aoz9004d Alpha & Omega Semiconductor, aoz9004d Datasheet - Page 13

• Manufacturer Part Number: aoz9004d
• Description: Single-cell Battery Protection Ic
• Manufacturer: Alpha & Omega Semiconductor

Applications Information
A low-pass filter formed by R1 and C1 reduces supply
voltage fluctuation on the VDD pin. R1 also provides ESD
protection and serves as an current-limiting resistor in the
event of charger reverse connection. The supply current
of AOZ9004D has to flow through R1, so a small R1
should be chosen to guarantee detection accuracy of
VDD voltage. Choose a resistor value between 100Ω
and 330Ω for R1. Choose the value of C1 to be 0.022µF
or higher. Both R1 and C1 should be placed as close as
possible to AOZ9004D to minimize parasitic effect.
Table 3. External Components Selection Range
Rev. 1.0 October 2006
Designator
C1
R1
R2
when a charger is reversely connected
Provide ESD protection and limit current when a charger is reversely
connected
Reduce supply voltage fluctuation, provide ESD protection, and limit current
Reduce supply voltage fluctuation
Lithium Polymer
Lithium-Ion or
Single-Cell
Battery
Figure 5. AOZ9004D Applications Circuit
Purpose
www.aosmd.com
C1
0.1µF
AOZ9004D
VDD
R2 provides ESD protection and serve as a current-
limiting resistor in the event of charger reverse
connection. A large value resistor should be chosen to
limit power consumption during this condition. However,
an extremely large value of R2, of course, will cause
inaccuracy of VM pin voltage detection. Choose a
resistor value between 300Ω and 4kΩ for R2.
VSS
4
1
R1
200Ω
OUTM
VM
3
2
R2
2kΩ
0.022µF
300Ω
Min.
EB+
EB-
100Ω
0.1µF
Typ.
2kΩ
220Ω
AOZ9004D
Page 13 of 16
Max.
1.0µF
4kΩ
330Ω