Introduction: SHARP LQ5AW136 TFT Display
I got a Sharp LQ5AW136 TFT display from an old car CD, TO interface it with ESP32 using the Fabgl library to drive the display.
Volkswagen VW Radio Navigation System MFD, Golf, 3b0035191d
this display uses different voltages. +5V -5V , 2.16 , 8 and 12V for the backlight inverter .
I cut the original display connector from the Car CD, and I did use it in the PCB board to interface with the display, I have to use load termination to lower the signal amplitude because the SHARP display requires it 0.7V for red green, and blue. I cut the VGA board from an old TV motherboard, I did use it as load termination.
Supplies
1.ESP32
2. SHARP LQ5AW136 TFT DISPLAY
3. DC TO DC Buck converter 3
4. Dual voltage buck converter 1
5. Breakout board for the display connections
6. Load termination breakout board
7. old laptop power supply 19 V
8. Two potentiometers, one for backlight, the second for color intensity
9. backlight driver circuit
Attachments
Step 1: SHARP AVTFT
SHARP AVTFT displays are generally meant to be
driven with either a NTSC Composite Video or with discrete
RGB Video signals. SHARP’s AVTFTs have video
compatible inputs that enable easy interfacing to a camcorder,
a VCR, or the video output from a CCD camera.
Most AVTFTs have two video input channels. One channel
may be an NTSC Composite input and the other will
be discrete RGB Video input. An example of this video
input configuration is the LQ056A3CH01.
The LQ5AW116 is a dual video input channel
AVTFT with discrete RGB inputs. It has a composite
video input, but the display electronics merely use this
input to strip off the sync information, disregarding the
video content of the composite signal.
The LQ5AW116 was designed for discrete RGB
video sources. It does not have an onboard video
decoder. It requires an external video decoder IC like the
SHARP IR3Y18A to make it compatible with NTSC
video. However, if the user does not have a video source
and wants to drive the LQ5AW116 with a flap panel
video controller like a C&T, this paper will demonstrate a
method of interfacing to the C&T 65545 video controller
to drive either of the panel’s RGB input channels.
Step 2: LQ5AW136 OPERATION
LQ5AW136 OPERATION
The LQ5AW116 is an AVTFT (Audio Visual Thin
Film Transistor) LCD. It can display one of two video
input channels by making pin 7, VSW = HIGH
(channel 1) or VSW = LOW (channel 2). The display
can generate an LCD pixel clock internally or it can use
an external clock depending on the setting of CLCK
input. If the video signal input is NTSC decoded RGB,
then CLCK = HIGH and an internal PLL will generate a
pixel clock that is phase locked to the sync input. By
doing this, pin 22 (CLK), pin 1 (HSYNC) and pin 2
(VSYNC) become outputs. If an RGB video signal is
available and the user would like to control the LCD
timing, set CLCK = LOW, making CLK, HSYNC, and
VSYNC inputs.
Pin 8 (SAM) determines the external clock sampling
mode. In Independent Data Sampling mode
(pin 8 = HIGH), external clock (18.2 MHz to 19.6 MHz)
is three times faster than in Simultaneous mode
(pin 8 = LOW) and video data is sampled sequentially
(first red, then green, and then blue). In Simultaneous
mode, all three video inputs are sampled at the same
point in time with a slower clock (6.8 MHz to 7.6 MHz).
