{"text_format":"3","workbook":"xls","n_sheets":3,"sheets":["Dual Step Charger","Charger with bias trickle","Large series of cells"],"not_rendered":{"images":4,"external_links":1,"defined_names":1},"read":"whole","date_system":"1900","formulas":"cached_only"}

{"sheet":"Dual Step Charger","index":0,"n_rows":28,"n_cols":4,"rows_kept":28,"flags":["formulas_cached_only"]}
["Number of cells, N",12]
["Cell Charge voltage",2.4,"Volts/cell"]
["Cell Float voltage",2.25,"Volts/cell"]
["Cell Charge threshold voltage",1.7,"Volts/cell"]
["Battery Capacity (C)",1.2,"amp hours"]
["Maximum Battery Charge Rate",14.15,"% of C"]
[]
[{"$nulls":3}," "]
[]
["Over Charge Voltage","Voc",{"v":28.799999999999997,"d":"28.80"},"Volts"]
["Float Voltage","Vf",{"v":27,"d":"27.00"},"Volts"]
["Transition Voltage from State 1 to State 2","V12",{"v":27.359999999999996,"d":"27.36"},"Volts"]
["Transition Voltage from State 3 to State 1","V31",{"v":24.3,"d":"24.30"},"Volts"]
["Maximum Charge Current","Imax",{"v":0.1698,"d":"0.170"},"Amps"]
["Over charge terminate threshold","Ioct",{"v":0.016980000000000002,"d":"0.017"},"Amps"]
["Reference Voltage","Vref",2.3,"Volts"]
[]
["Notes"]
["Over Charge Voltage is around 2.4 volts/cell"]
["Float Voltage is 2.25 to 2.30 volts/cell"]
["Charge threshold voltage is typically 1.7 volts/cell"]
["Imax is bulk charge rate; e.g., C/4, range from C/20 to C/3"]
[]
["Ib (ranges from 50 to 100 uA)",100,"uA"]
["Ra",{"v":247,"d":"247.0"},"K ohms"]
["Rb",{"v":23,"d":"23.0"},"K ohms"]
["Rc",{"v":315.61111111111194,"d":"315.6"},"K ohms"]
["Rs",{"v":1.4723203769140165,"d":"1.47"},"ohms"]

{"sheet":"Charger with bias trickle","index":1,"n_rows":55,"n_cols":10,"rows_kept":55,"flags":["formulas_cached_only"]}
[]
[]
[null,"From Unitrode Application note SLUS186 - September 1996"]
[null,"Input Data:"]
[null,"Number of cells","N",12]
[null,"Charge voltage",null,2.4,"Volts/cell"]
[null,"Float voltage",null,2.25,"Volts/cell"]
[null,"Charge threshold voltage",null,1.7,"Volts/cell"]
[null,"Battery Capacity (C)",null,1.2,"amp hours"]
[null,"Maximum Battery Charge Rate",null,14.15,"% of C"]
[null,"Trickle Current Ratio",null,0.5,"% of C"]
[null,"Input Voltage","Vin",36,"Volts"]
[null,"Reference Voltage","Vref",2.3,"Volts"]
[null,"Transistor b, minimum","b",50]
[null,"Transistor maximum current","Icmax",1,"Amp  "]
[null,"Divider current.  Recommend 50uA to 100 uA","Id",50,"uA","when at Vf"]
[]
[null,"Calculations:"]
[null,"Charge Threshold Voltage","Vt",{"v":20.4,"d":"20.40"},"Volts","N*Chrg threshold voltage"]
[null,"Over Charge Voltage","Voc",{"v":28.799999999999997,"d":"28.80"},"Volts","N*Charge Voltage"]
[null,"Float Voltage","Vf",{"v":27,"d":"27.00"},"Volts","N*Float Voltage"]
[null,"Transition Voltage from State 1 to State 2","V12",27.359999999999996,"Volts","0.95Voc"]
[null,"Transition Voltage from State 3 to State 1","V31",{"v":24.3,"d":"24.30"},"Volts","0.9Vf"]
[null,"Maximum charge current","Imax",0.1698,"Amps","C*Max Charge Rate"]
[null,"Over charge terminate threshold","Ioct",0.016980000000000002,"Amps","Imax/10"]
[null,"Trickle Current","It",0.006,"Amps","C*Trickle Charge Ratio"]
[]
[]
[null,null,"Rc",{"v":46,"d":"46.0"},"Kohms","= Vref / Id",{"$nulls":3}," "]
[null,null,"Rsum",{"v":494,"d":"494.0"},"Kohms","Ra + Rb = (Vf - Vref) / Id"]
[null,null,"Rd",{"v":631.2222222222231,"d":"631.2"},"Kohms","Rd = 2.3VRsum/(Voc - Vf)"]
[null,null,"Rx",{"v":42.875471698113216,"d":"42.9"},"Kohms","Rx = Rc||Rd"]
[null,null,"Ra",{"v":476.3453940066592,"d":"476.3"},"Kohms","Ra = (Rsum + Rx) (1 - 2.3V/Vt)"]
[null,null,"Rb",{"v":17.654605993340795,"d":"17.7"},"Kohms","Rb = Rsum - Ra"]
[null,null,"Rs",{"v":1.4723203769140165,"d":"1.5"},"ohms","Rs = 0.25V/Imax"]
[null,null,"Rt",{"v":2.1833333333333336,"d":"2.18"},"Kohms","Rt = (Vin - Vt - 2.5V) / It"]
[null,null,"PD of Rt",{"v":0.0786,"d":"0.079"},"Watts","(Vin - Vt - 2.5)^2 / Rt"]
[null,null,"Re",{"v":1689.9999999999998,"d":"1690.0"},"ohms","(Vin - 2.2)/(Icmax/b)"]
[null,null,"PD of Driver",{"v":119.85930954096001,"d":"119.9"},"mw","(Vin - Vbe)*Ib - Re* Ib^2"]
[]
[null,"Notes"]
[null,"Battery over charge voltage is around 2.4 to 2.7 volts/cell"]
[null,"Battery float voltage is 2.25 to 2.30 volts/cell"]
[null,"Battery charge threshold voltage is typically 1.3 to 1.7 volts/cell"]
[null,"Imax is bulk charge rate; e.g., C/4, range from C/20 to C/3"]
[null,"Battery temperature range is nominally 0 to +50 degrees C"]
[null,"Battery self discharge rate is typically 2 to 5 % a month."]
[null,"Diode D1 prevents reverse current flow."]
[]
[null,"Equations for Ra, Rb, Rc, and Rd do not account for the saturation voltage of the power indicator and state level switches. "]
[null,"Vce sat @ 50 uA = 50 mV max, 30 mV typical."]
[]
[]
[]
[{"$nulls":8}," "]

{"sheet":"Large series of cells","index":2,"n_rows":29,"n_cols":4,"rows_kept":29,"flags":["formulas_cached_only"]}
["Number of cells",12]
["Charge voltage",2.4,"Volts/cell"]
["Float voltage",2.25,"Volts/cell"]
["Charge threshold voltage",1.7,"Volts/cell"]
["Battery Capacity (C)",1.2,"amp hours"]
["Maximum Battery Charge Rate",14.15,"% of C"]
["Holding Current Rate",0.5,"% of C"]
[]
["Input Voltage","Vin",{"v":36,"d":"36.00"},"Volts"]
["Holding Current ( C x Holding Curent Rate)","Ih",0.006,"Amps"]
["Float Voltage","VF",{"v":27,"d":"27.00"},"Volts"]
["Transition Voltage from State 1 to State 2","V12",{"v":31.04695,"d":"31.05"},"Volts"]
["Transition Voltage from State 2 to State 1","V21",{"v":24.3,"d":"24.30"},"Volts"]
["Maximum Charge Current (C x Max Chg Rate)","Imax",0.1698,"Amps"]
[]
["Reference Voltage","Vref",2.3,"Volts"]
["Notes"]
["Over Charge Voltage is around 2.4 volts/cell"]
["Float Voltage is 2.25 to 2.30 volts/cell"]
["Charge threshold voltage is typically 1.7 volts/cell"]
["Imax is bulk charge rate; e.g., C/4, range from C/20 to C/3"]
[]
["Ic(range from 50 to 100uA)",100,"uA"]
["Ra",{"v":247,"d":"247.00"},"K ohms"]
["Rc",{"v":23,"d":"23.00"},"K ohms"]
["Rd",{"v":100,"d":"100.00"},"K ohms"]
["Rsm",{"v":1.4723203769140165,"d":"1.472"},"ohms"]
["Rsh",{"v":4.166666666666667,"d":"4.167"},"ohms"]
["Re",{"v":825.5083333333334,"d":"825.5"},"ohms"]