The shutdown (TSD) circuit is automatically latched OFF when the chip temperature exceeds the threshold temperature
after the programmed time period elapses, thus protecting the IC against “thermal runaway” and heat damage. Since the
TSD circuit is designed only to shut down the IC in the occurrence of extreme heat, it is important that the Tj(max)
parameter should not be exceeded in the thermal design, in order to avoid potential problems with the TSD.
7. IN
The IN line acts as the major current supply line, and is connected to the output N-Channel FET drain. Since there is no
electrical connection (such as between the VCC pin and the ESD protection diode) required, IN operates independent of
the input sequence. However, since an output N-Channel FET body diode exists between IN and OUT, a V
IN
-V
OUT
electric (diode) connection is present. Therefore, when output is switched ON or OFF, reverse current may flow from
OUT to IN.
8. PGOOD
It determines the status of the output voltage. This is an open-drain pin, which is connected to VCC pin through the
pull-up resistance (100kΩ or so). When the output voltage ranges from V
OUT
x 0.9 to V
OUT
x 1.1(TYP), the status is high.
Absolute Maximum Ratings
(Ta=25°C)
Parameter
Input Voltage 1
Input Voltage 2
Input Voltage 3
Input Voltage 4
Maximum Output Current
Enable Input Voltage
PGOOD Input Voltage
Power Dissipation 1
Power Dissipation 2
Power Dissipation 3
Power Dissipation 4
Operating Temperature Range
Storage Temperature Range
Maximum Junction Temperature
Symbol
V
CC
V
IN
V
DD
V
VD
I
OUT
V
EN
V
PGOOD
Pd1
Pd2
Pd3
Pd4
Topr
Tstg
Tjmax
Limit
6.0
(Note 1)
6.0
(Note 1)
6.0
(Note 1)
1
3
(Note 1)
6.0
6.0
0.34
(Note 2)
0.70
(Note 3)
2.21
(Note 4)
3.56
(Note 5)
-10 to +100
-55 to +125
+150
Unit
V
V
V
V
A
V
V
W
W
W
W
°C
°C
°C
(Note 1) Should not exceed Pd.
(Note 2) Derating in done 2.7mV/°C for operating above Ta ≥ 25°C no heat sink
(Note 3) Derating in done 5.6mV/°C for operating above Ta ≥ 25°C
PCB size:74.2mm x 74.2mm x 1.6mm when mounted on a 1-layer glass epoxy board(copper foil area : 10.29mm
2
)
(Note 4) Derating in done 17.7mV/°C for operating above Ta ≥ 25°C
PCB size:74.2mm x 74.2mm x 1.6mm when mounted on a 4-layer glass epoxy board(copper foil area : front and reverse 10.29mm
2
, 2nd and 3rd
5505mm
2
)
(Note 5) Derating in done 28.5mV/°C for operating above Ta ≥ 25°C
PCB size:74.2mm x 74.2mm x 1.6mm when mounted on a 4-layer glass epoxy board(copper foil area : each 5505mm
2
)
Caution:
Operating the IC over the absolute maximum ratings may damage the IC. The damage can either be a short circuit between pins or an open circuit
between pins and the internal circuitry. Therefore, it is important to consider circuit protection measures, such as adding a fuse, in case the IC is operated over
the absolute maximum ratings.
Recommended Operating Conditions
(Ta=25°C)
Parameter
Input Voltage 1
Input Voltage 2
Input Voltage 3
Output Voltage Setting Range
Enable Input Voltage
Symbol
V
CC
V
IN
V
DD
V
OUT
V
EN
Min
4.3
0.7
4.5
V
FB
-0.3
Max
5.5
V
CC
-1
(Note 6)
5.5
2.7
+5.5
Unit
V
V
V
V
V
(Note 6) VCC and IN do not have to be implemented in the order listed.
