Sharp LM320191 | Industrial-Grade Monochrome FSTN Display for High-Clarity HMI
The Sharp LM320191 is a 5.7-inch FSTN (Film-compensated Super-twisted Nematic) monochrome display, engineered for applications where data clarity, reliability, and operational longevity are non-negotiable. Developed by industry pioneer Sharp, this QVGA (320x240) panel delivers exceptional performance in a robust package, making it a strategic choice for new designs and legacy system maintenance alike.
- Unmatched Readability: Leverages advanced FSTN technology to produce a high-contrast (22:1 typical) black-and-white image, ensuring critical information is legible under a variety of industrial lighting conditions.
- Proven Backlight Reliability: Features a long-life CCFL (Cold Cathode Fluorescent Lamp) backlight system, prized in industrial settings for its stable brightness and predictable performance over tens of thousands of hours.
- Simplified Integration: An integrated display controller and a standard parallel data interface reduce the engineering effort required to incorporate it into control systems, test equipment, and other specialized machinery.
- Low Power Profile: Optimized for efficiency, the display consumes a mere 1.2W (typical), making it ideal for portable or power-sensitive applications where every milliwatt counts.
Application Scenarios & Engineering Value
The Sharp LM320191 is not just a component; it's a problem-solver. Its specific characteristics provide tangible advantages in demanding environments:
- Industrial Control Panels & PLC Interfaces: In manufacturing and process control, ambiguity can lead to errors. This display's crisp, high-contrast text and graphics are perfect for presenting vital machine parameters, status alerts, and diagnostic codes without the distraction or potential misinterpretation of color.
- Test and Measurement Equipment: For benchtop oscilloscopes, network analyzers, or portable field instruments, the LM320191 provides a clear, power-efficient readout. Its proven design ensures it can withstand the rigors of a lab or field environment while preserving battery life.
- Legacy System MRO (Maintenance, Repair, and Overhaul): This display serves as a reliable, form-fit-function replacement for aging or failed monochrome LCDs in long-lifecycle equipment. It allows engineering teams to extend the operational life of valuable assets without a complete system redesign.
- Medical Instrumentation: Ideal for devices like infusion pumps or basic patient monitors where the primary need is the unambiguous display of numerical data and simple waveforms. Its reliability is paramount in such mission-critical applications.
Technical Deep Dive: The Enduring Merit of FSTN and CCFL
While many modern designs default to color, the technology inside the Sharp LM320191 is a deliberate choice for performance. Unlike many color TFT-LCDs, FSTN technology is hyper-optimized for monochrome performance. The addition of a retardation film layer (the "F" in FSTN) corrects optical dispersion, dramatically improving the viewing angle and creating a truly black-and-white display with a superior contrast ratio.
Similarly, the CCFL backlight provides a highly uniform, stable light source known for its robustness and gradual, predictable end-of-life dimming curve. This allows for scheduled maintenance, a critical advantage over the sudden failure modes that can sometimes occur with other backlight technologies in harsh conditions.
Key Parameter Overview
The following table outlines the core specifications for system designers. For comprehensive electrical characteristics, timing diagrams, and mechanical drawings, please refer to the official datasheet.
| Parameter | Value |
|---|---|
| Display Technology | 5.7" FSTN Monochrome LCD |
| Resolution | 320 x 240 Pixels (QVGA) |
| Active Area | 115.17(W) x 86.37(H) mm |
| Outline Dimensions | 167.0(W) x 109.0(H) x 10.0(D) mm |
| Brightness (Typical) | 130 cd/m² |
| Contrast Ratio (Typical) | 22:1 |
| Backlight System | Single CCFL, Edge-lit |
| Operating Temperature | 0°C to +45°C |
For detailed engineering data, Download the Sharp LM32019T Datasheet (a close variant with representative specifications).
Frequently Asked Questions for Design Engineers
Q1: Is the LM320191 a suitable upgrade for an older STN display?
A: Yes. In most cases, its FSTN technology offers a significant upgrade in contrast and viewing angle over older STN or TN panels. The standard QVGA resolution and parallel interface make it a strong candidate for drop-in replacement, though verification of the controller command set and physical mounting is always recommended.
Q2: What are the power supply considerations for the CCFL backlight?
A: The CCFL tube requires a dedicated inverter module to generate the high-voltage AC needed for ignition and operation. This is a critical design consideration for new systems. For retrofits where a CCFL was already in use, this often simplifies the replacement process as the existing power infrastructure can be leveraged.
Choosing the Sharp LM320191 is a strategic decision for projects prioritizing clarity, reliability, and total cost of ownership over color. For help with your specific application or to explore our full range of industrial LCD displays, please contact our technical team.
