Automatic Charger for Battery Operated Hi-Fi Preamps - For those who want the cleanest possible DC for sensitive preamps, battery power is ideal. At last, remembering to turn the charger back on is no longer a problem! This project is one for the experimenter, but as shown will work extremely well. The sensing circuit can be made so sensitive that a load of only 2.5mA is enough for the circuit to detect, and disconnect the charger. __ Designed by Rod Elliott ESP Automatic Trickle Charger - Scroll down to find this circuit. Here is the schematic for the automatic charger I have been using for my kids' battery cars. The charger is a small molded unit that probably doesn't supply more than an amp and this circuit would have trouble with much more. No current limit is provided by this circuit __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Battery charger - This project is not so important for those who ride a car every day. In my case, a car is not used every day. In that case, the voltage of a battery is falling and a car sometimes cannot be put into operation __ Designed by Seiichi Inoue
Bidirectional Power Inverter - 08/02/01 EDN-Design Ideas If you want to swap charge in either direction between unevenly loaded positive and negative battery buses, you need an inverting dc transformer. One implementation is the symmetrical flyback converter shown in Figure 1. The circuit Design by Tom Napier, North Wales, PA
Car Battery Charger - quickly and easily charge most any lead acid battery, automatically turns charging off when ready. __ Designed by Aaron Cake
Car-Battery Charger - If Built and Setup Correctly, It will safely charge at 10 Amps and Automatically Regulate down to a Trickle Charge. This Charger Can't be used as a Power Supply, Without having a battery in place. The Battery MUST be Connected to get power out. __ Designed by G.L. Chemelec
Charge indicator gauges lead-acid batteries - 05/27/99 EDN-Design Ideas Although rechargeable, sealed lead-acid cells are uncommon in portable applications, they are a good choice for standby applications, such as emergency lighting and burglar alarms. A key advantagePDF has several circuits, please scroll to find this one. Design by Fran Hoffart, Linear Technology Corp, Milpitas, CA
Charge Monitor for 12 Volt Rechargeable Lead Acid Battery - A battery is a vital element of any battery-backed system. In many cases battery is more expensive than system it is backing up. Hence we need to adopt all practical measures to conserve battery life. As per manufacturer's data sheets, a 12V rechargeable lead-acid battery should be operated within 10. IV and 13.8V. When battery charges higher than 13.8V
Charger Extends Lead-Acid-Battery Life - 12/01/11 EDN-Design Ideas A circuit that properly charges sealed lead-acid batteries ensures long, trouble-free service. A circuit that properly charges sealed lead-acid batteries ensures long, trouble-free service. Fig 1 is one such circuit; it provIdeas the correct temperature-compensated charge voltage for batteries having from one to as many as 12 cells, regardless of the number of cells being charged. Design by Fran Hoffart, National Semiconductor Corp, Santa Clara, CA
Charger for Deep-Cycle 12V Batteries, Pt 2 - Second article has the full construction and set-up details for this new high-performance charger.__ SiliconChip
Charger for Deep-Cycle 12V Batteries, Pt.1 - Thats not a charger...this is a charger! If you want to change deep-cycle 12V batteries correctly, this 16.6A unit is the way to go.__ SiliconChip
Charger for Gel Lead Acid Batteries - This high-performance circuit first quickly starts (Tony van Roon's and holds) the charge at 2 amp, but as the voltage rises the current will consequently decrease. When the current falls below 150mA, the charger automatically switches to a lower 'Float' voltage to prevent overcharging. At the point that a full charge is reached, Q1 will bias and the LED will light. __ Designed by Tony van Roon VA3AVR
Charger Selects between Full & Trickle Charge - 06/18/98 EDN-Design Ideas The circuit in Figure 1 charges a lead-acid battery at full charge voltage while monitoring the charge current. When the charge current decays to approximately 0.1C, where C is the capacity of the battery, the charger automatically switches to a lower trickle-charge voltageFile has several circuits, please scroll to this one Design by Ajmal Godil, Linear Technology Corp, Milpitas, CA
Circuit Charges Lead Acid Batteries - 02/03/97 EDN-Design Ideas The circuit in Figure 1 charges lead-acid batteries in the conventional way. A current-limited power supply maintains a constant voltage across the battery (2.4V/cell or so, as specified by the battery manufacturer until Design by Dana Davis, Maxim Integrated Products, Sunnyvale, CA
Circuit Charges Lead Acid Batteries - Integrated App Note 621 -- A flyback converter implements a current-limited power supply to charge lead-acid batteries. The MAX668 PPM controller limits the output current, and the flyback transformer provides isolation and flexibility for input voltages both above and below the battery voltage. The MAX4375 current-sense amplifier monitors the charging current and uses its internal comparator that below a designed threshold the flyback converter can switch to a lower charging voltage for trickle-charge mode. The circuit shown in Figure 1 charges lead-acid batteries in the conventional way: A current-limited power supply maintains a constant voltage across the battery (approximately 2.4V/cell, as specified by the battery manufacturer) until the charging current decreases below a current threshold defined by the capacity of the battery. __ APP 621 Aug 26, 2011
Emergency Lamp & Turning Indicator - White LEDs are replacing the conventional incandescent and fluorescent bulbs due to their high power efficiency and low operating voltage. These can be utilised optimally for emergency lamp and vehicle turning __ Electronics Projects for You
Experimental Alternator Controller - Here is the schematic for the automatic charger I have been using for my kids' battery cars. The charger is a small molded unit that probably doesn't supply more than an amp and this circuit would have trouble with much more. No current limit is provided by this circuitit relies on the charger for that. The circuit could be modified to provide more current by scroll down to find this one __ Contact: Charles Wenzel of Wenzel Associates, Inc.
Gel cell Battery Charger - Recently, a fellow amateur was looking for a gel cell charger which would first charge at a fixed rate and then later switch to a trickle charge when the cell was fully charged. After reviewing several catalogs and web sites, the MAX712 IC was discovered. This IC meets all the requirements for almost any type of battery charging system. The circuit in Figure 1 was designed specifically for 12 volt gel cells __ Designed by Radio Amateur Society of Norwich
Gel-Cell Charger I - This high-performance circuit first quickly starts (Tony van Roon's and holds) the charge at 2 amp, but as the voltage rises the current will consequently decrease. When the current falls below 150mA, the charger automatically switches to a lower 'Float' voltage to prevent overcharging. At the point that a full charge is reached, Q1 will bias and the LED will light. __ Designed by Tony van Roon VA3AVR
Gel-Cell Charger II - This circuit needs a regulated 10V-DC front end capable of supplying 2 Amps. Starts the charge cycle at 240mA and at full charge switches automatically to a float condition (trickle charge) of 12mA. __ Designed by Tony van Roon VA3AVR
Gell Cell Lead Acid Battery Charger - This high-performance circuit first quickly starts (Tony van Roon's and holds) the charge at 2 amp, but as the voltage rises the current will consequently decrease. When the current falls below 150mA, the charger automatically switches to a lower 'Float' voltage to prevent overcharging. At the point that a full charge is reached, Q1 will bias and the LED will light. __ Designed by Tony van Roon VA3AVR
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