ISL6294 Intersil, ISL6294 Datasheet - Page 5

• Manufacturer Part Number: ISL6294
• Description: High Input Voltage Charger
• Manufacturer: Intersil

Description
The ISL6294 charges a Li-ion battery using a CC/CV profile.
The constant current I
R
4.2V. If the battery voltage is below a typical 2.55V trickle-
charge threshold, the ISL6294 charges the battery with a
trickle current of 19% of I
above the trickle charge threshold. Fast charge CC mode is
maintained at the rate determined by programming I
the cell voltage rises to 4.2V. When the battery voltage
IREF
GND
PPR
VIN
(See Figure 1) and the constant voltage is fixed at
EN
POR
REF
19%I
REF
is set with the external resistor
2.55V
CHG
4.2V
I
REF
REF
until the battery voltage rises
5
PRE
REG
TRICKLE
200K
CHG
V
VCC
REF
FIGURE 4. TYPICAL CHARGE PROFILE
V
OS
CC
FIGURE 3. BLOCK DIAGRAM
REF
until
ISL6294
BAT
INDICATION
I
MIN
reaches 4.2V, the charger enters a CV mode and regulates
the battery voltage at 4.2V to fully charge the battery without
the risk of over charge. Upon reaching an end-of-charge
(EOC) current, the charger indicates the charge completion
with the CHG pin, but the charger continues to output the
4.2V voltage. Figure 4 shows the typical charge waveforms
after the power is on.
The EOC current level IMIN is programmable with the
external resistor R
CHG
CHARGE
CURRENT
CONTROL
CHARGE
IMIN
VOLTAGE
CHARGE
CV
IREF
IMIN
EN
(See Figure 1). The CHG signal turns
VCC
76%I REF
TIME
V
115°C
REF
DIE
TEMP
February 18, 2005
BAT
FN9174.0