PSAS/ ChargerIcResearchLv2

Lithium Ion Battery Charging ICs

Up: AvionicsPowerSystemLv2
Xref: BatteryPackLv2, Lv2PowerUsage, BatteryPack


  1. Recharges a 4 cell Li Ion pack (14.4V nominal, 16.8V max)
  2. Minimal parts count - and especially no weird resistor needed
  3. Minimum design time on circuit - i.e., clear application notes
  4. Vaguely modern - no "crufty" chips
  5. Small footprint

So far:

Linear Technology LTC4006:

This looks pretty good. We can also combine it with the LTC4412 "ideal diode" - it replaces a BASD (big ass schottkey diode) with a SOT23-6 IC (using only 11uA) and a MOSFET... which with a 0.01 ohm MOSFET saves us 0.3V drop * 4A - 4A^2 * 0.01 ohm = 1.0 watts!!!


Maxim equivalent: the MAX745 -

Battery fuel gage:

Linear Technology LT1513:

One of the pros of this part is its ability to boost its input voltage to provide a higher charging voltage. However, the data sheet indicates that at higher voltages the charging current of the LT1513 drops. Charging a cell at 16 volts, for example, the LT1513 can only provide 1 amp. In our situation this means it would take about five hours to charge the currently planned battery pack for the LV2 rocket payload. A closer to ideal charging chip would provide boost capability from, say, 18 VDC out given 12 VDC supply at 4A. We'll look a little longer, but probably won't find a chip that meets these specifications.

Other chips:


Interesting but possibly not applicable: a smart battery charger that DOESN'T NEED a host to operate! That's very, very interesting... we could use a smart battery with very little impact on ourselves - let the battery charge itself and then add charging software later. For example, a Dell 7000/7500 uses a 14.8 V 5.1 Ah smart battery... we could plug that into this smart charger and everthing might just "work".... uh huh, sure.