sg2002-xn5-tr sg-micro, sg2002-xn5-tr Datasheet - Page 9

• Manufacturer Part Number: sg2002-xn5-tr
• Description: 300ma, Low Power, Low Noise Low Dropout, Linear Regulators
• Manufacturer: sg-micro

TYPICAL OPERATING CHARACTERISTICS
V
Application Notes
When LDO is used in handheld products, Attention must be paid to voltage spike which would damage SG2002. In
such applications, voltage spike will be generated at changer interface and V
adapters and USB equipments are hot-inserted. Besides this, handheld products will be tested on the production line
on the condition of no battery. Test Engineer will apply power from the connector pin which connects with positive
pole of the battery. When external power supply is turned on suddenly, the voltage spike will be generated at the
battery connector. The voltage spike will be very high, it always exceeds the absolute maximum input voltage (6.0V)
of LDO. In order to get robust design. Design Engineer needs to clear up this voltage spike. Zener diode is a cheap
and effective solution to eliminate such voltage spike. For example, BZM55B5V6 is a 5.6V small package Zener diode
which can be used to remove voltage spike in cell phone design. The schematic is shown in below:
IN
= V
OUT(NOMINAL)
6
4
2
0
2
1
0
Input
Vcc
BZM55B5V6
+ 0.5V or 2.5V (whichever is greater), C
Time(10μs/div)
Start Up
1uF
Control
V
V
C
I
IN
OUT
IN
LOAD
= 5V
= C
= 2.5V
= 1mA
C
1
OUT
1
= 1μF
IN
IN
EN
3
= 1µF, C
SG2002
9
OUT
GND
2
= 1µF, C
BP/FP
BP
4
= 0.01µF, T
0.01uF
V
OUT
BUS
A
pin of USB interface when changer
5
= +25℃, unless otherwise noted.
C
2
4.7uF
SG2002/A
V
OUT