L6924D STMicroelectronics, L6924D Datasheet - Page 12

• Manufacturer Part Number: L6924D
• Description: IC BATTERY CHARGER SYS 16-VFQFPN
• Manufacturer: STMicroelectronics

Specifications of L6924D

• Function: Charge Management
• Battery Type: Lithium-Ion (Li-Ion), Lithium-Polymer (Li-Pol)
• Voltage - Supply: 2.5 V ~ 12 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 16-VFQFN
• Product: Charge Management
• Output Current: 30 mA
• Operating Supply Voltage: 2.5 V to 12 V
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• For Use With: 497-8428 - BOARD EVAL CHARGER ST7260/L6924D497-8247 - BOARD EVAL FOR L6924UTR497-5504 - EVAL BOARD FOR L6924D
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Operation description
6.1
12/38
When the V
different functions:
●
●
Battery disconnection control is provided thanks to the differentiated sensing and forcing
output pins. A small current is sunk and forced through V
battery, the IC goes into a standby mode.
Figure 5
mA (R
Figure 5.
Linear mode
When operating in linear mode, the device works in a way similar to a linear regulator with a
constant current limit protection.
It charges the battery in three phases:
●
●
●
V
of the L6924D. If the battery voltage is lower than a set pre-charge voltage (V
pre-charge phase takes place. The battery is pre-charged with a low current I
(Chapter 7.2 on page
When the battery voltage goes higher than V
charge current I
Finally, when the battery voltage is close to the regulated output voltage V
4.2 V), the voltage regulation phase takes place and the charging current is reduced. The
ADP
0.50 0
0.45 0
0.40 0
0.35 0
0.30 0
0.25 0
0.20 0
0.15 0
0.10 0
0.05 0
0.00 0
If the voltage across V
notified by the status pin, but the charging process is not disabled. The charge process
ends when the maximum charging time expires.
If the voltage at V
Pre-charging current (“Pre-Charge” phase).
Constant current (“Fast-Charge” phase).
Constant voltage (“Voltage Regulation” phase).
is the output voltage of the upstream AC-DC adapter that is, in turn, the input voltage
PRG
0
shows the real charging profile of a Li-Ion battery, with a fast charge current of 450
= 26 kΩ),
PRE
Li-Ion charging profile
CHG
pin is not used to program the Pre-Charge voltage threshold, it has two
, set through an external resistor
2 00
17).
PRE
pin false under 0.5 V the timer is reset on the falling edge.
PRE
Doc ID 11908 Rev 9
pin is lower than 0.8 V, when I < I
400
C harging profile
Charging tim e (sec )
60 0
PRETH
, the battery is charged with the fast
(Chapter 7.4 on page
OUT
8 00
. If V
ENDTH
OSNS
10 00
, the end of charge is
doesn’t detect the
OPRGTH
18).
PRETH
PRE
Ichg
Vb att
1 200
(4.1 V or
), the
L6924D
4.50 0
4.00 0
3.50 0
3.00 0
2.50 0
2.00 0
1.50 0
1.00 0
0.50 0
0.00 0