NCP1445 ONSEMI [ON Semiconductor], NCP1445 Datasheet - Page 4

• Manufacturer Part Number: NCP1445
• Description: 4.0 A 280 kHz/560 kHz Boost Regulators
• Manufacturer: ONSEMI [ON Semiconductor]

4. Guaranteed by design, not 100% tested in production.
ELECTRICAL CHARACTERISTICS
NCP1442/3/4/5 specifications unless otherwise stated.) (See Note 2)
PACKAGE PIN DESCRIPTION
Power Switch
Switch Saturation Voltage
Switch Current Limit
Minimum Pulse Width
Switch Transconductance, DI
Switch Leakage
General
Operating Current
Shutdown Mode Current
Minimum Operation Input Voltage
Thermal Shutdown
Thermal Hysteresis
Package Pin Number
2 (NCP1442/4 only)
2 (NCP1443/5 only)
3 (NCP1442/4 only)
3 (NCP1443/5 only)
1
4
5
6
7
Characteristic
Pin Symbol
CC
GND
NFB
V
Test
V
SS
V
FB
/ DIV
SW
CC
C
SW
NCP1442, NCP1443, NCP1444, NCP1445
(continued) (2.7 V < V
Loop compensation pin. The V
compensation, current limit and soft start. Loop compensation can be implemented by a sim-
ple RC network as shown in the application diagram on page 2.
Positive regulator feedback pin. This pin senses a positive output voltage and is referenced to
1.276 V. When the voltage at this pin falls below 0.4 V, chip switching frequency reduces to
20% of the nominal frequency.
These pins are connected to internal test logic and should either be left floating or tied to
ground. Connection to a voltage between 2.0 V and 6.0 V shuts down the internal oscillator
and leaves the power switch running.
Negative feedback pin. This pin senses a negative output voltage and is referenced to −2.475
V. When the voltage at this pin goes above −0.65 V, chip switching frequency reduces to 20%
of the nominal frequency.
Ground pin. This pin provides a ground for the controller circuitry and the internal power
switch. This pin is internally connected to the metal pad of the package to provide an addition-
al ground connection as well as an effective means of dissipating heat.
High current switch pin. This pin connects internally to the collector of the power switch. The
open voltage across the power switch can be as high as 40 V. To minimize radiation, use a
trace as short as practical.
Synchronization and shutdown pin. This pin may be used to synchronize the part to nearly
twice the base frequency. A TTL low will shut the part down and put it into low current mode.
If synchronization is not used, this pin should be either tied high or left floating for normal
operation.
Input power supply pin. This pin supplies power to the part and should have a bypass capaci-
tor connected to GND.
I
I
I
50% duty cycle (Note 4)
80% duty cycle (Note 4)
FB = 0 V or NFB = 0 V, I
2.7 V
12 V < V
V
I
V
V
V
(Note 4)
(Note 4)
SWITCH
SWITCH
SWITCH
SW
SW
C
C
SW
< 0.8 V, SS = 0 V, 2.7 V
< 0.8 V, SS = 0 V, 12 V
= 0
= 40 V, V
switching, maximum I
V
= 4.0 A
= 10 mA, 2.7 V < V
= 10 mA,
CC
CC
http://onsemi.com
30 V, 10 mA
12 V, 10 mA
CC
Test Conditions
= 0V
CC
12 V < V
4
< 30 V; 0 C < T
SW
SW =
CC
C
CC
= 4.0 A (Note 4)
I
V
I
SW
pin is the output of the error amplifier and is used for loop
SW
V
< 30 V
CC
< 12 V
CC
10 mA
4.0 A
4.0 A
30 V
12 V
A
< 85 C; 0 C < T
Function
Min
200
150
5.0
4.0
J
−
−
−
−
−
−
−
−
−
−
−
< 125 C; For all
0.14
Typ
250
180
0.6
0.9
6.0
8.0
2.0
2.2
10
15
16
25
25
−
Max
300
210
1.0
0.5
0.4
8.0
2.6
30
50
20
27
60
60
−
−
mA/A
Unit
mA
mA
mA
ns
V
V
V
A
A
V
C
C