MAX6620ATI+

The MAX6620ATI+ is a quad linear fan-speed controller in 28 pin TQFN package. It controls the speeds of up to four fans using four independent linear voltage outputs. The drive voltages for the fans are controlled directly over the I2C interface. Each output drives the base of an external bipolar transistor or the gate of a FET in high-side drive configuration. Voltage feedback at the fan’s power supply terminal is used to force the correct output voltage. It offers two methods for fan control. In RPM mode, IC monitors four fan tachometer logic outputs for precise (±1%) control of fan RPM and detection of fan failure. In DAC mode, each fan is driven with a voltage resolution of 9bits and the tachometer outputs of the fans are monitored for failure. It is used in storage equipment and servers.

• Supply voltage range is 3V to 5.5V
• Operating temperature range from -40°C to 125°C
• Controls up to four independent fans with linear (DC) drive
• Uses four external low-cost pass transistors
• 1% accuracy precision RPM control
• Controlled voltage rate of change for best acoustics
• I2C bus interface
• 250µA (typ) operating supply current
• 3µA (typ) shutdown supply current

Applications

Motor Drive & Control

Notes

ADI products are only authorized (and sold) for use by the customer and are not to be resold or otherwise passed on to any third party