Features

• Inexpensive Decoder Solution
• Code 39 (or code 3 of 9) or UPC-A
• No External Memory Required
• Serial Interface
• Minimal External Components
• Read and Transmit complete barcode
• Interface with any electronic circuit, PCB, embedded project, etc.

Description

The Barcode Decoder IC Chip Series decoder chips are offered as an inexpensive decoding solution where a numeric, fixed length barcode can be used. The decoder decodes Code39 or UPC-A barcode in fixed lengths of 1 to 14 digits (for code 39) or 1 to 12 digits (for UPC-A). A professionally designed programming algorithm has been used on the barcode decoder chip to reduce the risk of false reads. Among its competitors the NEX (NewElectronX) Barcode Decoder IC Chip has the advantage of being easy to use and interface with any embedded microprocessor or system to produce a barcode symbol read out of Code39 and UPC-A symbologies. Using the NEX Barcode Decoder IC Chip, a minimal number of additional components is necessary to construct a decoder that will read and transmit barcode data via an serial interface or equivalent.

Application

The NEX Barcode Decoder IC Chips Series is designed to be incorporated into the user’s printed circuit board, embedded projects, keyboards, logic system, inventory systems, and more. The decoder chips are available in either surface mount (SMT / SOIC) or DIP 28-pin packages. No external memory or latch chips are required, keeping component count to a minimum. External circuitry includes ONLY a crystal (or saw resonator), 1 resistor, and optical scanning wand. The decoder can be interfaced with a reset/watchdog chip such as a MAX824 and/or an RS-232 communications chip like the MAX232 or equivalent. Extra bells and whistles can also be used with the barcode decoder chip like a speaker for audible sound indications and an LED for visual indications. A general application circuit is shown below. Good circuit layout practices are required when designing a circuit board.

General Specification

Absolute Maximum Ratings

Pin Description Pin # Pin Name Type Function 1 RESET I External system reset pin. Active LOW digit input. Bring this pin LOW to reset the Decoder. Recommended use is after the host embedded controller power-up or a wand scan error. Connect to an IC, switch, etc. to control reset feature. 2 DB4 O DB4…DB7 are grouped together for LCD pin connection. If used. 3 DB5 O 4 DB6 O 5 DB7 O 6 RS SEL O Control/Display LCD select pin. 7 ENABLE O The clock pin on the LCD. 8, 19 GND, GROUND G Decoder system ground. Connect to power supply’s ground (GND) terminal. 9 OSC1 I/O Decoder system  clock, connect to 20MHz resonator. Connect middle pin of resonator to ground. 10 OSC2 I/O 15 SPEAKER/BUZZER O Active HIGH output to differential positive speaker driver output. Designed to drive a 32 Ω speaker. An buzzer can also be used. Will sound on initial power up of the decoder chip. Will also sound twice for bad wand scan and once for good wand scan. 16 LED O Active HIGH output. LED will light for 1 second at start up to indicate decoder chip power is ON and then turn OFF. The LED will also light when a wand scan is in progress and turn OFF when the scan is complete.   17 TX SOUT O Serial Out. TTL-Level interface can be any baud 1200 to 1250000. Default baud is 115200 unless advised otherwise at purchase: Inverted, No parity, 8 data bits, 1 Stop bit, Baud 115200(default) 20 VDD P System power. 4.2V to 5.5V, unless lower power ratings have been ordered. 25 BARCODE VIDEO INPUT I This TTL Level signal pin reads (bar = +) the output from any Hewlett Packard Bar Code wands or equivalent optical scanners or barcode readers wands.

Application Circuit   Dimensional Drawing