L6924D STMicroelectronics, L6924D Datasheet - Page 27

• 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

L6924D
8.2
8.3
Battery absence detection
This feature provides a battery absent detection scheme to detect the removal or the
insertion of the battery. If the battery is removed, the charge current falls below the I
At the end of the de-glitch time, a detection current I
output for a time of T
V
checked to see if the voltage on the output goes higher than V
mV). If the battery voltage changes from V
it means that no battery is connected to the charger. The T
Equation 26
Figure 22. Battery absent detection flow chart
Status pins
To indicate various charger status conditions, there are two open-collector output pins, ST1
and ST2. These status pins can be used either to drive status LEDs, connected to an
external power source, by a resistor, or to communicate to a host processor. These pins
must never be connected to the V
PRETH
YES
, a current equal to I
Detect High Absent
Detect Low Absent
BATTERY
ABSENT
V
V
V
V
PRETH
>
>
BAT
BAT
RCH
NO
DETECT
NO
YES
DETECT
. The device checks the voltage at the output. If it is below the
Doc ID 11908 Rev 9
DETECT LOW ABSENT = a I
DETECT HIGH ABSENT = a I
T
I
SINK
DET
IN
= I
PRE CHARGE
is injected in the output capacitor for a T
= 100ms (Typ.)
T
when it exceeds their absolute value (6 V).
Application information: monitoring and protection
INJ
DETECT
= 1mA (Typ.)
FAST CHARGE
PRETH
=
54×
T
MAXCH
to V
10
DETECT
ABS
3
SINK
INJ
and vice versa in a T
is injected for a T
, equal to 1 mA, is sunk from the
DETECT
is sunk for a T
ABS
(the value is V
is expressed by:
DET
DET
from the battery
in the battery
DETECT
DETECT
OPRGTH
, and it is
ENDTH
time,
27/38
-50
.