
J3
150 k
GND
R4
C2
100 nF
5.6 k
V
bat
J2
2
1
D6
D5
D4
D3
LED
D2
R10
10 R
Z1
GND
PWR
J1
LED LED LED
LED
GND
V
bat
1
2
Figure 32. NCP5007 Demo Board Schematic Diagram
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18
NCP5007
Table 1. Recommended External Parts
Part
Manufacturer
Description
Part Number
MBR0530T1
30 V Low Vf Schottky Diode
20 V Low Vf Schottky Diode
20 V Low Vf Schottky Diode
Ceramic Cap. 1.0 mF/16 V
Ceramic Cap. 4.7 mF/6.3 V
Inductor 22 mH
ON Semiconductor
ON Semiconductor
ON Semiconductor
MURATA
SOD−123 (1.6 x 3.2 mm)
SOD−323 (1.25 x 2.5 mm)
SOD−563 (1.6 x 1.6 mm)
GRM42−X7R
NSR0320MW2T1
NSR0320XV6T1
GRM42−6X7R−105K16
GRM40−X5R−475K6.3
1008PS−223MC
MURATA
GRM40−X5R
CoilCraft
1008PS−Shielded
Power Wafer
Inductor 22 mH
CoilCraft
LPQ4812−223KXC
Figure 33. NCP5007 Demo Board PCB: Top Layer
Figure 34. NCP5007 Demo Board Top Silkscreen
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NCP5007
FIGURES INDEX
Figure 1: Typical Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 2: Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Figure 3: Basic DC/DC Converter Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Figure 4: Basic DC/DC Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Figure 5: Maximum Output Power as a Function of the Battery Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Figure 6: Typical Inductor Peak Current as a Function of V Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
bat
Figure 7: Maximum Output Current as a Function of V
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
bat
Figure 8: Output Current Feedback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 9: Basic Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 10: Overall Efficiency vs. Power Supply − I = 4.0 mA, L = 22 mH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
out
Figure 11: Overall Efficiency vs. Power Supply − I = 10 mA, L = 22 mH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
out
Figure 12: Overall Efficiency vs. Power Supply − I = 15 mA, L = 22 mH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
out
Figure 13: Overall Efficiency vs. Power Supply − I = 20 mA, L = 22 mH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
out
Figure 14: Overall Efficiency vs. Power Supply − I = 40 mA, L = 22 mH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
out
Figure 15: Feedback Voltage Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 16: Feedback Voltage Variation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 17: Standby Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 18: Typical Operating Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 19: Overvoltage Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Figure 23: Typical Power Up Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 24: Typical Start Up Inductor Current and Output Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Figure 25: Typical Inductor Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 26: Typical Output Voltage Ripple . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 27: Typical Output Peak Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 28: Basic DC Current Mode Operation with Analog Feedback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 29: Basic DC Current Mode Operation with PWM Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 30: Typical Semi−Pulsed Mode of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 31: Examples of Possible LED Arrangements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 32: NCP5007 Demo Board Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Figure 33: NCP5007 Demo Board PCB: Top Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 34: NCP5007 Demo Board Top Silkscreen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
NOTE CAPTIONS INDEX
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Maximum Ratings are those values beyond which damage to the device may occur . . . . . . . . . . . . . . . . . . . . 4
This device series contains ESD protection and exceeds the following tests . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
The maximum package power dissipation limit must not be exceeded . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Latch−up current maximum rating: "100 mA per JEDEC standard: JESD78 . . . . . . . . . . . . . . . . . . . . . . . . . 4
Moisture Sensivity Level (MSL): 1 per IPC/JEDEC standard: J−STD−020A . . . . . . . . . . . . . . . . . . . . . . . . . . 4
The overall tolerance depends upon the accuracy of the external resistor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
ABBREVIATIONS
EN
Enable
FB
Feed Back
POR
Power On Reset: Internal pulse to reset the chip when the power supply is applied
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20
NCP5007
PACKAGE DIMENSIONS
TSOP−5
SN SUFFIX
CASE 483−02
ISSUE C
NOTES:
1. DIMENSIONING AND TOLERANCING PER
ANSI Y14.5M, 1982.
2. CONTROLLING DIMENSION: MILLIMETER.
3. MAXIMUM LEAD THICKNESS INCLUDES
LEAD FINISH THICKNESS. MINIMUM LEAD
THICKNESS IS THE MINIMUM THICKNESS
OF BASE MATERIAL.
4. A AND B DIMENSIONS DO NOT INCLUDE
MOLD FLASH, PROTRUSIONS, OR GATE
BURRS.
D
5
4
3
B
C
S
1
2
L
MILLIMETERS
DIM MIN MAX
INCHES
MIN MAX
G
A
B
C
D
G
H
J
K
L
M
S
2.90
1.30
0.90
0.25
0.85
3.10 0.1142 0.1220
1.70 0.0512 0.0669
1.10 0.0354 0.0433
0.50 0.0098 0.0197
1.05 0.0335 0.0413
A
J
0.013 0.100 0.0005 0.0040
0.05 (0.002)
0.10
0.20
1.25
0
0.26 0.0040 0.0102
0.60 0.0079 0.0236
1.55 0.0493 0.0610
H
M
K
10
0
10
_
_
_
_
2.50
3.00 0.0985 0.1181
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21
NCP5007
ON Semiconductor and
are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice
to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages.
“Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All
operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights
nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should
Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates,
and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death
associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal
Opportunity/Affirmative Action Employer. This literature is subject to all applicable copyright laws and is not for resale in any manner.
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LITERATURE FULFILLMENT:
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For additional information, please contact your
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NCP5007/D
相关型号:
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