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MFJ-4416B Super Battery Booster
Instruction and Technical Manual
9
THEORY OF OPERATION
consisting of rectifier diodes D2 and D3 that sample the RF being fed to the unit. When
the RF is sensed then the switch consisting of Q7 and Q6 turn on to take the Enable Input
of the regulator IC low turning it on. The last section of the MFJ-4416B is the Low
Voltage Detection circuit. This circuit uses on of three selectable voltage dividing
resistors to sample the input voltage. When the voltage drops below a pre-determined
level it takes the comparator’s output high. If the jumper is placed on the Latching
Header then this high level is then inverted and fed back into the input of the comparator
which holds the comparators output high. Reset of the low voltage disconnect is
accomplished by disconnecting the input voltage.
Typical efficiency at +13.8VDC output and +12VDC output are shown in the tables
below.
Typical Efficiency – Output set to +13.8V
Vin Iin Vout Iout Eff
13.0 27.8A 13.8V 24.00 92%
12.0V 30A 13.8V 24.00 90%
12.5V 20A 13.8V 17A 94%
12.5V 25A 13.8V 21A 91%
11.5V 23A 13.8V 17A 91%
11.5V 27A 13.8V 21A 93%
*11.2V
28A 13.8V
21A 92%
10.5V 26.5A 13.8V 17A 90%
10.0V 20.2A 13.8V 13.8A 94%
*Limited by the input 30-amp fuse
Typical Efficiency – Output set to +12V
Vin Iin Vout Iout Eff
14V 21.5A 12.9V 22.5A 96%
13V 22.5V 12.1V 21A 87%
12V 24.5 12V 21A 86%
11V 27.9A
12V 21A 82%
10V 24.9A
12V 18A 87%
