Key facts
- Brand
- Maxim
- Model
- MAX6650
- Industry
- Industrial
- Documents
- 2
- Languages
- EN
- Last added
- 2012-05-09
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MAXIM INTEGRATED PRODUCTS MAX6650/MAX6651 Fan-Speed Regulators Monitors with SMBus/I2C-Compatible Interface handbook
The MAX6650 and MAX6651 fan controllers use a 2‑wire SMBus/I²C‑compatible interface to regulate and monitor the speed of 5 VDC/12 VDC brushless fans with built‑in tachometers. They adjust fan voltage via an external MOSFET or bipolar transistor, forcing the tachometer frequency to match a programmed value.
Both devices provide general‑purpose I/O pins, selectable slave addresses, and optional hardware full‑on override. The MAX6650 supports a single fan, while the MAX6651 can monitor up to four fans and control them as a unit. Packages are a 10‑pin UMAX for the MAX6650 and a 16‑pin QSOP for the MAX6651.
Maxim MAX6650 specifications
| Supply Voltage (Vcc) | 3.0 V to 5.5 V |
|---|---|
| Supply Current (Full‑on mode) | 10 mA |
| Output Sink Current | 10 mA |
| Output Source Current | 50 mA |
| Operating Temperature Range | -40 °C to +85 °C |
| GPIO Sink Capability | 10 mA |
| Package Types | 10‑pin UMAX (MAX6650) / 16‑pin QSOP (MAX6651) |
All Maxim MAX6650 documents by type
Ratings, dimensions and ordering codes, for selection and design work.
Questions answered in these manuals
What communication interface do the MAX6650 and MAX6651 use?
They use a 2‑wire SMBus/I²C‑compatible interface for register access.
How many fans can the MAX6651 monitor simultaneously?
The MAX6651 can monitor up to four fans using its additional tachometer inputs.
What is the supply voltage range for the MAX6650/MAX6651?
The devices operate from 3.0 V to 5.5 V supply voltage.
What is the maximum operating temperature?
Both devices are rated for an operating temperature range of –40 °C to +85 °C.
