Turning Ideas Into Reality ABCircuits www.abcircuits.com POB 123 New Hill NC 27562 (919) 290-7104 SI14 IC Serial Input IC For 14 Bits of Input General Description The SI14 IC is designed to provide 14 bits of input data to connect to RS-232, RS-485, USB, Ethernet or directly to your UART. Inputs can be from switches, relay contacts, logic, optocouplers or a transistor switched to ground. The SI14 has internal pull resistors on the inputs to minimize additional parts. The SI14 IC transmits data anytime the inputs change or after a delay of 100 or 1000 mS. The output of the SI14 is standard asynchronous format, using 8 bits, 1 stop and no parity at 9600 BPS. Other formats and encoding are available, contact the factory. A .1 uF bypass capacitor is suggested across the VDD and VSS pins. The part uses the standard 20 pin .3 inch width SOIC package. This part may be paired with the SO14 chip to achieve 14 bits of input and output, except on RS-485 interfaces. Features • Asynchronous serial input for up to • • • • • • • • • • • • 14 bits of data. For input monitoring using RS-232, RS-485, USB or Ethernet or UART. Connects to switches, relay contacts, optocouplers, and logic. No external parts required. Low power consumption 5 mA typical. Applications • Input Expansion • Remote control • Process control • Building Automation • Off site monitoring • Security systems • Internet of things • Machine control Supply voltage 2.4 to 5.25 volts. All timing internally generated. On chip input pull up resistors on all inputs. TTL and CMOS compatible outputs. Part is in full production. SOIC and DIP 20 Pin Package. ROHS Compliant Low EMI Part Number 74C922-SO 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 Circuits 14 BITS INPUT ETHERNET B0 B2 B4 B6 A0 A2 A4 A6 +3.3 LANTRONIX XPORT +3.3 1 2 3 4 5 6 7 8 SI14 1 2 3 4 5 6 7 8 9 10 INPUT A5 INPUT A3 INPUT A1 INPUT B5 INPUT B3 INPUT B1 SPD IA5 IA3 IA1 NC SOUTIB5 IB3 IB1 VSS VDD IA6 IA4 IA2 IA0 NC IB6 IB4 IB2 IB0 20 19 18 17 16 15 14 13 12 11 GND +3.3 -POR OUT IN CP1 CP2 CP3 ETHERNET INPUT INPUT INPUT INPUT INPUT INPUT INPUT INPUT 14 BITS INPUT USB VCC INPUT B0 INPUT B2 INPUT B4 INPUT B6 INPUT A0 INPUT A2 INPUT A4 INPUT A6 .01 BEAD .1 .1 20 4 17 SPD IA5 IA3 IA1 NC SOUTIB5 IB3 IB1 VSS VDD IA6 IA4 IA2 IA0 NC IB6 IB4 IB2 IB0 20 19 18 17 16 15 14 13 12 11 16 15 CASE REFER TO FT232 DATASHEET FOR MORE DETAILS 19 27 28 8 24 USBM USBP -RST OSCI OSCO NC NC GND GND GND AGND TEST 1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 TXD RXD DTR -CTS RTS RI DSR DCD CBUS0 CBUS1 CBUS2 CBUS3 CBUS4 1 5 2 11 3 6 9 10 23 22 13 14 12 7 18 21 25 26 VCC INPUT B5 INPUT B3 INPUT B1 FT232-SSOP VCC VCCIO 3VOUT USB SI14 INPUT A5 INPUT A3 INPUT A1 4.7 Part Number SI14 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 14 BITS INPUT RS-232 VCC 16 B0 B2 B4 B6 A0 A2 A4 A6 C5 .1 1 3 C6 .1 4 5 VCC SI14 SPD IA5 IA3 IA1 NC SOUTIB5 IB3 IB1 VSS VDD IA6 IA4 IA2 IA0 NC IB6 IB4 IB2 IB0 20 19 18 17 16 15 14 13 12 11 10 12 9 V+ +5 C7 .1 2 C1C2+ V- 6 C8 .1 C2T1in T1out T2in T2out R1out R1in R2out R2in GND INPUT B5 INPUT B3 INPUT B1 1 2 3 4 5 6 7 8 9 10 U2 SEE NOTES RS232 DB9S J1 1 2 3 4 5 6 7 8 9 8 14 7 13 8 TXD GND 15 INPUT A5 INPUT A3 INPUT A1 11 C1+ VCC INPUT INPUT INPUT INPUT INPUT INPUT INPUT INPUT U2= MAX232 FOR 5V RS232 U2= MAX3232 FOR 3V RS232 14 BITS INPUT RS-485 INPUT INPUT INPUT INPUT INPUT INPUT INPUT INPUT B0 B2 B4 B6 A0 A2 A4 A6 VCC U2 1 VCC SI14 INPUT A5 INPUT A3 INPUT A1 INPUT B5 INPUT B3 INPUT B1 1 2 3 4 5 6 7 8 9 10 SPD IA5 IA3 IA1 NC SOUTIB5 IB3 IB1 VSS VCC 2 VDD IA6 IA4 IA2 IA0 NC IB6 IB4 IB2 IB0 20 19 18 17 16 15 14 13 12 11 3 4 RO VCC -RE -DO/-RI DE DO / RI DI GND 8 7 6 RS485 OUT 5 U2 75176 FOR 5V U2 MAX3485 FOR 3.3V Connection Diagram SI14 1 2 3 4 5 6 7 8 9 10 SPD IA5 IA3 IA1 NC SOUTIB5 IB3 IB1 VSS VDD IA6 IA4 IA2 IA0 NC IB6 IB4 IB2 IB0 20 19 18 17 16 15 14 13 12 11 Part Number SI14 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 Pin Description Pin # 1 2 3 4 5 6 7 8 9 10 Description SPD IA5 IA3 IA1 NC SOUTIB5 IB3 IB1 VSS Pin # 20 19 18 17 16 15 14 13 12 21 Description VDD IA6 IA4 IA2 IA0 NC IB6 IB4 IB2 IB0 IA0-6 and IB0-6 These are the input bits that will be transmitted when a change is detected, if no change is detected, they will be transmitted again after 100 mS or 1000 mS depending on the state of the SPD input. These inputs have internal pull up resistors. SPD This pin determines the delay before retransmit if the inputs do not change. If this pin is low or grounded, the delay is 1000 mS, if this pin is high or open, the delay is 100 mS. This input has an internal pull up resistor. SOUTThis is the serial output pin. It may be tied directly to the UART receiver input of your UART or microprocessor; to a RS -232 driver such as the MAX232; a standard RS485 driver such as the 75176 or an Ethernet interface such as the Lantronix Xport, or a USB IC such as the FT232. This pin is high in the idle state, the output format is 8 bits, 1 stop, no parity at 9600 BPS. Other output formats and baud rates are available, please contact the factory for information. When the bits of IA0-6 are transmitted, bit 8 of the transmitted byte is a zero. When the bits of IB0-6 are transmitted, bit 8 of the transmitted byte is a one. You can monitor this output with any hexadecimal terminal program like REALTERM. Hyperterm does not display in hexadecimal. 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 5 and 15 must be left unconnected. Serial Output Stream When the input bits on IA0-6 or IB0-6 change, or the delay times out, the SI14 transmits two bytes. The bits from IA0-6 are transmitted first, the eighth bit is a zero. When the bits of IB0-6 are transmitted, the eighth bit is a one. The SI14 automatically adds start and stop bits to the data stream. The data is transmitted at 9600 BPS, 8 bits, 1 stop, no parity. Part Number SI14 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 DATA STREAM START INPUT IA BITS IA0 IA1 IA2 IA3 IA4 INPUT IB BITS IA5 IA6 0 STOP START IB0 IB1 IB2 IB3 IB4 IB5 IB6 1 STOP BIT CELLS Absolute Maximum Ratings Symbol Description Tstg Ta V dd V io Imio ESD Storage Temperature Operating Temperature LU Latch up current V dd - V ss Voltage Input Voltage Maximum current into any pin Electrostatic Discharge Voltage Min -55 -40 -0.5 Typical Max Units 25 +100 +85 +6.0 ºC ºC V V mA V Vss - 0.5 -25 2000 V dd +0.5 +50 200 Notes Human Body Model ESD mA DC Electrical Characteristics Symbol Description V dd Idd V oh V ol V ih V il Ioh Iol Cio Iil Rpu Supply Voltage Supply Current High Output Level Low Output Voltage Input High Level Input Low Level High Level Source Current Low Level Sink Current Capacitive load Input leakage Pull Up Resistors On Inputs IA, IB, and SPD Min Typical Max Units 5 5.25 8 V mA V V V V mA mA pF nA k? 2.4 V dd - 1.0 0.75 2.1 4 3.5 1 5.6 0.8 10 25 10 8 Notes Note 1 Ioh=10 mA Iol=25 mA Note 1: Vdd=5VDC, all inputs and outputs open Theory Of Operation The SI14 IC is a custom programmed microprocessor designed to monitor inputs and provide a serial output. Anytime an input changes, the part transmits the data on the IA and IB pins. Bit 8 is low when IA is transmitted and high when IB is transmitted. The data is transmitted in standard asynchronous format on the SOUT key using 8 data bits, 1 stop bit and no parity. Baud rate is 9600 BPS. After the two bytes are transmitted, the inputs are monitored, and the SI14 will immediately transmit again if they change. If the data on IA0-6 and IB0-6 do not change, the part will retransmit the data again after a 100 or 1000mS delay, depending on the state of the SPD pin. Part Number SI14 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 – 20 Pin DIP (-DIP Suffix) Physical Dimensions – 20 Pin SOIC 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 SI14 Copyright © 2014 ABCircuits. Revised September 2014 Page 6 of 6