The LTC4425EMSE#PBF is a linear SuperCap Charger with current-limited ideal diode and V/I monitor. This constant-current/constant-voltage linear charger is designed to charge a 2-cell supercap stack from either a Li-ion/Polymer battery, an USB port. The part operates as an ideal diode with an extremely low 50mR on-resistance making it suitable for high peak-power/low average power applications. The LTC4425 charges the output capacitors to an externally programmed output voltage in LDO mode at a constant charge current or to VIN in normal mode with a smart charge current profile to limit the inrush current until the VIN to VOUT differential is less than 250mV. In addition the LTC4425 can be set to clamp the output voltage to 4.9 or 5.4V. Charge current (VOUT current limit) is programmed by connecting a resistor between PROG and GND. The voltage on the PROG pin represents the current flowing from VIN to VOUT for current monitoring.
● 50mR Ideal diode from VIN to VOUT
● Smart charge current profile limits inrush current
● Internal cell balancer (no external resistors)
● Programmable output voltage (LDO mode)
● Programmable VIN to VOUT current limit
● Continuous monitoring of VIN to VOUT current via PROG Pin
● Low quiescent current (20µA)
● VIN power fail, PGOOD indicator
● 2.45/2.7V Cell protection shunts (4.9/5.4V SuperCap maximum top-off voltage)
● 3A Peak current limit, thermal limiting
