AN78L20 Panasonic - SSG, AN78L20 Datasheet - Page 10

• Manufacturer Part Number: AN78L20
• Description: VOLTAGE REG POS 20V 100MA TO-92
• Manufacturer: Panasonic - SSG

Specifications of AN78L20

• Regulator Topology: Positive Fixed
• Voltage - Output: 20V
• Voltage - Input: Up to 40V
• Number Of Regulators: 1
• Current - Output: 100mA
• Operating Temperature: 0°C ~ 125°C
• Mounting Type: Through Hole
• Package / Case: TO-92-3 (Standard Body), TO-226
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Dropout (typical): -
• Current - Limit (min): -

AN78Lxx/AN78LxxM Series
I Basic Regulator Circuit
I Usage Notes
I Application Circuit Examples
10
1. Cautions for a basic circuit
2. Other caution items
1) Short-circuit between the input pin and GND pin
2) Floating of GND pin
Input
V
V
off when a large capacitance capacitor has been con-
nected to the IC's load, a voltage of a capacitor con-
nected to an output pin is applied between input/out-
put of the IC and this likely results in damage of the
IC. It is necessary, therefore, to connect a diode, as
shown in figure 2, to counter the reverse bias between
input/output pins.
thermal protection circuit inside the IC does not normally operate. In this state, if the load is short-circuited or
overloaded, it is likely to damage the IC.
C
I
0.33µF
C
I
I
I
If the input pin is short-circuitted to GND or is cut
If a GND pin is made floating in an operating mode, an unstabilized input voltage is outputted. In this case, a
20Ω
1
AN78Lxx
Q
1
1
3
1
AN78Lxx
Figure 1
D
2
2
3
i
3
2
C
O
Output
I
C
C
O
Note) V
0.1µF
I
O
is necessary when the input line is long.
improves the transient response.
C
V
V
O
V
O
O
O
Never fail to adjust individually with R
= V
O
varies due to sample to sample variation of I
O
V
' + I
I
Bias
C
C
D
1
AN78Lxx
I
O
i
SFF00005CEB
: When a wiring from a smoothing circuit to a three-pin regulator
: Normally unnecessary. But add it in the case that there is a
: When any sudden change of load current is likely to occur,
+ R
is long, it is likely to oscillate at output. A capacitor of 0.1µF to
0.47µF should be connected near an input pin.
connect an electrolytic capacitor of 10µF to 100µF to improve a
transitional response of output voltage.
residual voltage at the output capacitor Co even after switching
off the supply power because a current is likely to flow into an
output pin of the IC and damage the IC.
V
3
I
R
Bias
O
2
'
2
1
V
O
'
R
R
2
1
V
O
1
.
In
1
GND
Bias
Figure 2
.
2
3
Out
+
−
C
O
出力