Qdatasheet_Logo
Integrated circuits, Transistor, Semiconductors Search and Datasheet PDF Download Site

LTC4099 View Datasheet(PDF) - Linear Technology

Part Name
Description
MFG CO.
'LTC4099' PDF : 36 Pages View PDF
LTC4099
Operation
The battery charger current settings are decoded in
Table 3. The battery charger current settings are adjusted
by selecting one of the eight servo voltages for the PROG
pin. Recall that the programmed charge current is given
by the expression:
ICHG
=
VPROG
RPROG
• 1030
The default state for the battery charger current settings is
000, giving the lowest available servo voltage of 500mV.
The COVERX1 and COVERX0 bits are decoded in Table 4.
The C/x setting controls the PROG pin level that the
LTC4099’s C/x comparator uses to report full capacity
charge. For example, if the 100mV setting is chosen, then
the LTC4099 reports that its PROG pin voltage has fallen
Table 1. LTC4099 Input Data Bytes
SUB ADDRESS 0 SUB ADDRESS 1 SUB ADDRESS 2
COMMAND
REGISTER 0
COMMAND
REGISTER 1
IRQ MASK
REGISTER
Bit 7
ILIM2
TIMER2
USBGOOD
Bit 6
ILIM1
TIMER1
WALLGOOD
Bit 5
ILIM0
TIMER0
BADCELL
Bit 4
ICHARGE2
DISABLE_CHARGER THERMAL_ REG
Bit 3
ICHARGE1
ENABLE_ BATTERY_ THERMISTOR_
CONDITIONER
STATUS
Bit 2
ICHARGE0
Bit 1
COVERX1
Bit 0
COVERX0
VFLOAT = 4.2V
TREG = 85°C
Not Used
CHARGER_STATUS
Not Used
Not Used
Table 2. ILIM2 – ILIM0 Decode
USB INPUT CURRENT LIMIT SETTINGS
ILIM2
ILIM1
ILIM0
IUSB
0
0
0
100mA*
0
0
1
500mA
0
1
0
620mA
0
1
1
790mA
1
0
0
1000mA
1
0
1
1200mA
1
1
0
Suspend Low (500µA)
1
1
1
Suspend High (2.5mA)
*Default Setting
below 100mV. For the 50mV setting, LTC4099 reports
that its PROG pin voltage has fallen below 50mV. The C/x
settings are adjusted by comparing the PROG pin voltage
with the values shows in Table 4. The default value for the
C/x setting is 00, giving 100mV detection.
The second byte of data at sub address 0x01 controls the
three battery charger safety timer bits, TIMER2-TIMER0,
the DISABLE_CHARGER bit, the ENABLE_BATTERY_
CONDITIONER bit, the VFLOAT = 4.2V control bit and the
TREG = 85°C control bit.
The TIMER2–TIMER0 bits control the duration of the bat-
tery charger safety timer. The safety timer starts once the
LTC4099 reaches the 4.100V or the 4.200V float voltage.
As long as input power is available, charging will con-
tinue in float voltage mode until the safety timer expires.
Table 3. ICHARGE2 – ICHARGE0 Decode
BATTERY CHARGER CURRENT LIMIT SETTINGS
ICHARGE2 ICHARGE1 ICHARGE0
CHARGE CURRENT
VPROG
RPROG = 1.02k
0
0
0
500mV*
500mA
0
0
1
600mV
600mA
0
1
0
700mV
700mA
0
1
1
800mV
800mA
1
0
0
900mV
900mA
1
0
1
1000mV
1000mA
1
1
0
1100mV
1100mA
1
1
1
1200mV
1200mA
*Default Setting
Table 4. C/x Decode
C/x INDICATION SETTINGS
COVERX1 COVERX0 VPROG
0
0
100mV*
FULL CAPACITY CHARGE
INDICATION
RPROG = 1.02k
100mA*
0
1
50mV
50mA
1
0
200mV
200mA
1
1
500mV
500mA
*Default Setting
4099fd
23
Share Link: GO URL

All Rights Reserved © qdatasheet.com  [ Privacy Policy ] [ Contact Us ]