On Fri, 3 Nov 2000, Don Papp wrote: > On Thu, 2 Nov 2000, Doug Sutherland wrote: > > > 2) I am taking a serious look at a charging system > > that would allow me to charge while running the > > system. I want my wearable to operate like a > > laptop, plug it in and it charges. I also want > > to be able to monitor the voltages, eventually > > tweak the linux APM bios to read that info. I > > have found someone willing to cook something > > up for me, but it's not a guarantee yet so I > > will update you on that when it materializes. > > > Doug, you may wish to check out the power supply at www.mpja.com > (ASTEC LAPTOP SUPPLY). I have used several myself, and they work fine. > > http://www.mpja.com/1-ac-dc-power-supply.htm > > Specs are below: notice some handy features like the inline > charging, digital outputs for some useful states, a digital as well as > wired input for shutdown, and so forth. You can use any voltage source > with it and get the +/-5, +/-12 out but the onboard charging (which I have > not tried) works only with Ni-Cads. > Here are more complete specs on the AA90304: 43W Power Conversion Module for Portable Computers Features -------- - Designed for laptop computer applications - High effeciency -- 80% minimum - Extremely samll size -- 120mm x 45mm x 20mm - Multimode switching battery charger - Adaptor input reversed polarity protection - Output short circuit protection - Multi-level battery low warning - Fully regulated +5V and +12V outputs - Battery full signal - Remote convertor disable - Battery-in-use signal - Power OK signal - -12V output for RS232 - -26V output for LCD - -5V output for modem - Light weight (110gm) Description ----------- The AA90304 is designed specifically to handle the power conversion requirements in a portable personal computer. It consists of a DC-DC convertor section and a battery charger section. The DC-DC convertor section generates 5 regulated DC outputs, +5V, +12V, -12V, -5V and -26V. The +5V and +12V outputs have tight line and load regulation specifications so that surge loads on +5V and +12V will not affect one another, or the backlight that runs on +12V. An unusually high effeciency of 80% minimizes the generation of heat and conserves batty power, extending battery life by as much as 15% compared to conventional DC-DC convertors used for portable computers. The battery charger is a highly effecient and intelligent switchmode charger. When the computer is not running and the battery is not full, the battery is charged with the full rapid charge current of 1.7A to 2.0A. When the computer is switched on, in order to minimize the loading of the AC adaptor and the generation of heat inside the computer, the charging current is reduced to the quick charge level of 0.6A. The charger detects the charging state of the battery. When the battery is fully charged, a temperature sensor located at the battery pack provides battery temperature information to the charger. The temperature sensor can be either a temperature sensing EC such as the LM34 or a temperature actuated switch. The charger will declare battery full wehn battery temperature reaches 43 deg C according to the LM34 or if the temperature actuated switch flips from short to open. When the DC-DC convertor is running off battery, two battery low signals are generated depending on the amount of energy left. Batt L1 indicates that battery is running low and not much more energy is left. Batt L2 indicates that battery is too low and battery life could be affected if the computer is not shut down immediately. Batt L1 usually turns on a warning LED and Batt L2 is usually hard wired to the computer to initiate a shutdown sequence, independent of user control. A Batt-In-Use signal informs the computer that the AC Adaptor is not plugged in. It can be used to initiate battery conservation prodecures such as timing out of hard disks when the hard disk has not been accessed for an extended period of time. A POK (Power OK) signal ensures the computer will power up reset properly. A Convertor Disable input allows the computer to shut down itself. When directly connected to the Batt L2 signal, the convertor will shut itself down when battery voltage falls below a dangerous threshold. Extensive use of surface mount technology packs a lot of power and features inn an unusually small package of 120mm L x 45mm W x 20mm H (4.72in L x 1.77in W x 0.79in H). Electrical Characteristics -------------------------- (Unless otherwise specified, all parameters are specified at 25 deg C ambient temp) Power Input: >From Adaptor - floating 18V +/-0.5V 55W >From Battery - 11V to 16V 4.1A max at 11V Convertor Outputs: +5V 3.5A (4.2A surge) +12V 1.1A (1.4A surge) -12V 40mA -26V 40mA -5V 40mA Charger Output: Output Voltage 11V to 16V Rapid Charge 1.7A - 2.0A Quick Charge 0.5A - 0.7A Trickle Charge 50mA - 150mA Absolute Maximum Ratings: Adaptor input voltage 0V to +20V Battery input voltage 0V to +20V Opterating heatsink temperature 0 to 85 deg C Storage temperature -40 to +105 deg C Input Protection: Adaptor will shut down before output exceeds 80W Battery protected by internal fuse in DC-DC convertor DC-DC Convertor Outputs Nominal Output Voltage +5V +12V -12V -26V -5V Minimum load (A) 0.3 0.02 0.02 0 0 Maximum load (A) 3.5 1.1 0.04 0.04 0.04 Surge load (A) - 30 secs 4.2* 1.4* - - - Initial tolerance (+/-%) 2 2 10 25-30 10 Line/load regulation (+/-%) 2 2 10 25-30 10 Output ripple (mV pk-pk) 50 100 100 100 100 Efficiency at maximum load (including charger output) 80% minimum Quiescent Current (battery current drain when DC-DC convertor is disabled and Adaptor is not in use) < 100uA *Surge load can only be drawn from either one of the two outputs: +5V or +12V at any instant. Note: Battery must be connected all the time. Logic Level ----------- 1. Batt L1, Batt L2, Batt F, Batt in Use, POK min max unit VOH 4 5 V at Io = -10uA HOL 0 0.5 V at Io = 40uA 2. Power Disable min max unit VTH 3.5 5.0 V VIL 0 1.0 V IIH 8 10 uA at VI = 4V Output Signals -------------- POK - Active high with 100mS to 500mS delay after all rails are in regulation Batt L1 - Active high when battery is below 11.75V +/- 0.1V Batt L2 - Active high when battery is below 11.30V +/- 0.1V Batt-In-Use - Active high when Adaptor input is not more than two diode drops above battery input. Battery Full - Active low when Adaptor is in use and battery is full. Battery is considered full when a thermal switch connecting to +TS and -TS opens or the temperature sense inputs +TS and -TS have a voltage of >1.09V, indicating the temperature of the sonsor (for example, LM34) has exceeded 43 deg C. Charger will switch into Trickle mode when battery is full. Battery full state will only be reset by removal of Adaptor. Input and Controls ------------------ Power Disable - Turns off DC-DC convertor when pulled high momentarily. DC-DC convertor will remain off until the Power Switch is toggled off/on. +TS, -TS - Two wire battery temperature sense input. A termperature sensing IC such as LM34 or a temperature actuated switch embedded in the battery pack provides temperature information to these inputs. When the voltage across these two inputs exceeds 1.09V (due to output of LM234 or the opening of the temperature switch), Battery Full output is enabled and charge switches into Trickle Charge mode. SW1, SW2 - To be connected to a low current power switch. This switch breaks off the power for the control circuit of the DC-DC convertor so that it is effectively turned off. A high current switch for interrupting the input power for the DC-DC convertor is not necessary. Connector Pinouts ----------------- JST 6-Way Connector Pin Connection 1 -Batt 2 +Batt 3 +Temp Sense 4 -Temp Sense 5 -Adaptor 6 +Adaptor Molex 20-Pin Dual Row Header (Output Connector) Pin Connection 1 -5V 2 -26V 3 0V 4 0V 5 0V 6 0V 7 +12V 8 +12V 9 -12V 10 +5V 11 +5V 12 +5V 13 Batt L2 14 Batt L1 15 Batt F 16 POK 17 Batt-In-Use 18 Power Disable 19 SW1 20 SW2
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