The MAX7315 is an I2C/SMBus-compatible serial interfaced peripheral that provides microprocessors with 8 I/O ports. Each I/O port can be individually configured as either an open-drain current-sinking output rated at 50mA at 5.5V, or a logic input with transition detection. A ninth port can be used for transition detection interrupt or as a general-purpose output. The outputs are capable of directly driving LEDs, or providing logic outputs with external resistive pullup up to 5.5V. PWM current drive is integrated with 8 bits of control. 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. Each output then 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. The MAX7315 is pin and software compatible with the PCA9534 and PCA9554(A). Each output has independent blink timing with two blink phases. All 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 a register. The MAX7315 is controlled through the 2-wire I2C/SMBus serial interface, and can be configured to one of 64 I2C addresses.
The MAX7315 is a general‑purpose I/O expander that provides eight configurable ports plus a ninth port usable as an interrupt or general‑purpose output. Each port can operate as an open‑drain output (up to 50 mA at 5.5 V) or as a logic input with transition detection. Integrated PWM and LED‑intensity control allow fine brightness adjustment for LED applications.
The device communicates over a 2‑wire I²C/SMBus interface, supports 400 kHz clock rates, and can be addressed to any of 64 possible slave addresses. It operates from 2 V to 3.6 V, with a temperature range of –40 °C to +125 °C, and is offered in QFN, TSSOP, and QSOP packages.
| Maximum output current per port | 50 mA at 5.5 V |
|---|---|
| Supply voltage range | 2 V to 3.6 V |
| Operating temperature range | –40 °C to +125 °C |
| I²C/SMBus clock frequency | 400 kHz |
| Maximum number of I²C addresses | 64 |
| Standby current (typical) | 1.2 µA |
Each port can sink up to 50 mA at 5.5 V.
The device operates from 2 V to 3.6 V.
The MAX7315 can be configured to any of 64 possible I²C slave addresses.