Expand 8 Click Board™

Product Code: MIKROE-4442

How Does the Expand 8 Click Board™ work? The Expand 8 Click Board™ as its foundation uses the MAX7317, a general-purpose input/output (GPIO) peripheral from Maxim Integrated that provides 10 I/O ports, P0 to P9, controlled through a high-speed SPI-compatible serial interface. Each port, P0 to P9 can be configured as open-drain, current-sink outputs rated at 20mA maximum, or as CMOS inputs, or as open-drain outputs. Loads should be connected to a supply voltage no higher than 7V. The MAX7317 contains ten 8-bit internal registers. These ten registers are addressed as 0x00 - 0x09 control an I/O port each. Write 0x00 to the output register to set the port as a logic-low output, or 0x01 to set the port as a logic-high output or logic input. Expand 8 Click communicates with MCU through a 16-bit 4-wire serial interface compatible with standard SPI, QSPI™, MICROWIRE™ guaranteed to operate at 35Mbps on its 3.3V power supply. During the Power-Up sequence, all control registers of the MAX7317 are in a reset state.

Power-Up status sets I/O ports, P0 to P9, into a high impedance state and puts the device into Shutdown mode. The I/O ports P0–P9 remains high impedance with up to 8V asserted on them when the MAX7317 is powered down. Therefore, it can be used in hot-swap applications. This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before use with MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used, as a reference, for further development. SPECIFICATIONS Type Port expander Applications Intended for use as a port expander in system monitoring applications, industrial controllers, portable equipment, and many more. On-board modules MAX7317 - 10-Port SPI-interfaced I/O expander with overvoltage and hot-insertion protection from Maxim Integrated Key Features 10-Port I/O expander, overvoltage protection, support hot-insertion, SPI, QSPI™, MICROWIRE™ compatible serial interface, low power consumption, and more. Interface SPI Compatibility mikroBUS Click board size M (42.9 x 25.4 mm) Input Voltage 3.3V PINOUT DIAGRAM This table shows how the pinout on Expand 8 Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns). Notes Pin Pin Notes NC 1 AN PWM 16 NC NC 2 RST INT 15 NC SPI Chip Select CS 3 CS RX 14 NC SPI Clock SCK 4 SCK TX 13 NC SPI Data OUT SDO 5 MISO SCL 12 NC SPI Data IN SDI 6 MOSI SDA 11 NC Power Supply 3.3V 7 3.3V 5V 10 NC Ground GND 8 GND GND 9 GND Ground ONBOARD SETTINGS AND INDICATORS Label Name Default Description LD1 PWR - Power LED Indicator J1-J2 P0-P9 Populated I/O Expander Port EXPAND 8 CLICK ELECTRICAL SPECIFICATIONS Description Min Typ Max Unit Supply Voltage - 3.3 - V Output Load Voltage P0 - P9 - - 7 V Maximum Output Current - - 20 mA Operating Temperature Range -40 +25 +125 °C