LCD 16x2 3.3V  - Page 1
Forum section: electronics / general

author: SPRX
author_rank: Regular Contributor
timestamp: June 05, 2013, 11:30:26 am
content: I am chasing 3.3v 16x2 LCD for my project prototype for a reasonable cost, (as I am planning to make about 50 units initially if all goes well). 3.3v version of LCDs seems fairly expensive compared to its 5v counterpart.Could anyone tell about a fairly reasonable source for this beast

author: mariush
author_rank: Super Contributor
timestamp: June 05, 2013, 01:43:40 pm
content: http://www.newhavendisplay.com/nhd0420azflgbw3v3-p-2003.html4x20 for 6$ on sale.a 5v version is 4$ on sale :http://www.newhavendisplay.com/nhd0420dznswbbwrev0-p-5210.html

author: Mr Smiley
author_rank: Frequent Contributor
timestamp: June 05, 2013, 03:57:45 pm
content: Or see Dave's Friday fundamentals, using a charge pump to power 1602 lcd modules

author: SPRX
author_rank: Regular Contributor
timestamp: June 06, 2013, 02:24:04 am
content: Quote from: mariush on June 05, 2013, 01:43:40 pmThanks mariush, seems a good deal and will try.Quote from: Mr Smiley on June 05, 2013, 03:57:45 pmThanks Mr Smiley, I saw this, but is this a common practice to drive a LCD ? Interented to see common practices for LCDs on a low voltage hand held devices.

author: marshallh
author_rank: Unknown
timestamp: June 06, 2013, 02:24:55 am
content: You can just run 3.3v I/O into the 5v lines. As long as its one way.Bet the actual logic will run fine on 3.3 also. May have to tweak for contrast.

author: SPRX
author_rank: Regular Contributor
timestamp: June 06, 2013, 05:44:39 am
content: Quote from: marshallh on June 06, 2013, 02:24:55 amThanks, I tried the 5v LCD modules I have on my hand with my 3.3v PIC 24fj128 microcontroller directly, but until you provide 5V on the Vdd, LCD is not happy, and mostly showing garbage.Any suggestions please

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: June 06, 2013, 06:42:18 am
content: Have you tried “1602 3.3v” on eBay?

author: ElektroQuark
author_rank: Unknown
timestamp: June 06, 2013, 06:50:27 am
content: Quote from: mariush on June 05, 2013, 01:43:40 pmCould not find shipping cost without register (I Hate this).

author: komet
author_rank: Unknown
timestamp: June 06, 2013, 07:21:09 am
content: I believe that this is 3.3V-compatibleeBay auction: #220868669255The S6A0069 is certainly a 3.3V chip, but you might want to confirm with the seller. I bought some but they've not arrived yet, so I can't tell you for sure.

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: June 06, 2013, 07:26:23 am
content: Quote from: komet on June 06, 2013, 07:21:09 amHmm...it says Vss and Vdd =5V in the description...

author: poorchava
author_rank: Super Contributor
timestamp: June 06, 2013, 07:27:06 am
content: 5V LCD modules are problematic to drive directly from LVCMOS logic, because they typically have VIH defined as 0.7*VCC which in this case equals 3.5V.Standard TC7660 charge pump should be enough.You can also use dedicated level shifters. I'm using SN74LVC4245A from TI (bought a bunch some time ago, they are like 0.40 € in retail in Poland), although probably there are 20 other 74xx chips that you can use for that.edit:a second thought: maybe you can try old mobile phone GLCD? Like the ones from nokia 3310. They are dirt cheap on ebay and the topic is well understood on every microcontroller-related forums. And is has a serial interface which saves some pins in comparison to 16x2 displays.

author: komet
author_rank: Unknown
timestamp: June 06, 2013, 07:27:53 am
content: Quote from: iloveelectronics on June 06, 2013, 07:26:23 amYeah, sorry, I'm probably being an idiot. Still, it's not uncommon for chinese sellers to have incorrect descriptions...

author: SPRX
author_rank: Regular Contributor
timestamp: June 06, 2013, 11:32:40 am
content: Thank you for all replies.Nokia 5110/5146 seems like a good candidate for the application, with few code and PCD design change.I will also test 5v module with a charge pump, as most of you seems comfortable with it, and probably easier to do with it. Any one of you had used TEXAS REG710NA-5/250 (3.25V to 5v) or similar ?