LTC4015_15 Datasheet, PDF (64/76 Pages) Linear Technology – Multichemistry Buck Battery Charger Controller with Digital Telemetry System

LTC4015
DETAILED Register Descriptions
MAX_CV_TIME (Sub-Address 0x1D, Bits 15:0, Fixed: R, Programmable: R/W)
For lithium chemistries, this 16-bit word sets the termination time limit at one second per count. If the charger is in
the CV state for MAX_CV_TIME seconds, timer termination occurs. The actual timer value is reported in CV_TIMER.
See the section Timer Termination for more information. The default setting is four hours (14,400) for Li- Ion batteries
and one hour (3,600) for LiFePO₄ batteries. For lead-acid batteries, MAX_CV_TIME is ignored.
MAX_ABSORB_TIME (Sub-Address 0x2B, Bits 15:0, Fixed: R, Programmable: R/W)
For LiFePO₄ and lead-acid batteries, this 16-bit word sets an upper limit on the time (at one second per count) that
the battery can be in the absorb charge phase. The actual timer value is reported in ABSORB_TIMER. See the sections
LiFePO₄ Absorb Charge and Lead-Acid Absorb Charge. For Li-Ion batteries, MAX_ABSORB_TIME is ignored.
EQUALIZE_TIME (Sub-Address 0x2D, Bits 15:0, Fixed: R, Programmable: R/W)
For lead-acid batteries, this 16-bit word sets the time (at one second per count) for the equalization charge phase. For
lead-acid batteries, the default setting is 3600 seconds. See the section Lead-Acid Equalization Charge. For lithium
chemistries, EQUALIZE_TIME is ignored.
MAX_CHARGE_TIME (Sub-Address 0x1E, Bits 15:0, Fixed: R, Programmable: R/W)
For lithium chemistries, this 16-bit word sets the max_charge_time fault detection time at one second per count. The
default setting is 18.2 hours (65535). If the MAX_CHARGE_TIMER exceeds MAX_CHARGE_TIME during charging, a
max charge time fault occurs. See the section Max Charge Time Fault for more information. For lead-acid batteries,
MAX_CHARGE_TIME is ignored.
LIFEP04_RECHARGE_THRESHOLD (Sub-Address 0x2E, Bits 15:0, Fixed: R, Programmable: R/W)
In LiFePO₄ programmable mode only, this 16 bit two's complement word sets the recharge threshold, where the
recharge threshold/cell = [LiFePO4_RECHARGE_THRESHOLD] • 192.264µV. Default is 0x4410 which is 3.35V/cell.
JEITA_Tn (Sub-Address 0x1F Through 0x24, Bits 15:0, Fixed: R, Programmable: R/W)
(n = 1,2,3,4,5,6)
For lithium chemistries, these six 16-bit words set the JEITA temperature region break points T1 – T6, and have the
same format as NTC_RATIO. The temperatures are based on the thermistor reading from the measurement system.
Recall that the thermistor has a negative temperature coefficient so JEITA_T1, representing colder temperatures, will
have the highest value and JEITA_T6, representing warmer temperatures, will have the lowest value. See the section
JEITA Temperature Qualified Charging. JEITA_Tn are ignored for lead-acid batteries or if en_jeita=0.
Programming of JEITA Values
REGION 1
REGION 2
REGION 3
REGION 4
REGION 5
REGION 6
REGION 7
[JEITA_T1]
[JEITA_T2]
[JEITA_T3 ]
[JEITA_T4]
[JEITA_T5]
[JEITA_T6]
CHARGER
OFF
icharge_jeita_2
vcharge_jeita_2
icharge_jeita_3
vcharge_jeita_3
icharge_jeita_4
vcharge_jeita_4
icharge_jeita_5
vcharge_jeita_5
icharge_jeita_6 CHARGER
vcharge_jeita_6 ^OFF
VCHARGE_JEITA_6_5 (Sub-Address 0x25, Bits 9:0, Fixed: R, Programmable: R/W),
VCHARGE_JEITA_4_3_2 (Sub-Address 0x26, Bits 14:0, Fixed: R, Programmable: R/W)
For lithium chemistries, these two registers contain the charge voltage settings to be used in the JEITA voltage vs
temperature profile. VCHARGE_JEITA_6_5 contains two bit packed values, vcharge_jeita_6 (bits 9:5) and vcharge_jeita_5
4015f
64
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