SER7 ABCIRCUITS | Alldatasheet

Document overview

  • Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
  • PDF pages: 11

Technical content

Features

  • Drives one or two seven segment displays from serial data.
  • Converts from ASCII to seven segment codes .
  • Few external parts required.
  • Low power consumption 3 mA typical.
  • Supply voltage 2.4 to 5.25 volts.
  • All timing internally generated.
  • On chip input resistors.
  • Output polarity select .
  • Right or left hand decimal point displays.
  • Right or left display justificati on.
  • TTL and CMOS compatible.
  • Part is in full production.
  • SOIC and DIP 28 Pin Package.
  • ROHS Compliant .
  • Low EMI.

Applications

  • Data Displays
  • Vending Machines
  • Large display control
  • Numeric Displays
  • Controls
  • Ethernet displays
  • Price signs

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 2 of 11 Example Circuits – RS-232 display LEFT COMMON ANODE DISPLAY U2= MAX3232 FOR 3V RS232 RS232 VCC VCC U2= MAX232 FOR 5V RS232 GND TXD A B C D E F G DP G F E D C B A COM SER7 SEGRA NC SEGRC SEGRE SEGRG NC ADR2 SEGLF SEGLD SEGLB SEGRDP SEGRF SEGRB VSS SEGLE SEGRD SEGLA SEGLG VDD SEGLC ADR0 JUST DP SEGLDP SIN- ADR1 ADR3 POL RIGHT COMMON ANODE DISPLAY VCC DB9S RXD VCC SEE NOTES 1615 11 14 10 7 12 13 9 8 C1+ C1- C2+ C2- VCCGND T1in T1out T2in T2out R1out R1in R2out R2in A B C D E F G DP G F E D C B A COM VCC Example Circuits – RS-485 display VCC GND -DO/-RI DO / RI RO DI -RE DE VCC VCC A B C D E F G DP G F E D C B A COM VCC SER7 SEGRA NC SEGRC SEGRE SEGRG NC ADR2 SEGLF SEGLD SEGLB SEGRDP SEGRF SEGRB VSS SEGLE SEGRD SEGLA SEGLG VDD SEGLC ADR0 JUST DP SEGLDP SIN- ADR1 ADR3 POL A B C D E F G DP G F E D C B A COM LEFT COMMON ANODE DISPLAY U2 75176 FOR 5V VCC U2 MAX3485 FOR 3.3V RIGHT COMMON ANODE DISPLAY 4.7K VCC RS485 Example Circuits – USB display VCC VCC FT232-SSOP GND GND CBUS3 CBUS2 CBUS1 CBUS0 -CTS DTR RXD TXD -RST USBM USBP VCC VCCIO 3VOUT GND AGND NC NC TEST OSCI OSCO RTS RI DSR DCD CBUS4 SER7 SEGRA NC SEGRC SEGRE SEGRG NC ADR2 SEGLF SEGLD SEGLB SEGRDP SEGRF SEGRB VSS SEGLE SEGRD SEGLA SEGLG VDD SEGLC ADR0 JUST DP SEGLDP SIN- ADR1 ADR3 POL REFER TO FT232 DATASHEET FOR MORE DETAILS BEAD A B C D E F G DP G F E D C B A COM LEFT COMMON ANODE DISPLAY .01 RIGHT COMMON ANODE DISPLAY A B C D E F G DP G F E D C B A COM CASE VCC 4.7.1 USB VCC

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 3 of 11 Example Circuits – Ethernet display A B C D E F G DP G F E D C B A COM +3.3 A B C D E F G DP G F E D C B A COM SER7 SEGRA NC SEGRC SEGRE SEGRG NC ADR2 SEGLF SEGLD SEGLB SEGRDP SEGRF SEGRB VSS SEGLE SEGRD SEGLA SEGLG VDD SEGLC ADR0 JUST DP SEGLDP SIN- ADR1 ADR3 POL +3.3 +3.3 ETHERNET LANTRONIX XPORT GND +3.3 -POR OUT IN CP1 CP2 CP3 LEFT COMMON ANODE DISPLAY RIGHT COMMON ANODE DISPLAY +3.3 Connection Diagram SER7 5 24 SEGRA NC SEGRC SEGRE SEGRG NC ADR2 SEGLF SEGLD SEGLB SEGRDP SEGRF SEGRB VSS SEGLE SEGRD SEGLA SEGLG VDD SEGLC ADR0 JUST DP SEGLDP SIN- ADR1 ADR3 POL Pin Description Pin # Description Pin # Description

1 JUST 28 VDD

2 DP 27 POL

3 ADR2 26 ADR3

4 ADR0 25 ADR1

5 SEGLDP 24 SIN-

6 SEGLF 23 SEGLG

7 SEGLD 22 SEGLE

8 SEGLB 21 SEGLC

9 NC 20 SEGLA

10 SEGRDP 19 NC

11 SEGRF 18 SEGRG

12 SEGRD 17 SEGRE

13 SEGRB 16 SEGRC

14 VSS 15 SEGRA

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 4 of 11 POL Polarity input. If this pin is open or high, the “on” segments wil l 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. DP Right or left hand decimal input . This pi n should be open for right hand decimal displays or grounded for left hand decimal displays. This pin is read once at power up and has a built in pull up resistor. JUST Justification input. If this pin is open, the data received will be displayed right justified. If this pin is low or grounded, the data received will be displayed left justified. This pin is read once at power up and has a built in pull up resistor. See also the expansion examples. SIN- This is the serial input pin. It may be tied d irectly to the UART transmitter output of your UART or microprocessor; to a RS -232 receiver such as the MAX232 ; an Ethernet interface such as the Lantronix Xport; or a USB IC such as the FT232. This pin is hi gh in the idle state, the input format is 8 bit s, 1 stop, no parity at 9600 BPS. Other formats and baud rates are available, please contact the factory for information. This pin does not have an internal pull up resistor . It is recommended your software periodically send the data to the displays to recover from communications errors or power failures. You can drive this input with any terminal program like REALTERM or HYPERTERM for testing and development. ADR0-3 These pins determine the device address. Up to 16 devices can be used on the sam e communications channel, either on the same board, or on separate boards if a multi -drop interface such as RS -485 is used. See the example circuits for expansion details. Note that the JUST pin controls the placement of device address 0. If the pin i s low, (left justify) the Address 0 is on the left end of the chain, and the addresses increase going right. If this pin is open or high, (right justify) the address 0 is on the right side, and addresses increase going left.

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 5 of 11 Device Address ADR3 ADR2 ADR1A ADR0

0 Open Open Open Open

1 Open Open Open Ground

2 Open Open Ground Open

3 Open Open Ground Ground

4 Open Ground Open Open

5 Open Ground Open Ground

6 Open Ground Ground Open

7 Open Ground Ground Ground

8 Ground Open Open Open

9 Ground Open Open Ground

10 Ground Open Ground Open

11 Ground Open Ground Ground

12 Ground Ground Open Open

13 Ground Ground Open Ground

14 Ground Ground Ground Open

15 Ground Ground Ground Ground

SEGRA, SEGRB, SEGRC, SEGRD, SEGRE, SEGRF, SEGRG, SEGRDP SEGLA, SEGLB, SEGLC, SEGLD, SEGLE, SEGLF, SEGLG, SEGLDP SEGR is the right hand of the two displays. SEGL is the left 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 eight segmen t outputs to each individual display SEGDP is the decimal point . 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 ASCII to seven segment translation table. 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 .

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 6 of 11 Segment Identification Table

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 7 of 11 ASCII To Seven Segment Translation Table

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 8 of 11 Expansion Example, Left Justified ADDRESS 15ADDRESS 1 DISPLAY IN SER7 SEGR ADR2 SEGLADR0 JUST SIN- ADR1 ADR3 DISPLAY IN ADDRESS 0 DISPLAY IN SER7 SEGR ADR2 SEGLADR0 JUST SIN- ADR1 ADR3 DISPLAY IN DISPLAY IN SIN DISPLAY IN SER7 SEGR ADR2 SEGLADR0 JUST SIN- ADR1 ADR3 In left justify mode, address 0 is on the left . A one byte message will be displayed on the left digit of address 0. Expansion Example, Right Justified DISPLAY IN SER7 SEGR ADR2 SEGLADR0 JUST SIN- ADR1 ADR3 ADDRESS 1 DISPLAY IN SER7 SEGR ADR2 SEGLADR0 JUST SIN- ADR1 ADR3 DISPLAY IN ADDRESS 0ADDRESS 15 SIN DISPLAY IN SER7 SEGR ADR2 SEGLADR0 JUST SIN- ADR1 ADR3 DISPLAY IN DISPLAY IN In right justify mode, address 0 is on the right. A one byte message will be displayed on the right digit of address 0. Using Drivers For Brighter Displays VCC VCC SER7 SEGRA NC SEGRC SEGRE SEGRG NC ADR2 SEGLF SEGLD SEGLB SEGRDP SEGRF SEGRB VSS SEGLE SEGRD SEGLA SEGLG VDD SEGLC ADR0 JUST DP SEGLDP SIN- ADR1 ADR3 POL COMMON ANODE A B C D E F G RIGHT DISPLAY DP G F E D C B A COM A B C D E F G LEFT DISPLAY DP G F E D C B A COM COMMON ANODE VCCULN2804 17IN1 IN2 IN3 IN4 IN5 IN6 IN7 IN8 COMOUT8 OUT7 OUT6 OUT5 OUT4 OUT3 GND OUT1 OUT2 ULN2804 17IN1 IN2 IN3 IN4 IN5 IN6 IN7 IN8 COM OUT8 OUT7 OUT6 OUT5 OUT4 OUT3GND OUT1 OUT2 VCC SIN- VCC

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 9 of 11 Serial Input Stream When a byte is rec eived on the SIN - pin it is placed in the receive buffer. When a carriage return code (Hex 0D) is received on the SIN - pin, the data in the buf fer is translated and moved to the displays, Afterward the buffer is cleared. The SER7 uses the ADR0 -ADR3 pins to determine which bytes in the buffer to display. Notes: Receive buffer size is 32 bytes. Bit 8 (MSB of the data stream ) is ignored. Line feed characters (H ex 0A) are ignored. The decimal point (Hex 2E) activates the decimal point output. The decimal point is not d isplayed as a separate digit unless required. For instance “1.2” takes two digits to display. “12.” takes two digits to display in right hand decimal mode and three digits to display in left hand decimal mode. “.12” takes two digits to display in left hand decimal mode, and three digits to display in The data is format is 9600 BPS, 8 bits, 1 stop, no parity . Absolute Maximum Ratings Symbol Description Min Typical Max Units Notes Tstg Storage Temperature -55 25 +100 ºC Ta Operating Temperature -40 +85 ºC Vdd Vdd - Vss Voltage -0.5 +6.0 V Vio Input Voltage Vss - 0.5 Vdd +0.5 V Imio Maximum current into any pin -25 +50 mA ESD Electrostatic Discharge Voltage 2000 V Human Body Model ESD LU Latch up current 200 mA Symbol Description Min Typical Max Units Notes Vdd Supply Voltage 2.4 5.25 V Idd Supply Current 3 8 mA Note 1 Voh High Output Level Vdd - 1.0 V Note 2 Vol Low Output Voltage 0.75 V Note 3 Vih Input High Level 2.1 V Vil Input Low Level 0.8 V Ioh High Level Source Current 10 mA Note 2 Iol Low Level Sink Current 25 mA Note 3 Cio Capacitive load 3.5 10 pF Iil Input leakage 1 nA Rpu Pull Up Resistors On Inputs 4 5.6 8 k? Note 1: Vdd=5VDC, all inputs and outputs open Note 2 Ioh=10 mA max per pin, 80 mA maximum all p ins combined Note 3 Iol=25 mA max per pin 150 mA maximum all pins combined

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 10 of 11 Theory Of Operation The SER7 IC is a custom programmed microprocessor designed to monitor a serial input and convert the received data to seven segment format. When a byte is r eceived on the SIN - pin, bit 8 is c leared. The byte is then saved in the buffer. If the byte is a carriage return (0D hex) the IC uses the ADR0 -3 inputs to determine which two bytes in the buffer are converted to seven segment format and displayed. The data is standard asynchronous format 8 data bits, 1 stop bit and no parity. Baud rate is 9600 BPS. It is recommended that the display data be sent periodically even if there is no change, to recover from power failure or serial data errors.

Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 Part Number SER7 Copyright © 2014 ABCircuits. Revised September 2014 Page 11 of 11 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.