LTC4015_15 Datasheet, PDF (42/76 Pages) Linear Technology – Multichemistry Buck Battery Charger Controller with Digital Telemetry System

LTC4015
Operation
put is 5V and is supplying 42mA to the gate drivers, the
junction temperature rises to only 82°C:
T_J = 70°C + [(35V)(4mA)+(5V)(42mA)](34°C/W)
= 82°C
If DRV_CC is powered from an external LDO, the LDO should
be powered from V_SYS and its output must be less than
5.5V. In this case, DRV_CC should not be tied to INTV_CC.
Sequencing is also important, if DRV_CC is not tied to INTV_CC,
DRV_CC should not be applied until INTV_CC has reached 3V
to ensure the gate drivers are held off.
Die Temperature Sensor
The LTC4015 has an integrated die temperature sensor. It
is monitored by the ADC and is digitized to the DIE_TEMP
register. An alarm may be set on die temperature by setting
the DIE_TEMP_LO_ALERT_LIMIT and/or DIE_TEMP_HI_
ALERT_LIMIT registers and enabling the alarms in the
EN_LIMIT_ALERTS register.
INTV_CC and DRV_CC UVLO
Internal undervoltage lockout circuits monitor both the
INTV_CC and DRV_CC pins. The switching controller is kept
off until INTV_CC rises above 4.3V and DRV_CC is above
4.2V. Hysteresis on the UVLOs turn off the controller if
either INTV_CC falls below 4V or DRV_CC falls below 3.9V.
Charging is not enabled until V_IN is 200mV above the bat-
tery voltage. Charging is disabled when V_IN falls to within
100mV of the battery voltage.
Input Overvoltage Protection
The LTC4015 has overvoltage detection on its input. If
V_IN exceeds 38.6V, the switching controller will hold both
switches off. The controller will resume switching if V_IN
falls below 37.2V.
4015f
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For more information www.linear.com/LTC4015