{"product_id":"8-mosfets-8-digital-inputs-for-raspberry-pi-io-back-panel","title":"8 MOSFETs and 8 Digital Inputs for Raspberry Pi I\/O Back Panel","description":"\u003cp\u003eThe \u003cstrong\u003e8 MOSFETs and 8 Digital Inputs Card\u003c\/strong\u003e features four high current outputs driving 8A and 48VDC loads and four high voltage outputs driving 4A and 200VDC loads. Each output is PWM controlled and has current measuring and current limiting capability. Each group of four MOSFETs is galvanically isolated. In addition, eight isolated inputs can read active high signals from 3V to 24VAC or DC.\u003c\/p\u003e\n\u003cp\u003eSeamlessly integrated with the Raspberry Pi Back Panel, the card supports Command Line,  MODBUS RTU over RS485, CAN support via CANopen, OpenPLC, and CODESYS.\u003c\/p\u003e\n\u003ch3\u003eFEATURES\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003ePlugs directly into the Raspberry Pi Back Panel - no additional wiring or hardware needed\u003c\/li\u003e\n\u003cli\u003eFour galvanically isolated 8A\/48VDC with 1KHz PWM MOSFET outputs\u003c\/li\u003e\n\u003cli\u003eFour galvanically isolated 4A\/200VDC with 1KHz PWM MOSFET outputs\u003c\/li\u003e\n\u003cli\u003eCurrent sensing on all outputs\u003c\/li\u003e\n\u003cli\u003eEight optically isolated 3-24VAC\/DC, PNP inputs\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eLED indicators on all inputs and outputs\u003c\/li\u003e\n\u003cli\u003eECCN classification: EAR99\u003c\/li\u003e\n\u003cli\u003eOpen source hardware - schematics available\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eDESCRIPTION\u003c\/h3\u003e\n\u003cp data-start=\"109\" data-end=\"538\"\u003ePart of the \u003cstrong\u003eHOP (Hardware On Panel)\u003c\/strong\u003e family developed by Sequent Microsystems, the \u003cstrong\u003e8 MOSFETs and 8 Digital Inputs Card \u003c\/strong\u003eplugs directly into the \u003ca rel=\"noopener\" title=\"Back Panel for Raspberry Pi Industrial Automation\" href=\"https:\/\/sequentmicrosystems.com\/products\/back-panel-for-raspberry-pi-industrial-automation\" target=\"_blank\"\u003eSequent Microsystems Back Panel\u003c\/a\u003e. \u003c\/p\u003e\n\u003cp data-start=\"109\" data-end=\"538\"\u003eUp to eight \u003cstrong\u003eHOP\u003c\/strong\u003e cards -of any type- can be installed on a single Back Panel, offering maximum flexibility for industrial automation applications. Multiple Back Panels can be connected horizontally to support larger projects.\u003c\/p\u003e\n\u003cp data-start=\"540\" data-end=\"643\"\u003eEight PNP inputs are wired to the Back Panel and can be accessed on the spring-loaded connectors. Inputs can read active high signals from 3V to 24VAC or DC. \u003c\/p\u003e\n\u003cp data-start=\"645\" data-end=\"1039\"\u003eLike all HOP cards, the 8-MOSFETs with PWM card features 18 LED indicators. The power LED blinks when power is applied and the local processor is operational. An error LED illuminates when the dedicated PANIC pin on the Back Panel terminal block is activated. Eight LEDs display the real-time status of each input. Eight more LEDs show the status of the outputs.\u003c\/p\u003e\n\u003cp data-start=\"1041\" data-end=\"1170\"\u003eAn RS485 port enables communication with external PLCs or industrial controllers using the industry-standard \u003cstrong\u003eMODBUS RTU\u003c\/strong\u003e protocol.\u003c\/p\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003cp data-start=\"139\" data-end=\"161\"\u003e\u003cstrong\u003ePower Requirements\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"163\" data-end=\"220\"\u003eThe \u003cstrong\u003e8 MOSFETs and 8 Digital Inputs Card\u003c\/strong\u003e is powered via the Back Panel power connector.\u003c\/p\u003e\n\u003cul data-start=\"221\" data-end=\"422\"\u003e\n\u003cli data-start=\"221\" data-end=\"315\"\u003e\n\u003cp data-start=\"223\" data-end=\"315\"\u003eMOSFET outputs are open drain and the load has to be powered from an external power supply. Connection to the system ground is optional, depending on your application.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"316\" data-end=\"422\"\u003e\n\u003cp data-start=\"318\" data-end=\"422\"\u003eThe \u003cstrong data-start=\"322\" data-end=\"341\"\u003elocal processor\u003c\/strong\u003e is powered from the 5V rail through a 3.3V LDO regulator and consumes \u003cstrong data-start=\"412\" data-end=\"421\"\u003e10 mA\u003c\/strong\u003e.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cp data-start=\"104\" data-end=\"124\"\u003e\u003cstrong\u003eError Processing\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"126\" data-end=\"439\"\u003eOne pin on the spring-loaded terminal block of the Back Panel is reserved for signaling an error condition. The user can connect this pin to an external contact of their choice. When the error signal is activated, the 8-MOSFETs with PWM card automatically resets all outputs to a predefined default state.\u003c\/p\u003e\n\u003cp data-start=\"126\" data-end=\"439\"\u003e\u003cstrong\u003eCurrent Sensing Outputs\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"126\" data-end=\"439\"\u003eEach open-drain output is routed to the output through a Hall Effect-Based Linear Current Sensor IC.. The sensor has a maximum scale of 10A, a bandwidth of 150KHz and 2.6 kVRMS Isolation. This allows the system to calculate the power consumed by each load, limit the current, or disable the output if a predefined current threshold is exceeded.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"text-align: start;\"\u003e\n\u003cstrong\u003eWATCHDOG:\u003c\/strong\u003e If the watchdog is enabled and the Raspberry Pi fails to access the 8-MOSFETs with PWM Card within the preset time, the card signals the Back Panel, which performs a hard reset of the Raspberry Pi by turning the power off for 10 seconds.\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eSTACK LEVEL: \u003c\/strong\u003eThe stack level is automatically determined by the slot into which the card is inserted on the Back Panel. It is shown on the OLED display after power up. Up to eight cards of the same type can be connected to a single Back Panel installation.\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cstrong\u003eINTERRUPT:\u003c\/strong\u003e Any HOP card can be programmed to interrupt the Raspberry Pi. The interrupt handler running on Raspberry Pi needs to monitor pin 37 on the GPIO interface.\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\u003cstrong\u003eBACK PANEL TERMINAL BLOCK PINOUT\u003c\/strong\u003e\u003c\/div\u003e\n\u003cdiv\u003eEach slot on the Back Panel has alocated three 6-pin spring-loaded terminal blocks for IO wiring. The pinout is shown in the following picture:\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: start;\"\u003e\u003cimg alt=\"Raspberry Pi Backpanel Terminal Block IO\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0534\/4392\/0067\/files\/TerminalBlock-IO_480x480.jpg?v=1759503531\" style=\"margin-bottom: 16px; float: none;\"\u003e\u003c\/div\u003e\n\u003cdiv\u003eThe \u003cstrong\u003e8 MOSFETs and 8 Digital Inputs Card \u003c\/strong\u003ehas the input lines routed to the Back Panel as follows: Odd-numbered inputs are routed to the positive side, and even-numbered inputs to the negative side. AC signals can be routed either way.\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv\u003eIO01-IO02: Input #1\u003c\/div\u003e\n\u003cdiv\u003eIO03-IO04: Input #2\u003c\/div\u003e\n\u003cdiv\u003eIO05-IO06: Input #3\u003c\/div\u003e\n\u003cdiv\u003eIO07-IO08: Input #4\u003c\/div\u003e\n\u003cdiv\u003eIO09-IO10: Input #5\u003c\/div\u003e\n\u003cdiv\u003eIO11-IO12: Input #6\u003c\/div\u003e\n\u003cdiv\u003eIO13-IO14: Input #7\u003c\/div\u003e\n\u003cdiv\u003eIO15-IO16: Input #8\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cdiv\u003eIO17: ERROR\u003c\/div\u003e\n\u003cdiv\u003eIO18: PANIC\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv\u003eIO17 is an open drain output triggered by a predefined error condition on an out of bounds input. It can be used to activate an external alarm, or can be routed back to IO18 to reset the outputs to a predefined state.\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv\u003eIO18 is a dry contact to ground input and can be activated by an external contact wired to the Back Panel terminal block. When triggered, it resets all outputs to a predefined state. \u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"text-align: start;\"\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003cstrong\u003eDOT MATRIX DISPLAY\u003c\/strong\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: start;\"\u003e\u003cimg alt=\"OLED for 8-MOSFETS HOP\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0534\/4392\/0067\/files\/8xMOSFETS-8xIN-OLED_480x480.jpg?v=1759016767\" style=\"margin-bottom: 16px; float: none;\"\u003e\u003c\/div\u003e\n\u003cdiv style=\"text-align: start;\"\u003eThe \u003cstrong\u003e8 MOSFETs and 8 Digital Inputs Card\u003c\/strong\u003e includes a 128 × 32 dot-matrix display driven by the on-board processor. It can show status information, self-test results, and error messages. At power up it displays the card name, the I2C address, the slot position and the value of the 24V supply.\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003cdiv\u003e\n\u003c!--block--\u003e\u003cstrong\u003eELECTRICAL SPECIFICATIONS\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003c!--block--\u003ePower Supply Back Panel provided:\u003c\/li\u003e\n\u003cli\u003e5V 10mA\u003c\/li\u003e\n\u003cli\u003e24V 10mA\u003cbr\u003e\n\u003c\/li\u003e\n\u003cli\u003eLoad power user provided\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv\u003e\n\u003c!--block--\u003e\u003cstrong\u003eMECHANICAL SPECIFICATIONS\u003c\/strong\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"text-align: start;\"\u003e\n\u003c!--block--\u003e\u003cspan data-trix-cursor-target=\"true\" data-trix-serialize=\"false\"\u003e\u003c\/span\u003e\n\u003cfigure class=\"attachment attachment-preview\" data-trix-attachment='{\"contentType\":\"image\",\"height\":387,\"url\":\"https:\/\/cdn.shopify.com\/s\/files\/1\/0534\/4392\/0067\/files\/ModularIndustrial-Mech.jpg?v=1633452393\",\"width\":600}' data-trix-content-type=\"image\" data-trix-id=\"722\"\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0534\/4392\/0067\/files\/mechanical_480x480.jpg?v=1751297156\" alt=\"8-MOSFETS with PWM card mechanical\" style=\"margin-bottom: 16px; float: none;\"\u003e\u003cbr\u003e\n\u003cfigcaption class=\"caption\"\u003e\u003c\/figcaption\u003e\n\u003c\/figure\u003e\n\u003cspan data-trix-cursor-target=\"true\" data-trix-serialize=\"false\"\u003e\u003c\/span\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n\u003c!--block--\u003e\u003cstrong\u003e \u003c\/strong\u003e\n\u003c\/div\u003e\n\u003ch3\u003e\n\u003c!--block--\u003eDOWNLOADS\u003c\/h3\u003e\n\u003cp\u003e\u003ca rel=\"noopener\" title=\"Eight MOSFETS with PWM for Raspberry Pi Back Panel - Schematic V1.0\" href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0534\/4392\/0067\/files\/8xMOSFETS-8-IN-Schematic-V1_0.pdf?v=1752714510\" target=\"_blank\"\u003eHardware Schematic V1.0\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca rel=\"noopener\" title=\"Back Panel for Raspberry Pi IO Plugin Card mechanical Specs\" href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0534\/4392\/0067\/files\/mechanical.dxf?v=1751297638\" target=\"_blank\"\u003e2D DXF Mechanical\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e\u003ca rel=\"noopener\" title=\"Eight MOSFETS with PWM 3D STEP Model\" href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0534\/4392\/0067\/files\/8xMOSFETS-8-IN-STEP-V1_0.zip?v=1752714858\" target=\"_blank\"\u003e3D STEP Model\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e3D Printable Enclosure\u003c\/p\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003ch3\u003e\n\u003c!--block--\u003eSOFTWARE\u003c\/h3\u003e\n\u003cdiv\u003e\n\u003cp\u003eCommand Line Drivers\u003c\/p\u003e\n\u003cp\u003ePython Libraries\u003c\/p\u003e\n\u003cp\u003eCODESYS Driver\u003c\/p\u003e\n\u003cp\u003eOpenPLC Module\u003c\/p\u003e\n\u003cbr\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\u003c!--block--\u003e\u003c\/div\u003e\n\u003cdiv\u003e\u003c!--block--\u003e\u003c\/div\u003e\n\u003ch3\u003e\n\u003c!--block--\u003eQUICK START\u003c\/h3\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003c!--block--\u003ePlug the \u003cstrong\u003e8 MOSFETs and 8 Digital Inputs Card \u003c\/strong\u003eon the Back Panel for Raspberry Pi and power up the system.\u003c\/li\u003e\n\u003cli\u003e\n\u003c!--block--\u003eEnable I2C communication on Raspberry Pi using raspi-config.\u003c\/li\u003e\n\u003cli\u003e\n\u003c!--block--\u003eInstall the software from github.com:\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cul\u003e\n\u003cli\u003egit clone https:\/\/github.com\/SequentMicrosystems\/sequent-cli.git\u003c\/li\u003e\n\u003cli\u003ecd \/home\/pi\/sequent-cli\u003c\/li\u003e\n\u003cli\u003esudo make install\u003c\/li\u003e\n\u003cli\u003e\n\u003c!--block--\u003esequent-cli 8mos-8in -h\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cdiv\u003e\n\u003c!--block--\u003eThe program will respond with a list of available commands.\u003c\/div\u003e\n\u003cdiv\u003e\u003cbr\u003e\u003c\/div\u003e\n\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cp data-start=\"300\" data-end=\"628\"\u003e\u003cstrong data-start=\"300\" data-end=\"349\"\u003eQ: What is the primary function of this card?\u003c\/strong\u003e\u003cbr data-start=\"349\" data-end=\"352\"\u003eA: It provides 8-MOSFET output channels (four high-current, four high-voltage) with PWM control and real-time current sensing. It's designed for switching and monitoring DC loads in automation, lighting, and motor control systems using the Sequent Microsystems Back Panel.\u003c\/p\u003e\n\u003cp data-start=\"630\" data-end=\"948\"\u003e\u003cstrong data-start=\"630\" data-end=\"686\"\u003eQ: What types of loads can I control with this card?\u003c\/strong\u003e\u003cbr data-start=\"686\" data-end=\"689\"\u003eA: The card is designed to drive \u003cstrong data-start=\"722\" data-end=\"739\"\u003eDC loads only\u003c\/strong\u003e, such as motors, solenoids, LEDs, and heating elements. High-current outputs support up to 8A @ 24 V DC, while high-voltage outputs handle up to 4 A @ 200V DC. \u003cstrong data-start=\"902\" data-end=\"948\"\u003eIt is not suitable for switching AC loads.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"950\" data-end=\"1164\"\u003e\u003cstrong data-start=\"950\" data-end=\"994\"\u003eQ: How is the stack position determined?\u003c\/strong\u003e\u003cbr data-start=\"994\" data-end=\"997\"\u003eA: Stack position is \u003cstrong data-start=\"1018\" data-end=\"1044\"\u003eautomatically assigned\u003c\/strong\u003e based on the physical slot the card occupies on the Back Panel. No DIP switches or software configuration are required.\u003c\/p\u003e\n\u003cp data-start=\"1166\" data-end=\"1457\"\u003e\u003cstrong data-start=\"1166\" data-end=\"1206\"\u003eQ: How is the RS485 port configured?\u003c\/strong\u003e\u003cbr data-start=\"1206\" data-end=\"1209\"\u003eA: The RS485 port is \u003cstrong data-start=\"1230\" data-end=\"1255\"\u003epermanently connected\u003c\/strong\u003e to the shared RS485 bus on the Back Panel. It is managed by the onboard processor and supports MODBUS RTU slave communication. The Raspberry Pi does not directly control the RS485 signals on this card.\u003c\/p\u003e\n\u003cp data-start=\"1459\" data-end=\"1796\"\u003e\u003cstrong data-start=\"1459\" data-end=\"1501\"\u003eQ: How is current sensing implemented?\u003c\/strong\u003e\u003cbr data-start=\"1501\" data-end=\"1504\"\u003eA: Each output is routed through a Fully Integrated, Hall Effect-Based Linear Current Sensor IC with 150kHz Bandwidth and 2.6 kVRMS Isolation with a maximum scale of 10A. The sensor provides a 0-3.3V output proportional with the load current. The output is measured with 12 bit A\/D converters. This allows the system to monitor load current, calculate power, and enforce current limits by shutting off outputs when thresholds are exceeded.\u003c\/p\u003e\n\u003cp data-start=\"1798\" data-end=\"1987\"\u003e\u003cstrong data-start=\"1798\" data-end=\"1834\"\u003eQ: Can I use PWM on all outputs?\u003c\/strong\u003e\u003cbr data-start=\"1834\" data-end=\"1837\"\u003eA: Yes, all eight outputs support software-controlled PWM at 1 kHz, enabling fine-grained control of load power such as motor speed or LED brightness.\u003c\/p\u003e\n\u003cp data-start=\"1989\" data-end=\"2216\"\u003e\u003cstrong data-start=\"1989\" data-end=\"2040\"\u003eQ: Can the card operate without a Raspberry Pi?\u003c\/strong\u003e\u003cbr data-start=\"2040\" data-end=\"2043\"\u003eA: Yes. When connected via RS485, the onboard processor allows the card to function as a MODBUS RTU slave, making it controllable by any MODBUS-compatible PLC or controller.\u003c\/p\u003e\n\u003cp data-start=\"2218\" data-end=\"2430\"\u003e\u003cstrong data-start=\"2218\" data-end=\"2292\"\u003eQ: Is the card software-compatible with other Sequent MOSFET products?\u003c\/strong\u003e\u003cbr data-start=\"2292\" data-end=\"2295\"\u003eA: Yes. It uses the same command-line tools and open-source libraries as other Sequent Microsystems cards, including Python and C APIs.\u003c\/p\u003e\n\u003cp data-start=\"2432\" data-end=\"2602\"\u003e\u003cstrong data-start=\"2432\" data-end=\"2463\"\u003eQ: How is the card powered?\u003c\/strong\u003e\u003cbr data-start=\"2463\" data-end=\"2466\"\u003eA: The card accepts 5 V and 24 V DC through the Back Panel. The 24V supply is used to generate isolated 12V supplies for the MOSFET gate drivers. An onboard regulator generates 3.3V for the local processor.\u003c\/p\u003e\n\u003cp data-start=\"2604\" data-end=\"2803\"\u003e\u003cstrong data-start=\"2604\" data-end=\"2660\"\u003eQ: What happens if a load exceeds the current limit?\u003c\/strong\u003e\u003cbr data-start=\"2660\" data-end=\"2663\"\u003eA: The card can automatically disable the affected output when current exceeds a user-defined threshold, protecting the load and the system.\u003c\/p\u003e\n\u003cp data-start=\"3173\" data-end=\"3424\"\u003e\u003cstrong data-start=\"3173\" data-end=\"3224\"\u003eQ: Where can I find documentation and examples?\u003c\/strong\u003e\u003cbr data-start=\"3224\" data-end=\"3227\"\u003eA: Visit Sequent Microsystems’ GitHub repository for open-source code, wiring diagrams, and setup instructions:\u003cbr data-start=\"3338\" data-end=\"3341\"\u003e👉 \u003ca data-start=\"3344\" data-end=\"3424\" class=\"\" rel=\"noopener\" href=\"https:\/\/github.com\/SequentMicrosystems\"\u003ehttps:\/\/github.com\/SequentMicrosystems\u003c\/a\u003e\u003c\/p\u003e\n\u003cdiv\u003e\u003c!--block--\u003e\u003c\/div\u003e","brand":"Sequent Microsystems","offers":[{"title":"Default Title","offer_id":47323850178812,"sku":"SM-P-770","price":145.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0534\/4392\/0067\/files\/8-mos6_a7156b73-18e7-4444-bf77-18b444730f1e.jpg?v=1774193600","url":"https:\/\/sequentmicrosystems.com\/products\/8-mosfets-8-digital-inputs-for-raspberry-pi-io-back-panel","provider":"Sequent Microsystems","version":"1.0","type":"link"}