APL3207
Function Description (Cont.)
Charge Status Output (STAT) (Cont.)
STAT
Output
Mode
VIN
VBATT
VIN>VUVLO
Low
Charge mode
&
VIN>VBATT+
VBATT<4.2V
VASD
High
Shutdown mode VIN>VUVLO
&
-
Standby mode VIN>VBATT+ VBATT>4.2V
VASD
VIN<VUVLO
Sleep mode
or
Battery is
VIN<VBATT+ connected
VASD
Table1. STAT Pin Summary
VSET
0.1V<VSET<1.2V
VSET>1.2V
-
-
LDO Regulator
The APL3207 has been built in a regulator whose output
voltage is fixed at 3.3V. When the system is powered by a
battery, the regulator is fully powered by the battery;
however, when the battery is charged, the regulator input
is switched to the USB or adapter (by using external circuit)
and powered by the USB or adapter, which reduces the
charging time.
Regulator Current Limit and Short Circuit
The APL3207 includes a current limit circuitry for LDO
regulator. The current limit circuitry senses the output
current and limits the maximum output current to prevent
the APL 3207 and external loads frorm being damaged.
The point where limitation occurs is ILDO=300mA (typical).
When the output is shortened to the ground, the regulator
reduces the current-limit threshold down to 50mA (typical).
The output can be shortened to the ground for an indefi-
nite amount of time without damaging the part.
Regulator Thermal Protection
The LDO regulator has a built-in thermal protection
function. When the junction temperature exceeds +135oC,
the thermal sensor generates a logic signal to turn off the
regulator which makes the die cool down. When the junc-
tion temperature cools down by 20oC, the thermal sen-
sor turns the regulator on again, resulting in a pulsed
output during continuous thermal protection. Thermal pro-
tection is designed to protect the IC in the event of fault
conditions.
Copyright © ANPEC Electronics Corp.
13
Rev. A.3 - Sep., 2012
www.anpec.com.tw