I2C-IN83M, I2C-IN83MA 8-Input Optocouplers I2C-bus, DIN rail supports Features PCF8574 and PCF8574A I2C chips upport khz I2C bus frequency On-board I2C bus pull-up resistors Address by 3 jumpers for use of up to 8 addresses Up to 6 boards on a bus Interrupt output signal On-board interrupt pull-up resistor Compatible with most microcontrollers 8 Optically isolated digital input channels 5-3VDC input voltage, I2C-IN83M, I2C-IN83MA 5-3VDC input voltage, I2C-IN83M, I2C-IN83MA 37VDC isolation input voltage Operating power supply voltage 3.3-5.5VDC Inverse polarity protection circuits DIN-rail supports PCB size 42.5x72.mm Description These are 8-channel opto-isolator boards for input expander over I2C bus. Each input of the I2C-IN83M and I2C-IN83MA accepts 5-3VDC. It is suitable for mechanical contact switching devices such as relay switches, push-buttons and switches. But each input of the I2C-IN83M and I2C-IN83MA accepts 5-3VDC. It is suitable for solid-state switching devices such as proximity switches. The boards use PCF8574 and PCF8574A for I2C chips. They support KHz bus speed and 3.3-5.5VDC bus voltage. Each board has three jumpers for setting an own I2C bus address. o they can be connected up to 6 boards on a bus by setting different addresses. Also there are I2C bus pull-up resistors and interrupt pull-up resistor on board which they can be enabled by jumpers. The board can be placed on DIN rail PCB holder which can be plugged on a DIN rail tray. Diagrams Inverse Polarity Protection IN IN2 CL DA I2C Controller PCF8574 PCF8574A 8 channels Opto-Isolator 8 8 Inverse Polarity Protection IN3 IN4 IN5 IN6 IN7 IN8 A A Figure : Block Diagram ERE Company Limited http://www.ereshop.com April 2, 24
I2C-IN83M, I2C-IN83MA, I2C-IN83M, I2C-IN83MA ADDREE R-PULL UP DA CL + IN - IN + IN2 - IN2 + IN3 - IN3 + IN4 - IN4 - IN8 + IN8 - IN7 + IN7 - IN6 + IN6 - IN5 + IN5 Figure 2: Board Diagram Table : Pin Descriptions ymbol CL DA R-PULL DA R-PULL CL R-PULL A A +IN +IN8 -IN -IN8 Descriptions Power supply input voltage 3.3-5.5VDC Ground I2C bus serial clock signal I2C bus serial data signal Interrupt output signal A jumper for selecting K pull-up resistor of DA signal A jumper for selecting K pull-up resistor of CL signal A jumper for selecting K pull-up resistor of signal A jumper for selecting address A A jumper for selecting address A A jumper for selecting address Positive voltage for input to input8 Negative voltage for input to input8 I2C Bus Pull-Up Registers The I2C bus wants pull-up resistors for CL and DA lines. The board has two of k pull-up resistors for this purpose. These resistors can be enabled by closing jumpers. These resistors have to be enabled if there is no any pull-up resistor on a bus or a microcontroller board. When multiple boards are connecting together on a bus. Usually the pull-up resistors of only one board are enabled. The bus is very strong if all pull-up resistors are enabled. o the microcontroller cannot drive the bus. ERE Company Limited. http://www.ereshop.com 2/7
I2C-IN83M, I2C-IN83MA, I2C-IN83M, I2C-IN83MA Enable Disable Disable Disable K K K K K K K K CL DA CL DA Board Board2 Board3 Figure 3: I2C bus pull-up resistors Board4 Interrupt ignal Interrupt output signal () on board can be connected to the interrupt input pin of microcontroller. The board sends an interrupt signal on this line. o the board can inform the microcontroller if there is incoming voltage on its inputs without having to poll over the I2C bus. The interrupt output pin is an open-drain and it is connected to K pull-up resistor via a jumper. When boards are connected together on an interrupt line. Usually the only one pull-up resister has to be enabled. Each board takes logical OR to another boards, many interrupt signals can occur at the same time. K K K K K x Enable Disable Disable Disable Disable Board Board2 Board3 Board4 Board5 Figure 4: Logical OR interrupt signals ERE Company Limited. http://www.ereshop.com 3/7
I2C-IN83M, I2C-IN83MA, I2C-IN83M, I2C-IN83MA DA CL DA CL to another board Figure 5: Interfacing The boards can be connected all together up to 6 boards on a bus by connecting 8 boards of I2C-IN83M and 8 boards of I2C-IN83MA. Because each board has own address which is difference to address of another boards. I2C-IN83MA (No. 6) Address 7F I2C-IN83MA (No. 5) Address 7D I2C-IN83MA (No. 4) Address 7B I2C-IN83MA (No. 9) Address 7 I2C bus I2C-IN83M (No. ) Address 4 I2C-IN83M (No. 6) Address 4B I2C-IN83M (No. 7) Address 4D I2C-IN83M (No. 8) Address 4F Figure 6: Boards on a bus ERE Company Limited. http://www.ereshop.com 4/7
I2C-IN83M, I2C-IN83MA, I2C-IN83M, I2C-IN83MA x4f A A A x7f A A A x4d A A A x7d A A A x4b A A A x7b A A A x49 A A A x79 A A A x47 A A A x77 A A A x45 A A A x75 A A A x43 A A A x73 A A A x4 A A A x7 A A A OPEN (HIGH) CLOE (LOW) I2C-IN83M PCF8574 OPEN (HIGH) CLOE (LOW) I2C-IN83MA PCF8574A Figure 7: Addressing Each board can be defined own address by setting jumper A, A and as above figure. ERE Company Limited. http://www.ereshop.com 5/7
IN 8 IN 7 IN 6 IN 5 I2C-IN83M, I2C-IN83MA, I2C-IN83M, I2C-IN83MA Input Diagram IN 4 IN 3 IN 2 I2C-IN83M PFC8574 IN When inputs are read through I2C protocol. The first byte is address and the second byte is data of inputs. IN will pass to P and IN2 will pass to P respectively, until IN8 will pass to P7. Table 2: Absolute maximum ratings at = 5VDC PAPAMETER I2C-IN83M, I2C-IN83MA I2C-IN83M, I2C-IN83MA Bus frequency Khz max Khz max I2C chips A A A P7 P6 P5 P4 P3 P2 P P A......... P I2C-IN83MA PFC8574A PCF8574 is used in I2C-IN83M PCF8574A is used in I2C-IN83MA Bus logic voltage 3.3-5.5 VDC 3.3-5.5VDC Max input voltage 3. VDC 3. VDC ON voltage/current ADDRE BYTE DATA BYTE DATA BYTE n A A A P7 P6 P5 P4 P3 P2 P P A......... P ADDRE BYTE DATA BYTE DATA BYTE n Figure 8: Input Data Frame 5. VDC min., 4mA 24. VDC, 7mA 3. VDC, 8.7mA PCF8574 is used in I2C-IN83M PCF8574A is used in I2C-IN83MA 5. VDC min, 3.5mA 2. VDC,.8mA 24. VDC, 22.8mA 3. VDC, 29mA OFF voltage/current 5. VDC max., ma 2. VDC max, ma Input impedance 3.3Kohm Kohm Max. boards on a bus 6 boards 6 boards Optical isolated input voltage 3.7kVDC 3.7kVDC Input channels 8 channels 8 channels Operating Temperature -7 C -7 C ERE Company Limited. http://www.ereshop.com 6/7
I2C-IN83M, I2C-IN83MA, I2C-IN83M, I2C-IN83MA Dimensions a A 2.mm I2C Bus Connector unit inch mm L 2.834 72. B W W C.673.2 42.5 28. D.629 6. E.57 4. B.358 34.5 E L C D C A a.279.4 7. 3.6 Figure 9: Dimensions ERE Company Limited. http://www.ereshop.com 7/7