What is the point of this resistor network?

Your network seems to consist of a series / parallel combination of eight 27 Ω resistors that is equivalent to a single 54 Ω resistor. The significant thing is that these are surface mount and will be placed by machine.

Presumably eight are required for power handling. The circuit could have used one 54 Ω through-hole 1 W resistor but this would require an extra component and, probably, hand installation and soldering. With pick and place equipment this could be avoided for this component (although not for the caps, relay and MOSFETs) and possibly there were some savings by using resistors which had been bought in bulk for elsewhere in the circuit.

Another reason one might see series combinations is because of high voltage, such as dimmer-circuits, etc. The components may have a maximum voltage rating considerably less than the circuit voltage and this is solved by series connection of several resistors but that is not the problem in your application as it is low-voltage battery powered.


Since this is a low-voltage circuit, the reason is almost certainly to reduce the power dissipation in each resistor. The maximum power dissipation in the network is probably higher than the rated maximum dissipation for a single resistor, so they spread the power among 8 resistors...each resistor is only required to dissipate 1/8 of the total power.


Using resistor network instead of a single resistor is to increase power dissipation or maximal rated voltage of the single resistor.