DESCRIPTION

· The SX1508B and SX1509B are ultra-low voltage GPIO expanders designed for low-power handheld battery-powered equipment.
· These devices support 8- and 16-channel configurations and expand I/O via a 400kHz I2C interface.
· They act as level shifters, connecting microcontrollers and components operating at different voltage levels.
· The core operates as low as 1.425V, with dual I/O banks operating independently between 1.2V and 3.6V (5.5V tolerant).
· Integrated LED driver supports intensity control (256-step PWM), blinking, and breathing effects.
· On-chip keypad scanning engine supports up to 64 keys without host interaction.
· Programmable interrupts and small footprint packages are available, operating from -40°C to +85°C.

FEATURES

· Dual independent I/O rails (VCC1, VCC2) enable direct level shifting between I/O banks and host controllers.
· 5.5V tolerant I/Os with up to 15mA output sink per pin.
· Integrated LED driver with 256-step PWM, 224 on/off values, and 224 fade in/out values.
· Keypad scanning engine supports 8x8 matrix (64 keys) with configurable input debouncer.
· 8/16 channels of true bidirectional I/O with programmable pull-up/pull-down and push/pull or open-drain outputs.
· Open-drain active low interrupt output (NINT) with bit masking and programmable edge sensitivity.
· Built-in clock management with internal 2MHz oscillator or external clock input.
· 400kHz I2C compatible slave interface with 4 user-selectable addresses.
· Ultra-low current consumption (1µA typical) and up to 2kV HBM ESD protection.
· Pb & halogen-free, RoHS/WEEE compliant.

APPLICATIONS

· Cell phones, PDAs, and MP3 players.
· Digital cameras, notebooks, and GPS units.
· Any battery-powered equipment requiring I/O expansion and level shifting.