12V 7.2AH SLA battery (6): UC2906 charger design

 Here is my third try at an SLA charger circuit.  It uses the UC2906/UC3906 smart charger IC as the charger controller.  The schematic of the test board is shown below.  The charger is going to be powered by an old discarded 19V laptop power supply.  Circuit description follows under the schematic.

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• The input power enters at J1 on the left. 
• Jumpers JP1 to JP3 and resistors R1 to R7 allow setting the current limit up to 1.75A in 0.125A increments. 
• LED1 to LED3 are used to display the state of the charger:  1) constant current state ,   2) overvoltage state, 3) float voltage state, or 4) trickle current state
• RA1, RB1, RC1, RD1, and RT3 are used to set the charge parameters according to the data sheet instructions:  overvoltage level, float voltage level, and trickle current.
• The power element is a TIP32C PNP transistor Q1
• The battery is connected at J2 on the right.

The diagram below is the layout for the test board: 

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The diagram below show a 3D rendering of the test board. 

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I am going to try etching a board using the toner method.  I've ordered some ferric chloride etchant and expect it to arrive on Friday.