tk71547as Toko Inc., tk71547as Datasheet - Page 10

• Manufacturer Part Number: tk71547as
• Description: Low Dropout Voltage Regulator
• Manufacturer: Toko Inc.

INPUT-OUTPUT CAPACITORS
Linear regulators require input and output capacitors in order to maintain regulator loop stability. The output capacitor
should be selected within the Equivalent Series Resistance (ESR) range as shown in the graphs below for stable
operation. The output capacitor C
increase as C
Note: It is very important to check the selected manufacturers electrical characteristics (capacitance and ESR) over
temperature.
Range which can be used:
Range which can be used: V
+ 2.2W
Capacitor used for evaluation: V
mF + 2.2W
TK715xxAS
Page 10
UNSTABLE AREA UNDER
AND TO THE LEFT
UNSTABLE AREA UNDER
AND TO THE LEFT
1.6
1.5
5.0
3.6
3.0
2.0
1.8
2.0
1.8
1.6
1.5
3.8
3.4
2.8
2.6
2.4
2.2
5.0
3.8
3.6
3.4
3.0
2.8
2.6
2.4
2.2
3.2
3.2
0
0
1.0 F
MULTI LAYER CERAMIC CAP
0.1 F
20
L
3.3 F
20
C L = 0.22 F ( TANTALUM) or More
is reduced, so the largest value of C
C L = 4.7 F MLCC or More
TANTALUM CAP
C L = 0.68 F MLCC
C L = 0.1 F TANTALUM
I OUT (mA)
I OUT (mA)
40
40
2.2 F
60
60
V
V
V
OUT
C IN = 0.1 F
OUT
OUT
OUT
C
IN
80
80
OUT
= 0.1 F
³ 1.9V I
³ 2.8V
L
³ 2.0V
³ 1.5V
can be reduced as the output voltage is increased. However, the output noise will
³ 1.5V I
APPLICATION INFORMATION
100
100
Stable area is
above the line
Stable area is
above the line
OUT
I
I
I
OUT
OUT
OUT
OUT
= 1 mA ~ Max, TANTALUM CAP. ³ 0.1 mF (CERAMIC CAP 0.22 mF
= 1 mA ~ Max, MULTI LAYER CERAMIC CAP. ³ 0.68 mF
= 1 mA ~ Max, MULTI LAYER CERAMIC CAP. ³ 1.0 mF
= 1 mA ~ Max, MULTI LAYER CERAMIC CAP. ³ 4.7 mF
= 1 mA ~ Max, TANTALUM CAP. ³ 0.22 mF (CERAMIC CAP 0.22
L
possilbe is recommended (C
0.68 F
0.1 F
C L
C L
4.7 F or More
0.22 F or More
L
= 4.7 mF or more).
ESR
ESR
March 2001 TOKO, Inc.
1.0
0.01