The MAX6615/MAX6616 is a temperature sensor that monitors two temperature channels. It can be used to monitor the internal chip temperature and the temperature of an external thermistor, or the temperatures of two external thermistors. The temperature data controls a PWM output signal to adjust the speed of a cooling fan, thereby minimizing noise when the system is running cool, but providing maximum cooling when power dissipation increases. The fans’ tachometer output signals are monitored by the MAX6615/MAX6616 to detect fan failure. If a fan failure is detected, the FAN_FAIL output is asserted. The 2-wire serial interface accepts standard system management bus (SMBusTM) write byte, read byte, send byte, and receive byte commands to read the temperature data and program the alarm thresholds. The programmable alarm output can be used to generate interrupts, throttle signals, or overtemperature shut- down signals. The MAX6616 features six GPIOs to provide additional flexibility. All of the GPIOs power-up as inputs, with the exception of GPIO0, which powers up as either an input or an output as determined by connecting the PRESET pin to ground or VCC. The MAX6616 is available in a 24-pin QSOP package, while the MAX6615 is available in a 16-pin QSOP pack- age. Both devices operate from a single-supply voltage range of 3.0V to 5.5V, have operating temperature ranges of -40°C to +125°C, and consume just 500µA of supply current. The device can be applied to desktop computers, servers, power supplies, and network equipment.
The MAX6615 and MAX6616 are dual‑channel temperature monitoring ICs that can read an internal die sensor and up to two external thermistors. Temperature data is used to drive two open‑drain PWM outputs for fan‑speed control, with optional over‑temperature (OT) and fan‑failure (FAN_FAIL) alarms.
Both devices operate from a single‑supply voltage of 3.0 V to 5.5 V, consume low power (typical 500 µA), and are available in 16‑pin (MAX6615) or 24‑pin (MAX6616) QSOP packages. The MAX6616 adds six configurable GPIOs. Communication is via a standard 2‑wire SMBus/I²C‑compatible interface supporting write, read, send, and receive byte commands.
| Operating Supply Voltage (VCC) | 3.0 V – 5.5 V |
|---|---|
| Standby Current (interface inactive) | 10 µA |
| Operating Current (ADC active) | 0.5 mA – 1 mA |
| Temperature Range | -40 °C to +125 °C |
| GPIO Count (MAX6616) | 6 |
| Fan‑Failure Output Name | FAN_FAIL |
| SMBus Addresses | 9 programmable addresses |
The devices operate from a single‑supply voltage of 3.0 V to 5.5 V.
The MAX6616 provides six configurable GPIO pins.
The fan‑failure output is labeled FAN_FAIL.
Both parts operate from –40 °C to +125 °C.