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NCP1450A
Technical data
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Technical data
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ON Semiconductor NCP1450A Technical data

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NCP1450A
PWM Step−up DC−DC Controller
The NCP1450A series are PWM step−up DC−DC switching controller that are specially designed for powering portable equipment from one or two cells battery packs. The NCP1450A series have a driver pin, EXT pin, for connecting to an external transistor. Large output currents can be obtained by connecting a low ON−resistance external power transistor to the EXT pin. The device will automatically skip switching cycles under light load condition to maintain high efficiency at light loads. With only six external components, this series allows a simple means to implement highly efficient converter for large output current applications.
Each device consists of an on−chip Pulse Width Modulation (PWM) oscillator, PWM controller, phase−compensated error amplifier, soft−start, voltage reference, and driver for driving external power transistor. Additionally, a chip enable feature is provided to power down the converter for extended battery life.
The NCP1450A device series are available in the TSOP−5 package with five standard regulated output voltages. Additional voltages that range from 1.8 V to 5.0 V in 100 mV steps can be manufactured.
Features
• High Efficiency 86% at I
88% at I
• Low Startup Voltage of 0.9 V typical at I
• Operation Down to 0.6 V
• Five Standard Voltages: 1.9 V, 2.7 V, 3.0 V, 3.3 V, 5.0 V with High
Accuracy ± 2.5%
• Low Conversion Ripple
• High Output Current up to 1000 mA
(3.0 V version at V
• Fixed Frequency Pulse Width Modulation (PWM) at 180 kHz
• Chip Enable Pin with On−chip 150 nA Pullup Current Source
• Low Profile and Micro Miniature TSOP−5 Package
• Pb−Free Packages are Available
= 200 mA, VIN = 2.0 V, V
O
= 400 mA, VIN = 3.0 V, V
O
= 2.0 V, L = 10 H, C
IN
= 1.0 mA
O
OUT
OUT OUT
= 220 F)
= 3.0 V = 5.0 V
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5
1
TSOP−5
SN SUFFIX
CASE 483
MARKING DIAGRAM AND
PIN CONNECTIONS
1
CE
G
2
OUT
3
NC
(Top View)
xxx =Specific Device Marking A = Assembly Location Y = Year W = Work Week G = Pb−Free Package (Note: Microdot may be in either location)
ORDERING INFORMATION
See detailed ordering and shipping information in the ordering information section on page 3 of this data sheet.
5
xxxAYWG
EXT
GND
4
Typical Applications
• Personal Digital Assistant (PDA)
• Electronic Games
• Portable Audio (MP3)
• Digital Still Cameras
• Handheld Instruments
© Semiconductor Components Industries, LLC, 2005
December, 2005 − Rev. 7
1 Publication Order Number:
NCP1450A/D
NCP1450A
Á
Á
Á
OUT
NC
GND
V
IN
CE
1
EXT
5
V
OUT
OUT
2
NC
3
GND
NCP1450A
4
Figure 1. Typical Step−up Converter Application
2
Error
Amplifier
+
−
3
Phase
Compensation
Voltage
Reference
Soft−Start
PWM
Controller
180 kHz
Oscillator
Driver
4
EXT 5
PIN FUNCTION DESCRIPTION
Pin # Symbol Pin Description
ÁÁÁ
1
2 3 4 5
CE
ÁÁÁÁ
OUT
NC
GND
EXT
1 CE
Figure 2. Representative Block Diagram
Chip Enable Pin (1) The chip is enabled if a voltage equal to or greater than 0.9 V is applied. (2) The chip is disabled if a voltage less than 0.3 V is applied.
ББББББББББББББББББББББ
(3) The chip is enabled if this pin is left floating. Output voltage monitor pin and also the power supply pin for the device. No internal connection to this pin. Ground pin. External transistor drive pin.
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2
NCP1450A
Á
Á
Á
Á
Á
Á
Á
Á
Á
Á
Á
Á
Á
Á
Á
Á
ORDERING INFORMATION (Note 1)
Output
Device
Voltage
NCP1450ASN19T1
NCP1450ASN19T1G
1.9 V
NCP1450ASN27T1G
NCP1450ASN27T1
2.7 V DAZ
NCP1450ASN30T1
NCP1450ASN30T1G
3.0 V DBA
NCP1450ASN33T1
NCP1450ASN33T1G
3.3 V DBC
NCP1450ASN50T1
NCP1450ASN50T1G
5.0 V DBD
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D.
1. The ordering information lists five standard output voltage device options. Additional devices with output voltage ranging from
1.8 V to 5.0 V in 100 mV increments can be manufactured. Contact your ON Semiconductor representative for availability.
Switching
Frequency
180 KHz
Marking Package Shipping
TSOP−5
DAY
TSOP−5
(Pb−Free)
TSOP−5 TSOP−5
(Pb−Free)
TSOP−5 TSOP−5
(Pb−Free)
3000 Units
on 7 Inch Reel
TSOP−5 TSOP−5
(Pb−Free)
TSOP−5 TSOP−5
(Pb−Free)
†
MAXIMUM RATINGS
Rating Symbol Value Unit
Power Supply Voltage (Pin 2) Input/Output Pins
EXT (Pin 5)
ББББББББББББББББББ
EXT Sink/Source Current
CE (Pin 1)
Input Voltage Range
ББББББББББББББББББ
Input Current Range
Power Dissipation and Thermal Characteristics
ББББББББББББББББББ
Maximum Power Dissipation @ T Thermal Resistance Junction−to−Air
ББББББББББББББББББ
= 25°C
A
Operating Ambient Temperature Range Operating Junction Temperature Range Storage Temperature Range
Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit values (not normal operating conditions) and are not valid simultaneously . If these limits are exceeded, device functional operation is not implied, damage may occur and reliability may be affected.
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. Latchup Current Maximum Rating: $150 mA per JEDEC standard: JESD78.
4. Moisture Sensitivity Level (MSL): 1 per IPC/JEDEC standard: J−STD−020A.
V
OUT
V
EXT
ÁÁÁ
I
EXT
V
CE
ÁÁÁ
I
CE
ÁÁÁ
P
D
R
JA
ÁÁÁ
T
A
T
J
T
stg
6.0
−0.3 to 6.0
БББББ
−150 to 150
−0.3 to 6.0
БББББ
−150 to 150
БББББ
БББББ
500 250
−40 to +85
−40 to +150
−55 to +150
V
V
ÁÁ
mA
V
ÁÁ
mA
ÁÁ
mW
°C/W
ÁÁ
°C °C °C
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3
NCP1450A
ELECTRICAL CHARACTERISTICS (For all values T
= 25°C, unless otherwise noted.)
A
Characteristic
OSCILLATOR
Frequency (V
OUT
= V
0.96, Note 5) f
SET
Frequency Temperature Coefficient (TA = −40°C to 85°C) Maximum PWM Duty Cycle (V
OUT
= V
0.96) D
SET
Minimum Startup Voltage (IO = 0 mA) V Minimum Startup Voltage Temperature Coefficient (TA = −40°C to 85°C) Minimum Operation Hold Voltage (IO = 0 mA) V Soft−Start Time (V
OUT
= V
Note 6) t
SET,
CE (PIN 1)
CE Input Voltage (V
OUT
= V
SET
0.96) High State, Device Enabled Low State, Device Disabled
CE Input Current (Note 6)
High State, Device Enabled (V Low State, Device Disabled (V
= VCE = 5.0 V)
OUT
= 5.0 V, VCE = 0 V)
OUT
EXT (PIN 5)
EXT “H” Output Current (V
EXT
= V
OUT
−0.4 V)
Device Suffix:
19T1 27T1 30T1 33T1 50T1
EXT “L” Output Current(V
EXT
= 0.4 V)
Device Suffix:
19T1 27T1 30T1 33T1 50T1
TOTAL DEVICE
Output Voltage
Device Suffix:
19T1 27T1 30T1 33T1
50T1 Output Voltage Temperature Coefficient (TA = −40 to +85°C) Operating Current (V
= VCE = V
OUT
0.96, Note 5)
SET
Device Suffix:
19T1
27T1
30T1
33T1
50T1 Standby Current (V Off−State Current (V
5. V
means setting of output voltage.
SET
6. This parameter is guaranteed by design.
= VCE = V
OUT
= 5.0 V, VCE = 0 V, TA = −40 to +85°C, Note 7) I
OUT
+0.5 V) I
SET
7. CE pin is integrated with an internal 150 nA pullup current source.
Symbol Min Typ Max Unit
144 180 216 kHz
− 0.11 − %/°C
70 80 90 %
− 0.8 0.9 V
− −1.6 − mV/°C
− 0.6 0.7 V
− 100 250 ms
V
OSC
f
MAX
start
start
hold
SS
V
V
CE(high)
V
CE(low)
0.9
−
−
−
−
0.3 A
I
CE(high)
I
CE(low)
I
EXTH
I
EXTL
V
OUT
V
OUT
I
DD
STB OFF
−0.5 0
−
−
−
−
−
20.0
30.0
30.0
30.0
35.0
1.853
2.633
2.925
3.218
4.875
0
0.15
−25.0
−35.0
−37.7
−40.0
−53.7
38.3
48.0
50.8
52.0
58.2
1.9
2.7
3.0
3.3
5.0
0.5
0.5
−20.0
−30.0
−30.0
−30.0
−35.0
−
−
−
−
−
1.948
2.768
3.075
3.383
5.125
− 150 − ppm/°C
−
−
−
−
−
55 93
98 103 136
90 140 150 160 220
− 15 20
− 0.6 1.5
mA
mA
V
A
AA
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NCP1450A
V
, OUTPUT VOLTAGE (V)
EFFICIENCY (%)
0
0
0
2.1
2.0
1.9 V
= 0.9 V V
IN
= 1.2 V V
IN
IN
= 1.5 V
1.8
NCP1450ASN19T1
, OUTPUT VOLTAGE (V)
1.7
OUT
V
1.6
0
400200
L = 10 H Q = NTGS3446T1
= 220 F
C
OUT
T
= 25°C
A
600
800 1000
IO, OUTPUT CURRENT (mA)
Figure 3. NCP1450ASN19T1 Output Voltage
vs. Output Current
5.2
V
= 4.5 V
5.1
V
= 1.2 V
IN
V
= 2.0 V
IN
V
IN
= 4.0 V
IN
5.0
V
= 1.5 V
IN
V
= 2.5 V
IN
V
= 3.0 V
IN
4.9
NCP1450ASN50T1 L = 10 H Q = NTGS3446T1 C
= 220 F
OUT
T
= 25°C
A
OUT
4.8
4.7
V
= 0.9 V
IN
0 600400200 800 1000
IO, OUTPUT CURRENT (mA)
Figure 5. NCP1450ASN50T1 Output Voltage
vs. Output Current
100
V
= 2.0 V
IN
80
V
IN
= 1.5 V
60
40
20
0
0.01 1001010.1 1000
V
= 0.9 V
IN
V
= 1.2 V
IN
IO, OUTPUT CURRENT (mA)
V
= 2.5 V
IN
NCP1450ASN30T1 L = 10 H Q = NTGS3446T1 C
= 220 F
OUT
T
= 25°C
A
3.2
3.1 V
IN
3.0
V
= 0.9 V V
IN
2.9
NCP1450ASN30T1
, OUTPUT VOLTAGE (V) V
L = 10 H Q = NTGS3446T1
2.8
OUT
2.7
= 220 F
C
OUT
T
= 25°C
A
0 600400200 800 100
= 1.2 V
IN
V
= 1.5 V
IN
V
IN
IO, OUTPUT CURRENT (mA)
Figure 4. NCP1450ASN30T1 Output Voltage
vs. Output Current
100
V
= 1.5 V
IN
80
V
= 1.2 V
IN
60
V
= 0.9 V
IN
40
EFFICIENCY (%)
20
0
NCP1450ASN19T1 L = 10 H Q = NTGS3446T1 C
= 220 F
OUT
T
= 25°C
A
0.01 1001010.1 100 IO, OUTPUT CURRENT (mA)
Figure 6. NCP1450ASN19T1 Efficiency vs.
Output Current
100
EFFICIENCY (%)
80
V V V V
= 4.0 V
IN
= 3.0 V
IN
= 2.5 V
IN
= 2.0 V
IN
V
= 4.5 V
IN
V
= 1.2 V
IN
60
V
= 0.9 V
IN
V
IN
40
NCP1450ASN50T1 L = 10 H
20
0
0.01 1001010.1 100
Q = NTGS3446T1 C
= 220 F
OUT
T
= 25°C
A
IO, OUTPUT CURRENT (mA)
= 2.5 V
= 2.0 V
= 1.5 V
Figure 7. NCP1450ASN30T1 Efficiency vs.
Output Current
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Figure 8. NCP1450ASN50T1 Efficiency vs.
Output Current
5
NCP1450A
V
, OUTPUT VOLTAGE (V)
I
, OPERATING CURRENT (
A)
0
0
0
2.1
2.0
1.9
1.8 NCP1450ASN19T1
, OUTPUT VOLTAGE (V)
L = 22 H
1.7
OUT
V
= 0 mA
I
O
V
= 1.2 V
IN
1.6
−50 50250−25 75 100 −50 50250−25 75 10 TEMPERATURE (°C)
Figure 9. NCP1450ASN19T1 Output Voltage
vs. Temperature
3.2
3.1
3.0
2.9
, OUTPUT VOLTAGE (V)
2.8
OUT
V
2.7
NCP1450ASN30T1 L = 22 H
= 0 mA
I
O
V
= 1.2 V
IN
TEMPERATURE (°C)
Figure 10. NCP1450ASN30T1 Output Voltage
vs. Temperature
5.2
5.1
5.0
100
80
60
4.9 NCP1450ASN50T1
L = 22 H
4.8
OUT
4.7
= 0 mA
I
O
V
IN
= 1.2 V
−50 50250−25 75 100 TEMPERATURE (°C)
Figure 11. NCP1450ASN50T1 Output Voltage
vs. Temperature
40
, OPERATING CURRENT (A) I
DD
V
= 1.9 V x 0.96
OUT
Open−Loop Test
NCP1450ASN19T1
20
0
−50 50250−25 75 10 TEMPERATURE (°C)
Figure 12. NCP1450ASN19T1 Operating
Current vs. Temperature
, OPERATING CURRENT (A) I
DD
200
180
160
140
NCP1450ASN50T1
120
V
OUT
Open−Loop Test
100
Figure 14. NCP1450ASN50T1 Operating
= 5.0 V x 0.96
TEMPERATURE (°C)
Current vs. Temperature
140
120
100
80
NCP1450ASN30T1
60
V
= 3.0 V x 0.96
DD
OUT
Open−Loop Test
40
−50 50250−25 75 100 −50 50250−25 75 10 TEMPERATURE (°C)
Figure 13. NCP1450ASN30T1 Operating
Current vs. Temperature
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NCP1450A
I
, STANDBY CURRENT (
A)
I
, OFF−STATE CURRENT (
A)
0
0
0
25
20
15
10
, STANDBY CURRENT (A)
STD
I
NCP1450ASN19T1
5
V
= 1.9 V + 0.5 V
OUT
Open−Loop Test
0
−50 50250−25 75 100 TEMPERATURE (°C)
Figure 15. NCP1450ASN19T1 Standby Current
vs. Temperature
25
20
15
25
20
15
10
, STANDBY CURRENT (A)
STD
I
NCP1450ASN30T1
5
V
= 3.0 V + 0.5 V
OUT
Open−Loop Test
0
−50 50250−25 75 10 TEMPERATURE (°C)
Figure 16. NCP1450ASN30T1 Standby Current
vs. Temperature
1.0 NCP1450ASN19T1
V
= 5.0 V
OUT
0.8
0.6
= 0 V
V
CE
Open−Loop Test
STD
OFF
10
NCP1450ASN50T1
5
V
= 5.0 V + 0.5 V
OUT
Open−Loop Test
0
−50 50250−25 75 100 TEMPERATURE (°C)
Figure 17. NCP1450ASN50T1 Standby Current
vs. Temperature
1.0 NCP1450ASN30T1 V
= 5.0 V
OUT
0.8
= 0 V
V
CE
Open−Loop Test
0.6
0.4
0.2
0.0
−50 50250−25 75 100 TEMPERATURE (°C)
Figure 19. NCP1450ASN30T1 Off−State Current
vs. Temperature
0.4
0.2
, OFF−STATE CURRENT (A)
OFF
I
0.0
−50 50250−25 75 10 TEMPERATURE (°C)
Figure 18. NCP1450ASN19T1 Off−State Current
vs. Temperature
1.2 NCP1450ASN50T1 V
= 5.0 V
OUT
1.0
= 0 V
V
CE
Open−Loop Test
0.8
0.6
0.4
, OFF−STATE CURRENT (A)
OFF
I
0.2
−50 50250−25 75 10 TEMPERATURE (°C)
Figure 20. NCP1450ASN50T1 Off−State Current
vs. Temperature
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NCP1450A
0
D
, MAXIMUM DUTY CYCLE (%)
0
0
300
250
200
150
100
NCP1450ASN19T1
50
V
= 1.9 V x 0.96
, OSCILLATOR FREQUENCY (kHz)
OSC
f
OUT
Open−Loop Test
0
−50 50250−25 75 100 TEMPERATURE (°C)
Figure 21. NCP1450ASN19T1 Oscillator
Frequency vs. Temperature
300
250
200
300
250
200
150
100
NCP1450ASN30T1
50
V
= 3.0 V x 0.96
, OSCILLATOR FREQUENCY (kHz)
OSC
f
OUT
Open−Loop Test
0
−50 50250−25 75 10 TEMPERATURE (°C)
Figure 22. NCP1450ASN30T1 Oscillator
Frequency vs. Temperature
100
90
80
150
100
NCP1450ASN50T1
50
V
, OSCILLATOR FREQUENCY (kHz)
OSC
f
OUT
Open−Loop Test
0
−50 50250−25 75 100
Figure 23. NCP1450ASN50T1 Oscillator
100
90
80
70
60
NCP1450ASN30T1
50
V
MAX
OUT
Open−Loop Test
40
−50 50250−25 75 100
Figure 25. NCP1450ASN30T1 Maximum Duty
= 5.0 V x 0.96
TEMPERATURE (°C)
Frequency vs. Temperature
= 3.0 V x 0.96
TEMPERATURE (°C)
Cycle vs. Temperature
70
60
MAXIMUM DUTY CYCLE (%)
MAX,
D
NCP1450ASN19T1
50
V
= 1.9 V x 0.96
OUT
Open−Loop Test
40
−50 50250−25 75 10
TEMPERATURE (°C)
Figure 24. NCP1450ASN19T1 Maximum Duty
Cycle vs. Temperature
100
90
80
70
60
, MAXIMUM DUTY CYCLE (%)
MAX
D
NCP1450ASN50T1
50
V
OUT
Open−Loop Test
= 5.0 V x 0.96
40
−50 50250−25 75 10
TEMPERATURE (°C)
Figure 26. NCP1450ASN50T1 Maximum Duty
Cycle vs. Temperature
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NCP1450A
I
, EXT “H” OUTPUT CURRENT (mA)
I
, EXT “H” OUTPUT CURRENT (mA)
0
I
, EXT “L” OUTPUT CURRENT (mA)
0
0
0
−10
−20
−30 NCP1450ASN19T1
V
= 1.9 V x 0.96
V
OUT EXT
= V
−40 Open−Loop Test
EXTH
−50
−50 50250−25 75 100
Figure 27. NCP1450ASN19T1 EXT “H” Output
−40
−50
−60
− 0.4 V
OUT
TEMPERATURE (°C)
Current vs. Temperature
−20
−30
−40
−50 NCP1450ASN30T1
V
= 3.0 V x 0.96
V
OUT EXT
= V
OUT
− 0.4 V
−60
, EXT “H” OUTPUT CURRENT (mA)
Open−Loop Test
EXTH
I
−70
−50 50250−25 75 10 TEMPERATURE (°C)
Figure 28. NCP1450ASN30T1 EXT “H” Output
Current vs. Temperature
50
40
30
−70 NCP1450ASN50T1
V
= 5.0 V x 0.96
V
OUT EXT
= V
−80 Open−Loop Test
EXTH
−90
−50 50250−25 75 100
Figure 29. NCP1450ASN50T1 EXT “H” Output
80
70
60
50
NCP1450ASN30T1 V
= 3.0 V x 0.96
OUT
40
V
EXT
= 0.4 V
Open−Loop Test
EXTL
30
−50 50250−25 75 100
Figure 31. NCP1450ASN30T1 EXT “L” Output
− 0.4 V
OUT
TEMPERATURE (°C)
Current vs. Temperature
TEMPERATURE (°C)
Current vs. Temperature
20
NCP1450ASN19T1 V
= 1.9 V x 0.96
OUT
10
, EXT “L” OUTPUT CURRENT (mA)
EXTL
I
0
−50 50250−25 75 10
= 0.4 V
V
EXT
Open−Loop Test
TEMPERATURE (°C)
Figure 30. NCP1450ASN19T1 EXT “L” Output
Current vs. Temperature
90
80
70
60
NCP1450ASN50T1 V
= 5.0 V x 0.96
OUT
50
, EXT “L” OUTPUT CURRENT (mA)
EXTL
I
40
= 0.4 V
V
EXT
Open−Loop Test
−50 50250−25 75 10 TEMPERATURE (°C)
Figure 32. NCP1450ASN50T1 EXT “L” Output
Current vs. Temperature
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NCP1450A
R
, EXT “H” ON−RESISTANCE (
)
0
0
0
25
20
15
10
NCP1450ASN19T1
, EXT “H” ON−RESISTANCE ()
R
V
EXTH
EXT
Open−Loop Test
0
−50 50250−25 75 100 −50 50250−25 75 10
= V
OUT
− 0.4 V
= 1.9 V x 0.96
V
OUT
5
TEMPERATURE (°C)
Figure 33. NCP1450ASN19T1 EXT “H”
ON−Resistance vs. Temperature
25
20
15
10
NCP1450ASN30T1 V
5
, EXT “H” ON−RESISTANCE ()
V
EXTH
Open−Loop Test
R
0
= 3.0 V x 0.96
OUT EXT
= V
OUT
− 0.4 V
TEMPERATURE (°C)
Figure 34. NCP1450ASN30T1 EXT “H”
ON−Resistance vs. Temperature
25
NCP1450ASN50T1 V
OUT
20
= V
V
EXT
= 5.0 V x 0.96
− 0.4 V
OUT
Open−Loop Test
15
25
NCP1450ASN19T1 V
OUT
20
V
EXT
Open−Loop Test
15
= 1.9 V x 0.96
= 0.4 V
10
5
EXTH
0
−50 50250−25 75 100 TEMPERATURE (°C)
Figure 35. NCP1450ASN50T1 EXT “H”
ON−Resistance vs. Temperature
10
, EXT “L” ON−RESISTANCE ()
5
EXTL
R
0
−50 50250−25 75 10 TEMPERATURE (°C)
Figure 36. NCP1450ASN19T1 EXT “L”
ON−Resistance vs. Temperature
25
NCP1450ASN30T1 V
= 3.0 V x 0.96
OUT
20
V
EXT
= 0.4 V
Open−Loop Test
15
10
, EXT “L” ON−RESISTANCE ()
5
EXTL
R
0
25
NCP1450ASN50T1 V
= 5.0 V x 0.96
OUT
20
V
EXT
= 0.4 V
Open−Loop Test
15
10
, EXT “L” ON−RESISTANCE ()
5
EXTL
R
0
−50 50250−25 75 100 −50 50250−25 75 10 TEMPERATURE (°C)
TEMPERATURE (°C)
Figure 37. NCP1450ASN30T1 EXT “L”
ON−Resistance vs. Temperature
Figure 38. NCP1450ASN50T1 EXT “L”
ON−Resistance vs. Temperature
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10
NCP1450A
V
, RIPPLE VOLTAGE (mV)
0
0
0
1.0
0.8 V
start
0.6
NCP1450ASN19T1 L = 22 H C
= 0.1 F
OUT
0.4
I
= 0 mA
O
STARTUP/HOLD VOLTAGE (V)
0.2
hold,
/V
start
0.0
V
−50 50250−25 75 100 −50 50250−25 75 10
V
hold
TEMPERATURE (°C)
Figure 39. NCP1450ASN19T1 Startup/Hold
V oltage vs. Temperature
1.0
0.8
0.6
0.4
STARTUP/HOLD VOLTAGE (V)
0.2
hold,
/V
start
0.0
V
V
start
NCP1450ASN30T1 L = 22 H C
= 0.1 F
OUT
I
= 0 mA
O
V
hold
TEMPERATURE (°C)
Figure 40. NCP1450ASN30T1 Startup/Hold
V oltage vs. Temperature
1.0
0.8
V
start
0.6
0.4
NCP1450ASN50T1
STARTUP/HOLD VOLTAGE (V)
0.2
L = 22 H
hold,
C
= 0.1 F
/V
start
V
OUT
I
= 0 mA
O
0.0
−50 50250−25 75 100
V
hold
TEMPERATURE (°C)
200
NCP1450ASN19T1
180
L = 10 H
160
Q = NTGS3446T1
= 220 F
C T
A
OUT
= 25°C
V
= 0.9 V
IN
V
= 1.2 V
IN
140 120 100
80 60
, RIPPLE VOLTAGE (mV)
40
RIPPLE
20
V
0
0 800600400200 100
IO, OUTPUT CURRENT (mA)
V
= 1.5 V
IN
Figure 41. NCP1450ASN50T1 Startup/Hold
V oltage vs. Temperature
200
NCP1450ASN30T1
180
L = 10 H
160
Q = NTGS3446T1 C
OUT
140
T
A
120 100
= 220 F
= 25°C
V
IN
= 0.9 V
V
= 1.2 V
IN
V
= 1.5 V
IN
80 60 40
RIPPLE
20
V
IN
= 2.0 V
V
IN
0
0 800600400200 1000
IO, OUTPUT CURRENT (mA)
Figure 43. NCP1450ASN30T1 Ripple Voltage
vs. Output Current
= 2.5 V
, RIPPLE VOLTAGE (mV)
RIPPLE
V
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11
Figure 42. NCP1450ASN19T1 Ripple Voltage
vs. Output Current
200 180 160
140 120 100
80 60 40 20
V
= 0.9 V
IN
V
IN
= 1.2 V
V
= 1.5 V
IN
V
= 2.0 V
IN
V
= 2.5 V
IN
NCP1450ASN50T1 L = 10 H Q = NTGS3446T1 C
OUT
T
= 25°C
A
V
= 3.0 V
IN
V
= 4.0 V
IN
= 220 F
V
= 4.5 V
IN
0
0 800600400200 100
IO, OUTPUT CURRENT (mA)
Figure 44. NCP1450ASN50T1 Ripple Voltage
vs. Output Current
NCP1450A
V
/V
STARTUP/HOLD VOLTAGE (V)
V
/V
STARTUP/HOLD VOLTAGE (V)
V
/V
STARTUP/HOLD VOLTAGE (V)
0
0
0
2.0
1.6
1.2
V
start
NCP1450ASN19T1 L = 10 H
2.0 NCP1450ASN19T1
L = 10 H Q = MMJT9410
1.6 C
OUT
T
= 25°C
A
1.2
= 220 F
V
start
Q = NTGS3446T1
= 220 F
C
hold,
start
0.8
0.4
0.0
V
hold
0
I
, OUTPUT CURRENT (mA)
O
T
604020
Figure 45. NCP1450ASN19T1 Startup/Hold
Voltage vs. Output Current (Using MOSFET)
OUT
= 25°C
A
80 100
0.8
STARTUP/HOLD VOLTAGE (V)
0.4
hold,
/V
start
0.0
V
0604020 80 10
, OUTPUT CURRENT (mA)
I
O
V
hold
Figure 46. NCP1450ASN19T1 Startup/Hold
Voltage vs. Output Current (Using BJT)
2.0
1.6
V
start
2.0
1.6
V
start
NCP1450ASN30T1
1.2
0.8
L = 10 H Q = NTGS3446T1
= 220 F
C
OUT
T
= 25°C
A
1.2
0.8
V
hold
NCP1450ASN30T1
V
hold
hold,
start
0.4
0.0 0604020 80 100 0 604020 80 10
IO, OUTPUT CURRENT (mA)
STARTUP/HOLD VOLTAGE (V)
0.4
hold,
/V
start
0.0
V
IO, OUTPUT CURRENT (mA)
L = 10 H Q = MMJT9410
= 220 F
C
OUT
T
= 25°C
A
Figure 47. NCP1450ASN30T1 Startup/Hold
Voltage vs. Output Current (Using MOSFET)
Figure 48. NCP1450ASN30T1 Startup/Hold
Voltage vs. Output Current (Using BJT)
2.0
V
1.6
1.2
0.8
start
V
hold
NCP1450ASN50T1 L = 10 H
0.4
hold,
0.0
start
0604020 80 100 0 604020 80 10
Q = NTGS3446T1
= 220 F
C
OUT
T
= 25°C
A
IO, OUTPUT CURRENT (mA)
Figure 49. NCP1450ASN50T1 Startup/Hold
Voltage vs. Output Current (Using MOSFET)
2.0
1.6
1.2
0.8
STARTUP/HOLD VOLTAGE (V)
0.4
hold,
/V
0.0
start
V
V
start
V
hold
NCP1450ASN50T1 L = 10 H Q = MMJT9410
= 220 F
C
OUT
T
= 25°C
A
IO, OUTPUT CURRENT (mA)
Figure 50. NCP1450ASN50T1 Startup/Hold
Voltage vs. Output Current (Using BJT)
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NCP1450A
2 s/div
V
= 1.9 V, VIN = 1.2 V, IO = 20 mA, L = 10 H,
OUT
, 1.0 V/div
1. V
L
2. I
, 500 mA/div
L
3. V
, 50 mV/div, AC coupled
OUT
C
OUT
= 220 F
Figure 51. NCP1450ASN19T1 Operating
Waveforms (Medium Load)
2 s/div
V
= 3.0 V, VIN = 1.8 V, IO = 20 mA, L = 10 H,
OUT
1. V
, 2.0 V/div
L
2. I
, 500 mA/div
L
3. V
, 50 mV/div, AC coupled
OUT
C
OUT
= 220 F
Figure 53. NCP1450ASN30T1 Operating
Waveforms (Medium Load)
2 s/div
V
= 1.9 V, VIN = 1.2 V, IO = 500 mA, L = 10 H,
OUT
, 1.0 V/div
1. V
L
2. I
, 500 mA/div
L
3. V
, 50 mV/div, AC coupled
OUT
C
OUT
= 220 F
Figure 52. NCP1450ASN19T1 Operating
Waveforms (Heavy Load)
2 s/div
= 3.0 V, VIN = 1.8 V, IO = 500 mA, L = 10 H,
V
OUT
1. V
, 2.0 V/div
L
2. I
, 500 mA/div
L
3. V
, 50 mV/div, AC coupled
OUT
C
OUT
= 220 F
Figure 54. NCP1450ASN30T1 Operating
Waveforms (Heavy Load)
2 s/div
V
= 5.0 V, VIN = 3.0 V, IO = 20 mA, L = 10 H,
OUT
1. V
, 2.0 V/div
L
2. I
, 500 mA/div
L
3. V
, 50 mV/div, AC coupled
OUT
C
OUT
= 220 F
Figure 55. NCP1450ASN50T1 Operating
Waveforms (Medium Load)
1. V
2. I
3. V
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13
2 s/div
V
= 5.0 V, VIN = 3.0 V, IO = 500 mA, L = 10 H,
OUT
, 2.0 V/div
L
, 500 mA/div
L
, 50 mV/div, AC coupled
OUT
C
OUT
= 220 F
Figure 56. NCP1450ASN50T1 Operating
Waveforms (Heavy Load)
NCP1450A
1. V
VIN = 1.5 V, L = 4.7 H, C
, 1.9 V (AC coupled), 200 mV/div
OUT
, 1.0 mA to 100 mA
2. I
O
OUT
= 220 F
Figure 57. NCP1450ASN19T1 Load Transient
Response
= 2.0 V, L = 4.7 H, C
V
1. V
2. I
IN
, 3.0 V (AC coupled), 200 mV/div
OUT
, 1.0 mA to 100 mA
O
OUT
= 220 F
Figure 59. NCP1450ASN30T1 Load Transient
Response
1. V
VIN = 1.5 V, L = 4.7 H, C
, 1.9 V (AC coupled), 200 mV/div
OUT
, 100 mA to 1.0 mA
2. I
O
OUT
= 220 F
Figure 58. NCP1450ASN19T1 Load Transient
Response
= 2.0 V, L = 4.7 H, C
V
1. V
2. I
IN
, 3.0 V (AC coupled), 200 mV/div
OUT
, 100 mA to 1.0 mA
O
OUT
= 220 F
Figure 60. NCP1450ASN30T1 Load Transient
Response
1. V
VIN = 3.0 V, L = 4.7 H, C
, 5.0 V (AC coupled), 200 mV/div
OUT
, 1.0 mA to 100 mA
2. I
O
OUT
= 220 F
Figure 61. NCP1450ASN50T1 Load Transient
Response
1. V
2. I
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14
V
= 3.0 V, L = 4.7 H, C
IN
, 5.0 V (AC coupled), 200 mV/div
OUT
, 100 mA to 1.0 mA
O
OUT
= 220 F
Figure 62. NCP1450ASN50T1 Load Transient
Response
NCP1450A
V
, OUTPUT VOLTAGE (V)
EFFICIENCY (%)
0
0
0
2.1
V
2.0
= 1.5 V
IN
1.9
NCP1450ASN19T1
1.8
V
= 0.9 V V
IN
= 1.2 V
IN
, OUTPUT VOLTAGE (V)
1.7
OUT
V
1.6 0 600400200 800 1000
, OUTPUT CURRENT (mA)
I
O
L = 10 H Q = MMJT9410 Rb = 560 C
= 0.003 F
b
C
= 220 F
OUT
T
= 25°C
A
Figure 63. NCP1450ASN19T1 Output Voltage
vs. Output Current (Ext. BJT)
5.2
V
= 4.5 V
IN
V
= 4.0 V
V
IN
IN
= 3.0 V
5.1
IN
= 1.5 V
V
= 2.5 VV
IN
5.0
NCP1450ASN50T1 L = 10 H Q = MMJT9410
= 560
R
b
C
= 0.003 F
b
= 220 F
C
OUT
= 25°C
T
A
600
800 1000
OUT
4.9
4.8
4.7
V
= 2.0 V
IN
V
= 1.2 V
IN
V
= 0.9 V
IN
0
400200
IO, OUTPUT CURRENT (mA)
Figure 65. NCP1450ASN50T1 Output Voltage
vs. Output Current (Ext. BJT)
100
V
= 2.5 V
IN
V
= 2.0 V
IN
80
= 1.5 V
V
IN
V
= 1.2 V
IN
V
= 0.9 V
IN
60
40
NCP1450ASN30T1 L = 10 H Q = MMJT9410
= 560
R
20
0
b
C
= 0.003 F
b
= 220 F
C
OUT
= 25°C
T
A
0.01 1010.1 100 1000 IO, OUTPUT CURRENT (mA)
3.2
3.1 = 2.0 V
IN
V
= 2.5 VV
IN
3.0
V
= 1.5 V
2.9
V
= 0.9 V
, OUTPUT VOLTAGE (V)
OUT
V
IN
2.8
2.7
0 600400200 800 100
V
= 1.2 V
IN
IN
NCP1450ASN30T1 L = 10 H Q = MMJT9410 Rb = 560 C
= 0.003 F
b
C
= 220 F
OUT
T
= 25°C
A
IO, OUTPUT CURRENT (mA)
Figure 64. NCP1450ASN30T1 Output Voltage
vs. Output Current (Ext. BJT)
100
V
= 1.5 V
80
V
= 1.2 V
IN
IN
60
NCP1450ASN19T1
40
EFFICIENCY (%)
20
V
= 0.9 V
IN
0
0.01 1010.1 100 100
L = 10 H Q = MMJT9410
= 560
R
b
C
= 0.003 F
b
C
= 220 F
OUT
T
= 25°C
A
IO, OUTPUT CURRENT (mA)
Figure 66. NCP1450ASN19T1 Efficiency vs.
Output Current (Ext. BJT)
100
EFFICIENCY (%)
V
80
60
40
V V V
V
= 4.0 V
IN
= 3.0 V
IN
= 2.5 V
IN
= 2.0 V
IN
= 0.9 V
IN
V
= 4.5 V
IN
V
IN
V
IN
NCP1450ASN50T1 L = 10 H Q = MMJT9410
= 560
R
20
0
b
C
= 0.003 F
b
= 220 F
C
OUT
= 25°C
T
A
0.01 1010.1 100 100 IO, OUTPUT CURRENT (mA)
= 1.5 V = 1.2 V
Figure 67. NCP1450ASN30T1 Efficiency vs.
Output Current (Ext. BJT)
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Figure 68. NCP1450ASN50T1 Efficiency vs.
Output Current (Ext. BJT)
15
NCP1450A
10
100
Á
Á
Á
Á
Á
NCP1450ASNXXT1 L = 10 H Q = NTGS3446T1 C
= 220 F
V
OUT
OUT
T
= 25°C
A
= 5.0 V
1
0.1
V
= 3.0 V
, NO LOAD INPUT CURRENT (mA)
IN
I
0.01 14
V
OUT
= 1.9 V
OUT
32
51 43250
VIN, INPUT VOLTAGE (V)
10
1
0.1
, NO LOAD INPUT CURRENT (mA)
IN
I
0.01
A. V
= 1.9 V, Rb = 1 k
F C
E
B
OUT
= 3.0 V, Rb = 1 k
B. V
OUT
C. V
= 5.0 V, Rb = 1 k
OUT
= 1.9 V, Rb = 560
D. V
OUT
E. V
= 3.0 V, Rb = 560
OUT
= 5.0 V, Rb = 560
F. V
OUT
NCP1450ASNXXT1 L = 10 H
D
Q = MMJT9410
= 220 F
C
OUT
= 25°C
T
A
A
VIN, INPUT VOLTAGE (V)
Figure 69. NCP1450ASNXXT1 No Load Input
Current vs. Input Voltage (Using MOSFET)
Components Supplier
Parts Supplier Part Number Description Phone
Inductor: L1, L2 Schottky Diode: D1, D2 MOSFET: Q1 BJT: Q2 Output Capacitor: C1, C3
ББББББ
Input Capacitor: C2, C4
Sumida Electric Co. Ltd. ON Semiconductor ON Semiconductor ON Semiconductor KEMET Electronics Corp.
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KEMET Electronics Corp.
CD54−100MC MBRM110L NTGS3446T1 MMJT9410 T494D227K006AS
ÁÁÁÁ
T491C106K016AS
Figure 70. NCP1450ASNXXT1 No Load Input
Current vs. Input Voltage (Using BJT)
Inductor 10 H/1.44 A Schottky Power Rectifier Power MOSFET N−Channel Bipolar Power Transistor Low ESR Tantalum Capacitor
220 F/6.0 V
БББББББ
Low Profile Tantalum Capacitor
10 F/16 V
(852) 2880−6688 (852) 2689−0088 (852) 2689−0088 (852) 2689−0088 (852) 2305−1168
ÁÁÁÁ
(852) 2305−1168
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16
NCP1450A
DETAILED OPERATING DESCRIPTION
Operation
The NCP1450A series are monolithic power switching controllers optimized for battery powered portable products where large output current is required.
The NCP1450A series are low noise fixed frequency voltage−mode PWM DC−DC controllers, and consist of startup circuit, feedback resistor divider, reference voltage, oscillator, loop compensation network, PWM control circuit, and low ON resistance driver. Due to the on−chip feedback resistor and loop compensation network, the system designer can get the regulated output voltage from
1.8 V to 5.0 V with 0.1 V stepwise with a small number of external components. The quiescent current is typically 93 A (V reduced to about 1.5 A when the chip is disabled (V
OUT
= 2.7 V, f
= 180 kHz), and can be further
OSC
CE
t
0.3 V).
The NCP1450A operation can be best understood by referring to the block diagram in Figure 2. The error amplifier monitors the output voltage via the feedback resistor divider by comparing the feedback voltage with the reference voltage. When the feedback voltage is lower than the reference voltage, the error amplifier output will decrease. The error amplifier output is then compared with the oscillator ramp voltage at the PWM controller. When the ramp voltage is higher than the error amplifier output, the high−side driver is turned on and the low−side driver is turned off which will then switch on the external transistor; and vice versa. As the error amplifier output decreases, the high−side driver turn−on time increases and duty cycle increases. When the feedback voltage is higher than the reference voltage, the error amplifier output increases and the duty cycle decreases. When the external power switch is on, the current ramps up in the inductor, storing energy in the magnetic field. When the external power switch is off, the energy stored in the magnetic field is transferred to the output filter capacitor and the load. The output filter capacitor stores the charge while the inductor current is higher than the output current, then sustains the output voltage until the next switching cycle.
As the load current is decreased, the switch transistor turns on for a shorter duty cycle. Under the light load condition, the controller will skip switching cycles to reduce power consumption, so that high efficiency is maintained at light loads.
Soft Start
There is a soft start circuit in NCP1450A. When power is applied to the device, the soft start circuit first pumps up the output voltage to approximately 1.5 V at a fixed duty cycle. This is the voltage level at which the controller can operate normally. In addition to that, the startup capability with heavy loads is also improved.
Oscillator
The oscillator frequency is internally set to 180 kHz at an accuracy of "20% and with low temperature coefficient of
0.11%/°C.
Regulated Converter Voltage (V
The V
is set by an integrated feedback resistor
OUT
OUT
)
network. This is trimmed to a selected voltage from 1.8 V to
5.0 V range in 100 mV steps with an accuracy of "2.5%.
Compensation
The device is designed to operate in continuous conduction mode. An internal compensation circuit was designed to guarantee stability over the full input/output voltage and full output load range.
Enable/Disable Operation
The NCP1450A series offer IC shutdown mode by chip enable pin (CE pin) to reduce current consumption. When voltage at pin CE is equal or greater than 0.9 V, the chip will be enabled, which means the controller is in normal operation. When voltage at pin CE is less than 0.3 V, the chip is disabled, which means IC is shutdown.
Important: DO NOT apply a voltage between 0.3 V to 0.9 V to pin CE as this is the CE pin’s hysteresis voltage range. Clearly defined output states can only be obtained by applying voltage out of this range.
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17
NCP1450A
Á
Á
Á
Á
Á
Á
APPLICATION CIRCUIT INFORMATION
Step−up Converter Design Equations
The NCP1450A PWM step−up DC−DC controller is designed to operate in continuous conduction mode and can be defined by the following equations. External components values can be calculated from these equations, however, the optimized value should obtained through experimental results.
Calculation Equation
D
I
ÁÁÁÁ
ÁÁÁÁ
ÁÁÁÁ
NOTES: D − On−time duty cycle IL− Average inductor current I
PK
DIR − Delta inductor current to average inductor current ratio I
O
V V V V
ESR
L
L
I
PK
Q
V
PP
− Peak inductor current
− Desired dc output current
− Nominal operating dc input voltage
IN
− Desired dc output voltage
OUT
− Diode forward voltage
D
− Saturation voltage of the external transistor switch
S
− Charge stores in the C
Q
− Equivalent series resistance of the output capacitor
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V
OUT
v
V
OUT
(V
) VD* VIN)(1 * D)
OUT
f IO DIR
IL(1 )
(IL* IO)(1 * D)
Q
[
) (IL* IO) ESR
C
OUT
during charging up
OUT
) VD* V
) VD* V
I
O
(1 * D)
DIR
2
f
IN
S
2
)
Design Example
It is supposed that a step−up DC−DC controller with 3.3 V output delivering a maximum 1000 mA output current with 100 mV output ripple voltage powering from a 2.4 V input is to be designed.
Design parameters:
V
= 2.4 V
IN
V
= 3.3 V
OUT
I
= 1.0 A
O
V
= 100 mV
pp
f = 180 kHZ
DIR = 0.2 (typical for small output ripple voltage)
Assume the diode forward voltage and the transistor saturation voltage are both 0.3 V. Determine the maximum steady state duty cycle at V
3.3V ) 0.3V * 2.4V
D +
3.3V ) 0.3V * 0.3V
= 2.4 V:
IN
+ 0.364
Calculate the maximum inductance value which can generate the desired current output and the preferred delta inductor current to average inductor current ratio:
(3.3V ) 0.3V * 2.4V)(1 * 0.364)
L v
180000Hz 1A 0.2
2
+ 13.5H
Determine the average inductor current and peak inductor current:
+
1 * 0.364
1
+ 1.57A
0.2
) + 1.73A
2
I
L
IPK+ 1.57A (1 )
Therefore, a 12 H inductor with saturation current lar ger than 1.73 A can be selected as the initial trial.
Calculate the delta charge stored in the output capacitor during the charging up period in each switching cycle:
(1.57A * 1A)(1 * 0.364)
Q +
18000Hz
+ 2.01C
Determine the output capacitance value for the desired output ripple voltage:
Assume the ESR of the output capacitor is 0.15 ,
C
OUT
u
100mV * (1.57A * 1A) 0.15
2.01C + 138.6F
Therefore, a Tantalum capacitor with value of 150 F to 220 F and ESR of 0.15  can be used as the output capacitor. However, according to experimental result, 220F output capacitor gives better overall operational stability and smaller ripple voltage.
External Component Selection
Inductor Selection
The NCP1450A is designed to work well with a 6.8 to 12 H inductors in most applications 10 H is a s u fficiently low value to allow the use of a small surface mount coil, but large enough to maintain low ripple. Lower inductance values supply higher output current, but also increase the ripple and reduce efficiency.
Higher inductor values reduce ripple and improve efficiency, but also limit output current.
The inductor should have small DCR, usually less than 1, to minimize loss. It is necessary to choose an inductor with a saturation current greater than the peak current which the inductor will encounter in the application.
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NCP1450A
Diode
The diode is the largest source of loss in DC−DC converters. The most importance parameters which affect their efficiency are the forward voltage drop, V
, and the
D
reverse recovery time, trr. The forward voltage drop creates a loss just by having a voltage across the device while a current flowing through it. The reverse recovery time generates a loss when the diode is reverse biased, and the current appears to actually flow backwards through the diode due to the minority carriers being swept from the P−N junction. A Schottky diode with the following characteristics is recommended:
Small forward voltage, V
t 0.3 V
F
Small reverse leakage current Fast reverse recovery time/switching speed Rated current larger than peak inductor current,
I
u I
rated
PK
Reverse voltage larger than output voltage,
V
u V
reverse
Input Capacitor
OUT
The input capacitor can stabilize the input voltage and minimize peak current ripple from the source. The value of the capacitor depends on the impedance of the input source used. Small Equivalent Series Resistance (ESR) Tantalum or ceramic capacitor with a value of 10 F should be suitable.
Output Capacitor
The output capacitor is used for sustaining the output voltage when the external MOSFET or bipolar transistor is switched on and smoothing the ripple voltage. Low ESR capacitor should be used to reduce output ripple voltage. In general, a 100 F to 220 F low ESR (0.10 to 0.30 ) Tantalum capacitor should be appropriate.
External Switch Transistor
An enhancement N−channel MOSFET or a bipolar NPN transistor can be used as the external switch transistor.
For enhancement N−channel MOSFET, since enhancement MOSFET is a voltage driven device, it is a
more efficient switch than a BJT transistor. However, the MOSFET requires a higher voltage to turn on as compared with BJT transistors. An enhancement N−channel MOSFET can be selected by the following guidelines:
1. Low ON−resistance, R
2. Low gate threshold voltage, V V
, typically < 1.5 V, it is especially important
OUT
for the low V
device, like V
OUT
3. Rated continuous drain current, I larger than the peak inductor current, i.e. I
, typically < 0.1 .
DS(on)
GS(th)
OUT
D
, must be <
= 1.9 V.
, should be
D
> IPK.
4. Gate capacitance should be 1200 pF or less.
For bipolar NPN transistor, medium power transistor with
continuous collector current typically 1 A to 5 A and V
CE(sat)
< 0.2 V should be employed. The driving capability is determined by the DC current gain, H
, of the transistor and
FE
the base resistor, Rb; and the controller’s EXT pin must be able to supply the necessary driving current.
Rb can be calculated by the following equation:
Rb +
V
OUT *
Ib
Ib +
0.7
I
H
PK
FE
*
|
I
EXTH
0.4 |
Since the pulse current flows through the transistor, the exact Rb value should be finely tuned by the experiment. Generally , a small Rb value can increase the output current capability, but the efficiency will decrease due to more energy is used to drive the transistor.
Moreover, a speed−up capacitor, Cb, should be connected in parallel with Rb to reduce switching loss and improve efficiency. Cb can be calculated by the equation below:
Cb v
2Rb f
1
OSC
0.7
It is due to the variation in the characteristics of the transistor used. The calculated value should be used as the initial test value and the optimized value should be obtained by the experiment.
External Component Reference Data
Inductor
Device V
NCP1450ASN19T1 1.9 V CD54 NCP1450ASN30T1 3.0 V CD54 NCP1450ASN50T1 5.0 V CD54 NCP1450ASN19T1 1.9 V CD54 NCP1450ASN30T1 3.0 V CD54 NCP1450ASN50T1 5.0 V CD54
OUT
Model
Inductor
Value
12 H 10 H 10 H 12 H 10 H 10 H
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External
Transistor
NTGS3446T1 MBRM110L NTGS3446T1 MBRM110L NTGS3446T1 MBRM110L
MMJT9410 MBRM110L MMJT9410 MBRM110L MMJT9410 MBRM110L
Diode
Output
Capacitor
220 F 220 F 220 F 220 F 220 F 220 F
NCP1450A
An evaluation board of NCP1450A has been made in the small size of 89 mm x 51 mm. The artwork and the silk screen of the surface−mount evaluation board PCB are shown in Figures 71 and 72. Please contact your
ON Semiconductor representative for availability. The evaluation board schematic diagrams are shown in Figures 73 and 74.
51 mm
89 mm
Figure 71. NCP1450A PWM Step−up DC−DC Controller Evaluation Board Silkscreen
51 mm
89 mm
Figure 72. NCP1450A PWM Step−up DC−DC Controller Evaluation Board Artwork (Component Side)
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NCP1450A
TP1
TP2
GND
TP5
V
TP6
GND
L1
CE
OUT
NC
10 H
NTGS3446T1
EXT
1
2
3
5
GND
NCP1450A
4
IC1
JP1
V
IN
C2
10 F
ON CE
OFF
C3
0.1 F
MBRM110L
Q1
Figure 73. NCP1450A Evaluation Board Schematic Diagram 1 (Step−up
DC−DC Converter Using External MOSFET Switch)
L2
10 H
JP2
IN
Rb
C5
10 F
ON
CE
OFF
C6
0.1 F
CE
1
OUT
2
NC
3
EXT
5
GND
NCP1450A
4
560
IC2
Cb
3000 pF
D1
D2
MBRM110L
Q2 MMJT9410
C1 220 F
C4 220 F
TP3 V
OUT
TP4 GND
TP7 V
TP8 GND
OUT
Figure 74. NCP1450A Evaluation Board Schematic Diagram 2 (Step−up
DC−DC Converter Using External Bipolar Transistor Switch)
PCB Layout Hints
Grounding
One point grounding should be used for the output power return ground, the input power return ground, and the device switch ground to reduce noise. In Figure 73, e.g.: C2 GND, C1 GND, and IC1 GND are connected at one point in the evaluation board. The input ground and output ground traces must be thick enough for current to flow through and for reducing ground bounce.
Power Signal Traces
Low resistance conducting paths should be used for the power carrying traces to reduce power loss so as to improve efficiency (short and thick traces for connecting the inductor L can also reduce stray inductance), e.g.: short and thick traces listed below are used in the evaluation board:
1. Trace from TP1 to L1
2. Trace from L1 to anode pin of D1
3. Trace from cathode pin of D1 to TP3
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Output Capacitor
The output capacitor should be placed close to the output terminals to obtain better smoothing effect on the output ripple.
Switching Noise Decoupling Capacitor
A 0.1 F ceramic capacitor should be placed close to the OUT pin and GND pin of the NCP1450A to filter the switching spikes in the output voltage monitored by the OUT pin.
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0.05 (0.002)
S
H
D
54
123
L
G
A
NCP1450A
PACKAGE DIMENSIONS
TSOP−5
SN SUFFIX
CASE 483−02
ISSUE E
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
B
J
C
K
M
OF BASE MATERIAL.
4. A AND B DIMENSIONS DO NOT INCLUDE MOLD FLASH, PROTRUSIONS, OR GATE BURRS.
DIM MIN MAX MIN MAX
A 2.90 3.10 0.1142 0.1220 B 1.30 1.70 0.0512 0.0669 C 0.90 1.10 0.0354 0.0433 D 0.25 0.50 0.0098 0.0197 G 0.85 1.05 0.0335 0.0413 H 0.013 0.100 0.0005 0.0040
J 0.10 0.26 0.0040 0.0102
K 0.20 0.60 0.0079 0.0236
L 1.25 1.55 0.0493 0.0610
M 0 10 0 10
__ _ _
S 2.50 3.00 0.0985 0.1181
INCHESMILLIMETERS
SOLDERING FOOTPRINT*
1.9
0.95
0.037
1.0
0.039
*For additional information on our Pb−Free strategy and soldering
details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D.
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.
0.074
0.028
0.7
2.4
0.094
SCALE 10:1
mm
ǒ
inches
Ǔ
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NCP1450A/D
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