MAX6946

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 RMcurrent. For a similar part with an SPITM-/QSPITM-/ or MICROWIRETMcompatible interface, refer to the MAX6966/MAX6967 data sheet. 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. The MAX6946/MAX6947 I2C-/SMBusTM-compatible, serial-interfaced peripherals provide microprocessors with 10 I/O ports rated to 7V.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 features of MAX6946 can be summarized as (1)2.25V to 3.6V operation; (2)I/O ports default to high impedance (LEDs Off)on power-up; (3)I/O port inputs are overvoltage protected to 7V; (4)I/O port outputs are 7V-rated open-drain, 10mA or 20mA constant-current static/PWM LED drivers, or open-drain logic outputs; (5)I/O ports support hot insertion; (6)individual 8-Bit PWM intensity control for each LED; (7)RST input clears serial interface and can exit shutdown (warm start); (8)MAX6946 OSC input allows for external PWM clock input; (9)MAX6947 AD0 input selects from two slave addresses; (10)auto ramp-up out of shutdown, and up to 4s hold-off before ramp-down into shutdown; (11)0.8A (typ)shutdown current; (12)-40°C to +125°C temperature range; (13)tiny WLP package (4 x 4 Grid).

The absolute maximum ratings of MAX6946 are (1)VDD to GND: -0.3V to +4V; (2)SCL, SDA, AD0, RST, OSC to GND: -0.3V to +6V; (3)P0 to P9 to GND: -0.3V to +8V; (4)DC current into P0 to P9: 24mA; (5)DC current into SDA: 10mA; (6)RST sink current: 10mA; (7)Total GND current: 280mA; (8)continuous power dissipation (TA = +70°C)16-Pin TQFN (derate 14.7mW/°C over +70°C): 1176mW/ 16-Bump WLP (derate 13.3mW/°C over +70°C): 1066mW; (9)operating temperature range (TMIN, TMAX): -40°C to +125°C; (10)junction temperature: +150°C; (11)storage temperature range: -65°C to +150°C; (12)lead temperature (soldering, 10s): +300°C.