dell battery charging system for d5xx and d6xx laptops
The Dell Latitude D610 battery charging system used in a wide range of DELL laptops has caused quite a bit of frustration among it's customers. Top ranked is the "AC Power adapter not recognized" warning with DELL D620 laptop batteries not being charged. This alone has triggered a quest for information in many Internet forums mainly because DELL has not come forward with a reasonable explanation into the cause(s) of the problem. So here's info about the architecture and a bit of background of the dell d630 battery charging system used in DELL laptops.
The Smart Battery System
Based on the schematics of the DELL D610 Latitude, DELL has chosen to adopt theSmart Battery System architecture. The system is apparently introduced by Intel and Duracell for accurate power management for applications running on rechargeable dell d500 batteries. The initiative has it's own forum with a list of implementors on which DELL, among several chip manufacturers, is listed as the sole end-user / consumer system manufacturer. It's seems a bit odd, because most likely there are more laptop manufacturers who have used the Smart Battery System idea.
The Smart Battery System itself seems like a plausible concept and it appears the supporters have invested quite a bit to get the concept implemented. Also Maxim is part if the implementors which also produced the ID chip in the DELL AC Adapter. Page 9 of theSmart Battery System Specification V1.1 - December 1998 shows the block diagram of the battery charging system found in the schematics of the DELL D610 nattery. Most strikingly, the 1-Wire communication line with the AC - DC Adapter is not mentioned. It seems DELL has decided to walk alone on this. It doesn't sound like a smart thing to do, as the consequences already have shown.
Most components in the Smart Battery System are System Management Bus - SMBUS connected, the communication system invented by Intel® Corporation in 1995.
Quite a sophisticated bunch to charge 6 Li-Ion Dell Latitude D830 battery pack. Now the SMSC LPC47N354 - MacAllen III - Ultra IO controller is quite a chip. Unfortunately there's little public information available but it seems this chip executes POST and BIOS functions using a 8051 based micro controller. The latter is a highly popular multi-purpose embedded CPU capable of doing quite a bit of work in the lower dungeons of the D610 laptop.
The Smart Battery Host, the SMSC LPC47N354 - MacAllen III, can talk "1-wire" with the DELL AC Adapter. The Smart Battery Host initiates battery charging over the SMBUS after finding a valid AC adapter.
The Smart Battery Charger, the Maxim MAX1535B , is in control of the method of charging while the micro controller inside the battery merely executes the SMBUS charging commands.
DELL Standalone laptop battery charger and DELL Media bay batteries
DELL Media bay laptop battery - replaces the DVD or CDROM player
Standalone laptop battery charger for DELL laptop batteries.
Based on the above what are the possibilities of getting a Dell Latitude D600 Laptop battery charged using an DELL Adapter with a dead ID chip inside using only a software solution?
A few options;
Change the DELL BIOS / Controller firmware to disable the ID chip check
Getting access to the SMBUS and initiate Dell Latitude D800 battery charging through 8051 based routines
At this point in time both are not simple exercises and require quite a bit if knowledge and skills to accomplish the task. Nonetheless it's an interesting task - who knows what comes to surface after a little bit of thought?
Now - starting with an interesting observation:
How can a powered down DELL D610 detect the AC Adapter?
It must be through embedded 80x51 software executed by the SMSC LPC47N354 - MacAllen III - Ultra IO controller once the AC adapter is connected.
