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The RoHS icon on this product indicates that the PCBs, components, solder, and chemicals are all lead-free and RoHS compliant. Additionally, this product is produced using a lead-free process. Unfortunately, we are currently unable to provide documentation confirming that this product is RoHS compliant.
Resources:
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Package Includes:
Notes:
- This board uses 4-pin connectors for I2C bus.
Features:
- PCF8574A I2C bus chips
- 100kHz I2C bus frequency
- Selectable I2C bus pulling-up resistors
- Addressable via 3 jumpers for up to 8 addresses
- Supports up to 16 boards on a single bus
- Compatible with most microcontrollers
- Supports Microcontroller ports with 2.5 to 5.5V operating voltage
- 8 relay outputs
- 5Vdc coil voltages
- Relay contact rating: 0.5A @120Vac, 1A @30Vdc, 0.15A @48Vdc
- I2C operating voltage ranges: 2.5Vdc to 5.5Vdc
- On-board reverse polarity protection circuits
- Small PCB size: 81.6 x 36.1 mm
This is an I2C relay board, designed as a remote relay board for the I2C bus. It is perfect for use as a relay output expander, especially in applications with limited space. The board is based on the PCF8574A I/O expander, and both PCF8574 and PCF8574A boards can be connected to a single bus, supporting up to 8 boards, or a total of 16 boards when using both PCF8574 and PCF8574A on the same bus.
I2C Bus Frequency: The board supports a 100kHz bus frequency, ensuring reliable communication.
Selectable Pull-Up Resistors: It features selectable pull-up resistors for the SDA and SCL signals, making it adaptable to different bus configurations.
Relay Configuration: The board contains 8 small relays, and users can select whether the relay coil input voltage is powered by the bus voltage or an external source.
Protection Circuitry: Built-in inverse polarity protection circuits help prevent damage from incorrect power supply connections.
Connection Simplified: The board includes double 4-pin bus connectors, making it easier to connect multiple boards than previous versions.
LED Indicator: An LED indicator is provided, lighting up to show when input voltage is properly applied to the board.
Mounting Compatibility: The board's mounting holes are compatible with older versions like the EI2C-9AI and EI2C-9AIA, simplifying upgrades or replacements.
Important Safety Notice:
To prevent damage to the board, never plug or unplug I2C cables while the power supply is turned on. Always ensure the power supply is turned off before connecting or disconnecting I2C cables.
