Hi guys,
I've been working with this for a while now, and somehow I don't seem to have it working right. Please see attachment for the schematic of what I want to do. What I have is a 4.8V (4 x AA batteries - rated at 2600mAh each from Gold Peak, I've also attached the data sheet on these). The batteries seem to charge fine but when I use them again, the batteries don't last long at all, at least not as long as if they were brand new..I reckon I must have messed up the batteries from doing different trials.
Based on the equations provided on the data sheet, I calculated my "Ifast" current flowing to the battery to charge them at 867mA (This is 2600mAh/3 hrs = 867mA).
My R1 = ((minimum wallcube Voltage - 5V)/5mA) = 1.4kΩ. So, I'm using a power supply I got and so I don't know what they mean by minimum wall cube voltage but I just assume it's the voltage that is just applied to it, in this case, 12V. I'm applying 12V because I've got a wall adapter I want to use for this application, but don't want to cut the cable and put it in my breadboard, hence the power supply.
Rsense = .25V/867mA = .30Ω
The PGM# pins are based upon tables provided:
PGM0 = V+ (Using 4 AA battery cells)
PGM1 = BATT- (Using 4AA battery cells)
PGM2 = BATT- (264minute timeout and voltage drop termination enabled)
PGM3 = BATT- (C/2 trickle charge)
I'd really appreciate any help on this matter and thanks in advance!
--EDIT--
Forgot to add data sheet of MAX712..
http://datasheets.maxim-ic.com/en/ds/MAX712-MAX713.pdf
I've been working with this for a while now, and somehow I don't seem to have it working right. Please see attachment for the schematic of what I want to do. What I have is a 4.8V (4 x AA batteries - rated at 2600mAh each from Gold Peak, I've also attached the data sheet on these). The batteries seem to charge fine but when I use them again, the batteries don't last long at all, at least not as long as if they were brand new..I reckon I must have messed up the batteries from doing different trials.
Based on the equations provided on the data sheet, I calculated my "Ifast" current flowing to the battery to charge them at 867mA (This is 2600mAh/3 hrs = 867mA).
My R1 = ((minimum wallcube Voltage - 5V)/5mA) = 1.4kΩ. So, I'm using a power supply I got and so I don't know what they mean by minimum wall cube voltage but I just assume it's the voltage that is just applied to it, in this case, 12V. I'm applying 12V because I've got a wall adapter I want to use for this application, but don't want to cut the cable and put it in my breadboard, hence the power supply.
Rsense = .25V/867mA = .30Ω
The PGM# pins are based upon tables provided:
PGM0 = V+ (Using 4 AA battery cells)
PGM1 = BATT- (Using 4AA battery cells)
PGM2 = BATT- (264minute timeout and voltage drop termination enabled)
PGM3 = BATT- (C/2 trickle charge)
I'd really appreciate any help on this matter and thanks in advance!
--EDIT--
Forgot to add data sheet of MAX712..
http://datasheets.maxim-ic.com/en/ds/MAX712-MAX713.pdf
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