RT9527 RICHTEK [Richtek Technology Corporation], RT9527 Datasheet - Page 3

• Manufacturer Part Number: RT9527
• Description: Single Cell Li-Ion Battery Charger with Adjustable Charging Current for Portable Applications
• Manufacturer: RICHTEK [Richtek Technology Corporation]

Operation
The RT9527 is a Li-ion charger that can support the input
voltage range from 4.4V to 6V. It provides a wide fast-
charge current setting ranging from 10mA up to 600mA.
Change Current Setting
The charging current is adjustable via an external resistor
between the ISET and GND pin.
UVLO
If the input voltage (VIN ) is lower than the threshold voltage
V
is larger than V
OVP
If the input voltage (VIN) is higher than the threshold voltage
V
will stop charging until VIN is below V
Switch Well
The switch well will choose the highest voltage between
VIN and BAT to prevent the power switch from damage.
Sleep Mode
When the voltage difference between VIN and BAT is under
V
power consumption.
Copyright
DS9527-00 May 2012
UVLO
OVP
OS_L
, the internal OVP signal will go high and the charger
, the charger will enter sleep mode to save the system
− ΔV
©
2012 Richtek Technology Corporation. All rights reserved.
UVLO
UVLO
, the charger will stop charging until VIN
.
OVP
− ΔV
OVP
.
CC/CV/TR Multi Loop Controller
There are constant current loop, constant voltage loop and
thermal regulation loop to control the charging current.
Too Hot or Too Cold
The temperature sense input TS pin can be connected a
thermistor to determine whether the battery is too hot or
too cold for charging operation. If the battery's temperature
is out of range, charging is paused until it re-enters the
valid range.
PGOOD
The PGOOD is an open-drain output used to indicate the
input voltage status. PGOOD will assert low when VIN is
in the proper working range.
CHG
The CHG pin is an open-drain output. CHG will assert low
when the charger starts to charge the battery and become
high impedance when the termination current is reached.
TIMER
The charger contains the safety timer. When the charging
time is longer than t
in the fast-charge mode, time fault happens. Then, the
charger will be turned off and the CHG pin will become
high impedance.
is a registered trademark of Richtek Technology Corporation.
PCHG
in the pre-charge mode or t
RT9527
www.richtek.com
FCHG
3