How Does The Expand 11 Click Board™ Work?
The Expand 11 Click Board™ is based on the TCA9536, a general-purpose I/O expander from Texas Instruments. It contains four 4-bit configuration ports alongside an I2C-compatible serial interface. Any four I/Os can be configured by the host MCU as an input or output by writing to the configuration register. During the Power-On sequence, the I/Os are configured as inputs with a weak pull-up to the selected mikroBUS™ power rail. The data for each input or output is kept in the corresponding register. The polarity of the Input Port register can be inverted with the Polarity Inversion register. The TCA9536 outputs (latched) have high-current drive capability for directly driving LEDs.
This Click board™ communicates with MCU using the standard I2C 2-Wire interface to read data and configure settings with a maximum frequency of 1MHz. The Expand 11 Click can also select the function of one of the ports, the P3 port, between its standard I/O and interrupt function. The selection is made by positioning SMD jumpers labelled P3 SEL in an appropriate position marked as I/O or INT. In addition to the jumper setting to the proper place, this function must also be set in the special function register to disable the internal pull-up resistors and P3 override to an INT output.
The Expand 11 Click Board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.
SPECIFICATIONS
| Type | Port expander |
| Applications | Can be used for system monitoring applications, industrial controllers, portable equipment, and more |
| On-board modules | TCA9536 - general-purpose I/O expander from Texas Instruments |
| Key Features | I2C to GPIO expander, wide supply range, 5V tolerant I/O ports, reset feature via serial interface, P3 port configurable as interrupt, polarity inversion, low power consumption, and more |
| Interface | I2C |
| Compatibility | mikroBUS |
| Click board size | M (42.9 x 25.4 mm) |
| Input Voltage | 3.3V or 5V |
PINOUT DIAGRAM
This table shows how the pinout of the Expand 11 Click Board™ 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 | INT | Interrupt | |
| NC | 3 | CS | RX | 14 | NC | ||
| NC | 4 | SCK | TX | 13 | NC | ||
| NC | 5 | MISO | SCL | 12 | SCL | I2C Clock | |
| NC | 6 | MOSI | SDA | 11 | SDA | I2C Data | |
| Power Supply | 3.3V | 7 | 3.3V | 5V | 10 | 5V | Power Supply |
| Ground | GND | 8 | GND | GND | 9 | GND | Ground |
ONBOARD SETTINGS AND INDICATORS
| Label | Name | Default | Description |
|---|---|---|---|
| LD1 | PWR | - | Power LED Indicator |
| JP1 | VCC SEL | Left | Logic Level Voltage Selection 3V3/5V: Left position 3V3, Right position 5V |
| JP2 | P3 SEL | Left | P3 Port Function Selection I/O/INT: Left position I/O, Right position INT |
EXPAND 11 CLICK ELECTRICAL SPECIFICATIONS
| Description | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage | 3.3 | - | 5 | V |