We have purchased the demo board DC2134A for the LTC 4020 but it’s operation doesn’t make sense.
While the battery status is in float mode (battery fully charged - RED LED is ON and Green is OFF ) and there is input power available to the charger we are noticing that the battery is STILL sourcing the load even though the charger is powered up.
The demo board, DC2134A, is spec’ed as having a MAX output of 8 AMPS from 21 to 28 volts. Our load is set to 8 Ohms ( about 3 amps) which is nowhere near the max current capability of the charger output. Our questions is this, Why then would the charger allow the battery to source the load (FET on ) if the load doesn’t require the battery?
We have meters connected to the demo board showing the following :
Iout 3 Amps
Battery Voltage 23.49
Battery Current ( supping the load through the FET ) 2 Amps
Batteries are 8 AH rating - We have two 12 volt ones setup in series.
Jumper is set to LEAD ACID
Are we missing something here or are we misinterpreting the indented purpose of the DEMO board or chip design ? Any help would be greatly appreciated.