10-Port, Constant-Current LED Driver and I/O Expander with PWM Intensity Control
Space-Saving, Constant-Current LED Driver with Reset
DescriptionThe MAX6946/MAX6947 I²C-/SMBus™-compatible, serial-interfaced peripherals provide microprocessors with 10 I/O ports rated to 7V.
Each port can be configured as a 2.5mA to 20mA constant-current LED driver (static or PWM), a 1.25mA to 10mA constant-current LED driver (static or PWM), an open-drain logic output, or an overvoltage-protected Schmitt logic input.
Analog and switching LED intensity control includes individual 8-bit PWM control per output, individual 1-bit analog current control (half/full scale) per output, and a global 3-bit DAC current control that applies to all LED outputs.
The MAX6946/MAX6947 can stagger the PWM timing of the 10-port outputs in consecutively phased 45° increments. Staggering the outputs spreads the PWM load currents over time in eight steps, helping to even out the power-supply current and reduce the RMS current.
For a similar part with an SPI™-/QSPI™-/ or MICROWIRE™-compatible interface, refer to the MAX6966/MAX6967 data sheet.
- 2.25V to 3.6V Operation
- I/O Ports Default to High Impedance (LEDs Off) on Power-Up
- I/O Port Inputs Are Overvoltage Protected to 7V
- I/O Port Outputs Are 7V-Rated Open-Drain, 10mA or 20mA Constant-Current Static/PWM LED Drivers, or Open-Drain Logic Outputs
- I/O Ports Support Hot Insertion
- Individual 8-Bit PWM Intensity Control for Each LED
- Active-Low RST Input Clears Serial Interface and Can Exit Shutdown (Warm Start)
- MAX6946 OSC Input Allows for External PWM Clock Input
- MAX6947 AD0 Input Selects from Two Slave Addresses
- Auto Ramp-Up Out of Shutdown, and Up to 4s Hold-Off Before Ramp-Down into Shutdown
- 0.8µA (typ) Shutdown Current
- -40°C to +125°C Temperature Range
- Tiny WLP Package (4 x 4 Grid)
- Cellular Phones
- Keypad Backlights
- LCD Backlights
- LED Status Indicators
- Portable Equipment
- RGB LED Drivers
|Part Number||Interface||I/O||Reset Input||Over Voltage Protection|
|MAX6946||Serial - I2C Compatible||-||Yes||7||20||2.25||3.6|
|Device||Fab Process||Technology||Sample size||Rejects||FIT at 25°C||FIT at 55°C||Material Composition|
- High Integration
- Low EMI
- I2C Control/Diagnostic Interface with FLTB (Interrupt) Output