STM32L476 with custom segment LCD aka LCD glass aka Passive LCD

[Silas Valera]

Posted on July 02, 2017 at 23:38

Hello,

I have an application where I need the following:

1. Lowest possible power conusmption - in any mode run/standby/sleep - it is a battery powered application

2. The controller also includes segment LCD driver - driving up to min 64 segments

3. The controller also keeps the segment LCD live (no turning off the LCD) in sleep/standby mode 

Refering to the reference manual / data sheet for STM32L476, I found that this is a suitable controller I can use for my application.:

Q1. Has anyone any experience using STM32L4 in application for driving segment LCD? Can anyone please help me with any example / document?  

Q2. Further for the segment LCD, how does the common and segment pins layout work?

Any primer or document will be really helpful and very much appreciated..

Thanks in advance!

best

Silas  

#segment-lcd

[Silas Valera]

Posted on July 07, 2017 at 03:07

I am really so surprised  No one has done this before???!!  

[waclawek.jan]

Posted on July 07, 2017 at 23:45

The

http://www.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-eval-tools/stm32-mcu-eval-tools/stm32-mcu-discovery-kits/32l476gdiscovery.html

  may be a good starting point.

JW

[Imen.D]

Posted on July 11, 2017 at 17:49

Hello,

You may have a look to the LCD example available within STM32CubeL4 at this path:

STM32Cube_FW_L4_V1.8.1\Projects\STM32L476G_EVAL\Examples\LCD\LCD_SegmentsDrive

Regards

Imen

[Silas Valera]

Posted on July 24, 2017 at 00:33

Thanks Imen

I have actually moved away from that hardware design for the following reasons: Most of the the time STM32L4 will be in the sleep mode to conserve battery power. But the segment LCD display must stay ON all the time. I am not sure if the STM32L4 would still be driving the segment LCD and there by keeping the display ON even in the sleep mode.

I changed my design to use dedicated segment LCD driver chip PCF85176 which has I2C interface and ultra low power - draws only 3.5uA at 3V. With this set up STM32L4 can go to sleep mode without any display issues. 

Thanks !

Silas

[Abhishek Gupta]

Can Anyone share me how to drive the Custom LCD glass with STM32L0

[waclawek.jan]

LCD controller in the 'L0 is almost the same as in 'L4 , so you can start off the mentioned 'L4 Disco and its support material.

JW

[Abhishek Gupta]

Can anyone tell me what is the procedure of driving the lcd glass from either Stm32L0 or from STM32L4.

Since I am new in driving the Customize LCD glass so if there is any procedure than please share with me.

[waclawek.jan]

Download CubeL4 https://my.st.com/content/my_st_com/en/products/embedded-software/mcus-embedded-software/stm32-embedded-software/stm32cube-mcu-packages/stm32cubel4.html and look into [STM32Cube_FW_L4_Vx.x.x]\Drivers\BSP\STM32L476G-Discovery\stm32l476g_discovery_glass_lcd.c/.h, used by [STM32Cube_FW_L4_Vx.x.x]\Projects\STM32L476G-Discovery\Demonstrations\

[EDIT]

There's a LCD "glass" also on the https://www.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-eval-tools/stm32-mcu-eval-tools/stm32-mcu-eval-boards/stm32l073z-eval.html so you can look at examples in CubeL0 e.g. [STM32Cube_FW_L0_Vx.x.x]\Projects\STM32L073Z_EVAL\Examples\LCD\ .

I guess CubeMX will generate some code for the 'L0 LCD too, but I don't use CubeMX.

JW