Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 HEX7 IC BCD or Hexadecimal to Seven Segment Controller General Description The HEX7 IC is a two digit BCD or hexadecimal to seven segment convert er. Eight bits of parallel input is converted to drive two seven segment displays. Output polarity control is provided. The HEX7 IC has internal pull resistors on inputs to minimize additional parts. A .1 uF bypass capacitor is suggested across the VDD and VSS pins. The part uses the standard 28 pin .3 inch width SOIC and DIP packages. Features • Hexadecimal to seven segment • • • • • • • • • • • display converter. BCD to seven segment display converter. Applications • Numeric Displays . • Controls . • Price Signs . No external parts required. Low power consumption 5 mA typical. Supply voltage 2.4 to 5.25 volts. On chip input resistors. Output polarity select. TTL and CMOS compatible. Part is in full production. SOIC and DIP 28 Pin Package. ROHS Compliant. Low EMI. Part Number HEX7 Copyright © 2014 ABCircuits. Revised September 2014 Page 1 of 6 Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Example Circuit VCC 28 19 9 1 27 2 26 3 25 4 24 ( Parallel Input COMMON ANODE LEFT DISPLAY VCC HEX7 5 10 14 VDD NC NC SEGLG SEGLF SEGLE SEGLD SEGLC SEGLB SEGLA L8 L4 L2 L1 R8 R4 R2 R1 23 6 22 7 21 8 20 G F E D C B A A COM F B G E C D COMMON ANODE RIGHT DISPLAY VCC SEGRG SEGRF SEGRE SEGRD SEGRC SEGRB SERRA NC POL VSS 18 11 17 12 16 13 15 G F E D C B A A COM F B G E C D Connection Diagram HEX7 1 2 3 4 5 6 7 8 9 10 11 12 13 14 L8 L2 R8 R2 NC SEGLF SEGLD SEGLB NC POL SEGRF SEGRD SEGRB VSS VDD L4 L1 R4 R1 SEGLG SEGLE SEGLC SEGLA NC SEGRG SEGRE SEGRC SEGRA 28 27 26 25 24 23 22 21 20 19 18 17 16 15 Pin Description Pin # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Description L8 L2 R8 R2 NC SEGLF SEGLD SEGLB NC POL SEGRF SEGRD SEGRB VSS Pin # 28 27 26 25 24 23 22 21 20 19 18 17 16 15 Description VDD L4 L1 R4 R1 SEGLG SEGLE SEGLC SEGLA NC SEGRG SEGRE SEGRC SEGRA Part Number HEX7 Copyright © 2014 ABCircuits. Revised September 2014 Page 2 of 6 Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 POL Polarity input. If this pin is open or high, the “on” segments will have a high level on the SEG outputs of the chip. If this pin is low or grounded “on” segments will output as a low on the SEG pins. This pin is read once at power up and has a built in pull up resistor. SEGLA, SEGLB, SEGLC, SEGLD, SEGLE, SEGLF, SEGLG SEGRA, SEGRB, SEGRC, SEGRD, SEGRE, SEGRF, SEGRG SEGL is the left hand of the two displays. SEGR is the right hand of the two displays If the POL pin is open or hi, this SEG outputs will be high when a segment is on. If the POL pin is low or grounded, the SEG outputs will be low when a segment is on. These are the seven segment outputs to each individual display An external driver or current limiting resistor is required for each segment. If you are using only a resistor, it must be sized to limit source current to 5 mA maximum per pin or sink current to 9 mA per pin. See also the segment table, and the seven segment translation table. L1, L2, L4, L8 R1, R2, R4, R8 Parallel input of the data to be displayed. L1-4 is the left digit, R1-4 is the right digit. 1’s are least significant bit, and 8’s are most significant bit. VSS Connect to system ground. VDD Connect to supply voltage of 2.4 to 5 volts. A .1 uF decoupling capacitor to ground is recommended. NOTES: Make no connection to the NC pins. Pins 9 and 19 must be left unconnected. Segment Identification Table Part Number HEX7 Copyright © 2014 ABCircuits. Revised September 2014 Page 3 of 6 Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Seven Segment Translation Table Using Drivers For Brighter Displays VCC 10 9 COMMON ANODE LEFT DISPLAY VCC 28 19 9 ( Parallel Input 1 27 2 26 3 25 4 24 5 L8 L4 L2 L1 R8 R4 R2 R1 NC POL VSS SEGLG SEGLF SEGLE SEGLD SEGLC SEGLB SEGLA 23 6 22 7 21 8 20 1 2 3 4 5 6 7 8 IN1 IN2 IN3 IN4 IN5 IN6 IN7 IN8 OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 OUT8 18 17 16 15 14 13 12 11 G F E D C B A A COM F B G E C D ULN2804 COMMON ANODE RIGHT DISPLAY VCC ULN2804 SEGRG SEGRF SEGRE SEGRD SEGRC SEGRB SERRA 18 11 17 12 16 13 15 1 2 3 4 5 6 7 8 IN1 IN2 IN3 IN4 IN5 IN6 IN7 IN8 9 10 10 14 VDD NC NC COM GND HEX7 GND COM VCC OUT1 OUT2 OUT3 OUT4 OUT5 OUT6 OUT7 OUT8 18 17 16 15 14 13 12 11 G F E D C B A A COM F B G E C D VCC Absolute Maximum Ratings Symbol Description Tstg Storage Temperature -55 Ta V dd V io Operating Temperature Imio ESD Maximum current into any pin Electrostatic Discharge Voltage LU Latch up current V dd - V ss Voltage Input Voltage Min Typical Max Units 25 +100 ºC -40 -0.5 +85 +6.0 Vss - 0.5 -25 2000 V dd +0.5 +50 ºC V V 200 mA V Notes Human Body Model ESD mA Part Number HEX7 Copyright © 2014 ABCircuits. Revised September 2014 Page 4 of 6 Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 DC Electrical Characteristics Symbol Description V dd Idd V oh Supply Voltage Supply Current High Output Level V ol V ih V il Low Output Voltage Input High Level Input Low Level Ioh Iol Cio High Level Source Current Low Level Sink Current Capacitive load Iil Rpu Input leakage Pull Up Resistors On Inputs Min Typical Max Units 5 5.25 8 V mA V 0.75 Note 3 0.8 V V V mA mA pF Note 2 Note 3 3.5 10 25 10 1 5.6 8 nA k? 2.4 V dd - 1.0 2.1 4 Notes Note 1 Note 2 Note 1: Vdd=5VDC, all inputs and outputs open Note 2 Ioh=10 mA max per pin, 80 mA maximum all pins combined Note 3 Iol=25 mA max per pin 150 mA maximum all pins combined Theory Of Operation The HEX7 IC is a custom programmed microprocessor designed to monitor a parallel input and convert the received data to seven segment format. The device allows the outputs to be inverted if necessary to simplify driver construction. The IC displays in decimal (0-9) or hexadecimal (0-F) characters. Part Number HEX7 Copyright © 2014 ABCircuits. Revised September 2014 Page 5 of 6 Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Physical Dimensions SOIC-28 Physical Dimensions 28 Pin Dip Package (-DIP Suffix) Close but not quite? Our products are software based, we can modify existing parts to fit your needs at a minimal cost or create new parts designed to your specifications. Email us and we can make a chip for you! For the latest version of this spec sheet, visit www.abcircuits.com Design Services Available We can quickly turn your idea into a chip, a pc board, or a finished product. Contact us with your needs and specifications. Part Number HEX7 Copyright © 2014 ABCircuits. Revised September 2014 Page 6 of 6