MAX5486

The MAX5486 dual 40k logarithmic taper volume control features a debounced pushbutton up/down interface that controls volume and balance in audio applications. An integrated bias generator provides the required ((VDD + VSS)/ 2)bias voltage, eliminating the need for costly external op-amp circuits in unipolar audio applications. A mode-indicator LED output indicates volume or balance control. Five integrated LED drivers indicate volume level or balance settings, depending on the status of the mode indicator. Each potentiometer has 32 log-spaced tap points with a buffered wiper output to replace mechanical potentiometers. The MAX5486 advances the wiper setting once per button push. Maxim's proprietary SmartWiper control eliminates the need for a microcomputer to increase the wiper transition rate. The accelerated auto-advance feature provides a wiper-changing rate at 4Hz for holding the control input low for more than 250ms and at 8Hz after 500ms and then at 11Hz after 1000ms (see Table 2). Use the MAX5486 digital inputs with momentary contact single-pole/single-throw (SPST)pushbutton switches. Each input includes internal debounced circuitry and a pullup resistor to VLOGIC. The typical total harmonic distortion plus noise (THD+N)for the device is 0.003%. The MAX5486 provides a nominal temperature coefficient of 35ppm/°C end-to-end and 5ppm/°C ratiometrically and a nominal resistance of 40k per potentiometer. The MAX5486 is available in a 24-pin TSSOP package and is specified for operation over the -40°C to +85°C extended temperature range. All of the MAX5486's pushbutton inputs are debounced. The mute input allows a single pushbutton to change between volume control and the -90dB (typ)mute setting. The mode input toggles between volume and balance control. The click-and-pop suppression feature minimizes the audible noise generated by wiper transitions.

The features of MAX5486 can be summarized as (1)debounced pushbutton interface; (2)smartwiper control advances wiper rate; (3)low-power wiper buffers provide 0.003% THD+N; (4)bias generator eliminates external op amps; (5)five-segment LED volume/balance indicator; (6)clickless switching; (7)logarithmic taper volume control with (31)2dB steps; (8)Single +2.7V to +5.5V or Dual ±2.7V supply voltage Operation; (9)power-on reset to -12dBFwiper position; (10)MUTE function toggles to 90dB (typ); (11)low 1A shutdown supply current; (12)40k end-to-end fixed resistance value; (13)small, 24-pin TSSOP package.

The absolute maximum ratings of MAX5486 are (1)SHDN, MODE, MUTE, UP/BALL, and DN/BALR to GND: -0.3V to the lower of (VLOGIC + 0.3V and +6V); (2)H_, L_, W_, BIASCAP, BIAto GND: -0.3V to the lower of (VDD + 0.3V and +6V); (3)LEDIND_, MODEIND to GND: -0.3V to +6V; (4)VLOGIC to GND: -0.3V to +6V; (5)VDD to GND: -0.3V to +6V; (6)VDD to VLOGIC: -6V to +6V; (7)GND to VSS: -0.3V to +6V; (8)VDD to VSS: -0.3V to +6V; (9)average current into H_, L_, and W_: ±1mA; (10)maximum continuous current into H_, L_: ±4mA; (11)input and output latchup immunity: ±200mA; (12)continuous power dissipation (TA = +70°C)24-pin TSSOP (derate 8.3mW/°C above +70°C): 657mW; (13)operating temperature range: -40°C to +85°C; (14)storage temperature range: -60°C to +150°C; (15)maximum junction temperature: +150°C; (16)lead temperature (soldering, 10s): +300°C.