feature

Dot Matrix Replacement HPDL-1414 Model Smart Alphanumeric Display Built-in RAM, ASCII Decoder and LED Driver Circuits 128 ASCII Character Sets Stackable on Ends Sorted by Luminous Intensity; Yellow and Green by Color Low Power and Sunlight Viewable AlGaAs Version Wide Viewing angle (typ. 50°)

illustrate

They are 3.7 mm (0.145 in) four-character 5 x 7-dot matrix display CMOS ICs driven by the vehicle. These monitors are pin for use with the HPDL-1414. The integrated circuit stores and decodes 7-bit ASCII data and displays a 5 x 7 font in an easy-to-read manner. Multiplexing and LED driver circuits are also included in the display, and fast setup and hold times allow it to interface with an approachable microprocessor. The address and data inputs can be connected directly to the microprocessor address and data. HDLX-1414 offers a larger character set than HPDL-1414. Lowercase special symbols are now laid out by 5 x 7 dot matrix characters. The difference between the daylight visible HDLS-1414 and the low power HDLU-1414 lies in the brightness level. The sun-visible version provides high-intensity characters in an internal setting. The lower power version uses the same LED technology but reduces the current through each LED to a much lower level and maintains an intensity equivalent to HDLO-1414.

Absolute Maximum Ratings

Supply Voltage, V DD to Ground [1] – 0.5 V to 7.0 V

Input voltage, any pin to ground –0.5V to 5V DD+0.5V

Free Air Operating Temperature Range, TA –40°C to +85°C

Storage temperature TS – 40 degrees Celsius to +100 degrees Celsius

Relative humidity (non-condensing) 85% wave solder temperature at CMOS integrated circuit junction temperature +65 degrees Celsius,

1.59 mm (0.063 in) below body at 250 degrees Celsius for 3 seconds

ESD classification, R=1.5 kΩ, C=100 pF class 1 (0-1999 V)

Note:

1. Maximum voltage without LED lighting.

Electrical/Optical Characteristics over Operating Temperature Range 4.5

notes:

1. V DD = 5.0 volts.

2. Average IDD measured at full brightness. Peak IDD = 28/15 x Average IDD (#).

3. I DD (#) max = 130 mA, 150 degrees Celsius IC junction temperature and V DD = 5.5 volts.

Optical characteristics at 25 degrees Celsius[1]V DD=5.0 V, full brightness

AC timing characteristics are too large

Temperature Range at V DD=4.5 V

notes:

1. Unless otherwise specified, tolerance on all dimensions is ±0.254 mm (0.010 in).

2. Dimensions are in millimeters (inches).

Show internal block diagram

Figure 2 shows the internal block diagram of the HDLX-1414 display. The CMOS integrated circuit is composed of 4×7 character RAM, 128 character ASCII decoder and its refresh necessary circuit synchronous decoding and four 5×7 dot matrix driving roles. Store four 7-bit ASCII words in character RAM. The IC reads the ASCII data and decodes it with a 128-character ASCII decoder. The decoder includes HPDL's 64 character set - 1414, 32 lowercase ASCII symbols and 32 foreign language symbols.

data input

Figure 1 shows the HDLX-1414 display. Address inputs A 0 and A 1 are used to select the digit position in the display. When both 0 and 1 are logic low, the data is loaded into the most appropriate role. Data inputs D 0–D 6 are used to load information into the display. Data is latched to the given rising edge of the character address WR signal. Data and address inputs must remain stable during write cycles to ensure that the correct data is stored on the display.

Electromechanical precautions

The HDLX-1414 is a 12-pin dip stackable to create any character array size. The monitor is designed to operate reliably at -40°C +85°C ambient temperature. The HDLX-1414 consists of die-connected and lead-connected 140 LEDs and a CMOS integrated circuit high temperature printed circuit. A polycarbonate lens is placed on the PC board to form a protective air gap LED wire connection. Backfilled epoxy environmentally sealed display packaging. This wrap construction makes the display highly resistant to temperature cycling and allows for wave welding.

Electrostatic discharge and latch-up

The input to protect the CMOS IC is an ESD input current latch. However, for best results, precautions should be taken with standard CMOS processing. Before using HDLX-1414 should be stored in anti-static tube or conductive material. A work area should be used when assembling ground conductors, and assemblers should wear conductive wrist straps. Outpatient laboratory synthetic material coatings should be avoided as they are prone to static electricity. Input current blocking can occur when the CMOS input is affected by a voltage grounded (V in V DD) and when strong current enters the input. To prevent input current latching and ESD damage, unused inputs should be grounded or grounded five. Voltage should not be applied to the input until V DD has turned on, and high transient input voltages should be eliminated.

Soldering Instructions The HDLX-1414 is compatible with both hand and wave soldering processes. Use of unclean flux is recommended. The polycarbonate lens above shows incompatibility with some fluxes and cleaners to resolve. Not recommended for use with heated terpenes, or propylene glycol solutions of monomethyl ether and monoethanolamine. For soldering and post-solder cleaning, see Application Note 1027, Soldering LED Components. Contrast Enhancement The purpose of contrast enhancement is to provide good end user readability in ambient lighting conditions. By using both luma (brightness) and chroma (color) contrast techniques on the display screen can be a background that stands out in the dark. For contrast enhancement, see Application Note 1015, Contrast Enhancement Technology LED Displays.

Note:

Test conditions specified in the Optical Properties table.