Newhaven Display Forum

Newhaven Products => TFTs => Topic started by: mike_s on January 06, 2019, 12:36:45 PM

Title: Active Lo/Active Hi signals for these TFTs?
Post by: mike_s on January 06, 2019, 12:36:45 PM
Hi Everyone,

I'm currently working on my initial setup with this TFT: NHD-5.0-800480TF-ATXL-CTP

The datasheets don't specifically call out or mark the signals as Active Hi or Active Lo... these are the signals for this panel:

Pin No.    Symbol    External Connection    Function Description       
1    LED-    LED Power Supply    Ground for Backlight    
2    LED+    LED Power Supply    Backlight Power Supply (60mA @ ~19.2V)       
3    GND    Power Supply    Ground       
4    VDD    Power Supply    Power supply for LCD and logic (3.3V)       
5-12    [R0-R7]    MPU    Red Data Signals       
13-20    [G0-G7]    MPU    Green Data Signals       
21-28    [B0-B7]    MPU    Blue Data Signals       
29    GND    Power Supply    Ground       
30    CLKIN    MPU    Clock for input data (Rising Edge)       
31    STBYB    MPU    1: Normal Operation;0: Standby Mode       
32    HSD    MPU    Line synchronization signal      ****   PULL-UP?  ****
33    VSD    MPU    Frame synchronization signal      ****  PULL-UP? ****
34    DEN    MPU    Data Enable signal       
35    NC    -    No Connect       
36    GND    Power Supply    Ground       
37    XR    -    No Connect       
38    YD    -    No Connect       
39    XL    -    No Connect       
40    YU    -    No Connect    

Pin No.    Symbol    External Connection    Function Description       
1    VCC    Power Supply    Power supply for logic (3.0V)       
2    GND    Power Supply    Ground       
3    SCL    MPU    Serial I2C Clock (Requires pull-up resistor)       
4    SDA    MPU    Serial I2C Data (Requires pull-up resistor)       
5    /INT    MPU    Interrupt signal from touch panel module to host        ****   PULL-UP  ****
6    /RESET    MPU    Active LOW Reset signal                                        ****   PULL-UP  ****

From the timing diagrams, It seems that ONLY  VSD, HSD, INT, & RESET are active LO signals?  all the rest are Active HI, ie default state is pulled down..

Can anyone verify that this is correct, ONLY VSD, HSD, INT, & RESET need to be pulled-up?

Thanks so much,

- Mike