Nokia LCD types

There is plenty of info on the net on driving these neat LCDs, however there are 2 types of controller chip used, Philips & Epson. Each uses a different command set (Nokia phones auto-detect and support both types).

I'm planning to use this display in a forthcoming product, and bought a few from various sources to figure out ways to identify which chip each uses - there are a number of 'knock-off' suppliers, so there are a fair few different physical appearances.

When buying from phone parts dealers, they are unlikely to know which driver chip their LCDs have, do I'd suggest you ask them for a photo of the actual units.

The most obvious way to identify the controller type is the size of the driver chip at the top. Large = Epson, Small = Philips. If anyone has found an example that contradicts this assumption, please let me know. Update - the Epson clone controller on recent Sparkfun LCDs is a similar size to the Philips chip, so chip size is no longer a good indication.

If you have any pics of different units, AND KNOW FOR CERTAIN WHICH CONTROLLER THEY USE ( i.e. by testing), please email photos of front & back as below with supplier details if possible.

Note that a few of the units below have had the connector support frame chopped down by me to fit my PCB - all displays originally came WITH the support frame. Some may also have had some tape removed at the top to allow the connector flexi to be moved.

The main difference between the Epson 15G00 and 15G10 is that the latter supports a 2 byte->1 pixel 16 bit mode. Note that there are now LCDs (possibly using an Epson clone controller) that don't apear to support the old 3 byte-> 2 pixel modes.

Note on recent (end 2007) Sparkfun Stock - they have changed supplier, and the new ones have a couple of subtle differences. I found the following changes when getting my old code to run with them :

1) Do NOT use NOP commands. Early code examples for this LCD sent a NOP after at the end of a data block - (possibly to make it recover if the wrong number of data bytes was sent) This NOP causes problems with the new controller, and is not necessary on the older ones.

2) Only relevant if using 16 bit mode : The 3 byte/2 pixel 16 bit mode (DATCTL with P3=2) does not appear to be supported by the new controller. The 2 byte/1 pixel mode (DATCTL with P3=4), as documented on Loren Blaney's page and in the Epson S1D15G10 datasheet seems to work fine.

For the backlight LED supply from a 5V rail, one small & cheap solution is the Texas TPS60403 - this is a +5 to -5 charge pump converter. As the backlight in the LCD module is isolated from the driver, you can connect the backlight between +5V and the -5V output of the charge-pump, via a 150R resistor. Not especially efficient (50mA at 5V for 20mA backlight drive), but very small (sot23-5) and pretty cheap - just the chip and 3 0805 1uf ceramic caps, no inductor.

Back	Front	Supplier/type
		EPSON Ebay seller Cellulardeals22 (peeling tape at top was me...)
		Sparkfun Electronics ( Old stock - green PCB) EPSON
		Sparkfun Electronics - New stock ( Brown PCB) EPSON clone - chip is much smaller. See note above re. compatibility.
		Ebay UK seller Bargens123 EPSON


		Ebay UK ( can't remember who) PHILIPS
		Ebay UK Seller Nokiafone101 "New type 3100" came with keypad PHILIPS
		Embedded Artists LCD/Bluetooth demo board PHILIPS ( possibly Philips compatible LDS176) Both of the Philips units above give a strange colour map and mirrored image on the EA board - possibly some subtle difference in the LDS chip. My only reason for thinking this LCD uses the LDS chip is that there is a reference to it somewhere in the EA docs.
		From a real Nokia Phone. Interestingly this one displays correctly on the EA board - maybe it's the 2 'Philips' ones above that have the LDS, or even a different chip...? PHILIPS
		Thanks to Bertrand Achard for this info : LCD number 1: seems to use a PCF8833 chip because it was made prior to 2004 and at this time the LDS chip wasn't available, and I have used it in a project using the PCF8833 datasheet to make it work (and it worked). It is from Iyoung from Taiwan, a cellphone LCD supplier, but as stated it was bought prior to 2004 so it is unlikely that this model is still available from them. This LCD is interesting because we know for sure which controller it has ! LCD number 2: when connected to a board that uses the LCD number 1, the colors are inverted and the screen is mirrored. As a result I think that this LCD uses the LDS chip, but this is not certain because the controller is behind the glass whereas the controller was on the glass on the LCD 1. Origin unknown. I would like to add some additionnal info - I found an easy way to distinguish between a LDS176 and a PCF8833 display. The LDS176 controller has a "12bits type B" mode that doesn't exist with PCF8833. Otherwise, this LCD works the same way than LCD number 1, apart from two inversion: a mirror inversion, and a RGB/BGR inversion, which are all corrected at initialization by modifying two bits in the registers.