The MAX7316 is an I2C/SMBus-compatible serial interfaced peripheral that provides microprocessors with eight additional I/O ports plus one output-only port and one input-only port. Each I/O port can be individually configured as an open-drain current-sinking output rated to 50mA at 5.5V or as a logic input with transition detection. The output-only port can also be assigned as an interrupt output for transition detection. The outputs are capable of driving LEDs or providing logic outputs with external resistive pullup up to 5.5V. Eight-bit PWM current control is available for all nine output ports. Four bits are global control and apply to all LED outputs to provide coarse adjustment of current from fully off to fully on in 14 intensity steps. Additionally, each output has individual 4-bit control, which further divides the globally set current into 16 more steps. Alternatively, the current control can be configured as a single 8-bit control that sets all outputs at once. Each output has independent blink timing with two blink phases. LEDs can be individually set to be on or off during either blink phase or to ignore the blink control. The blink period is controlled by an external clock input (up to 1kHz) on BLINK or by a register. The BLINK input can also be used as a logic control to turn the LEDs on and off or as a general-purpose input. The MAX7316 supports hot insertion. All port pins, the INT output, SDA, SCL, RST, BLINK, and the slave a
The MAX7316 is a general‑purpose I/O expander that provides eight configurable I/O ports plus a ninth output‑only port. It communicates over a 2‑wire I²C/SMBus interface and supports hot‑insertion, open‑drain outputs rated for 50 mA, and programmable LED PWM intensity control.
Key features include four selectable I²C slave addresses, 8‑bit PWM current control with both global and per‑port resolution, 2‑phase LED blinking, low standby current, and operation over a temperature range of –40 °C to +125 °C.
| Operating Supply Voltage (V+) | 2.0 V – 3.6 V |
|---|---|
| Maximum Output Current per Port | 50 mA (5.5 V) |
| PWM Clock Frequency | 32 kHz (nominal) |
| Operating Temperature Range | -40 °C to +125 °C |
The device can be set to one of four I²C addresses using the AD0 pin.
Each open‑drain I/O port can sink up to 50 mA at 5.5 V.
It uses an internal oscillator nominally at 32 kHz to generate PWM timing.