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Switching Battery Charger with L296 - del20031

This circuit is derived from an application note of L296, It is a Power Switching Regulator from ST Micro. This technology saves power means less heat and smaller size PCB. 

Lighting and Power control Automation

L296 is a switch mode power controller here. In this NTE327 or 2N5038 is used to boost the current output. This transistor is both high current and fast switching. U1A, LM358 measures the load current by reading the voltage across shunt R6 and compared to a current limit setting at R14 using U1B to give a load current control. R7-R8 give a voltage feedback for voltage limit.

U1A is wired as a diffrential amplifier and U1B a High Gain Comparator. C4 and C5 are parallel for lower ESR.

Switching Battery
                        Charger with L296
PNG-Schematic     PDF-Circuit
Switching Battery Charger with L296 - del20031
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Use MFR 1% for all Resistors, 33E means 33 ohms, 22K means 22 kilo ohms, 1M is 1 megohm. 10T tp means ten turn trimpot. "Analog Ground" and "Digital Ground" must be linked at power supply only, avoid loops, let grounds radiate from a ground plane. Unused inputs of logic and opamps pull up or down to avoid oscillations and noise. Connect supply of all chips if not mentioned.

Battery Management and Supply Design

Put a 104 CD cap (0.1uF Ceramic Disc) for all ICs from positive to negative close to IC, even if omitted in circuit. Opamps on dual supply rails two caps. Circuit is a design, some of my designs are not yet tested, use only for Education and Information. Use it as an idea for study dont expect it to work out of the box. BUX39 can also be tried for Q1, we need 15A+ -- 100V -- <1uS.  L1 = 220uH 15A, 50T turns 0.5mm Cu Wire on Hi-Freq Torroid. 10A Current carrying tracks must be reinforced by copper braids or wires.