MAX5478
Dual, 256-Tap, Nonvolatile, I²C-Interface, Digital Potentiometers
Industry's Smallest, Dual, 256-Tap Digital Potentiometers Fit in 3mm x 3mm TQFN
Maxim Confidential 
MyMaxim SubscriptionsProduct Details
Key Features
Applications/Uses
| Steps | 256 |
| # Potentiometers | 2 |
| Control Interface | 2-Wire Serial |
| Taper | Linear |
| Wiper Memory | Non-Volatile |
| REND-TO-END (kΩ) | 50 |
| Res. Tol. (%) | 25 |
| Temp. Coeff. (ppm/°C) (typ) | 35 |
| Wiper Resistance (Ω) (typ) | 325 |
| ICC @5V (µA) (max) | 1 |
| Package/Pins | TQFN/16 TSSOP/14 |
| Budgetary Price (See Notes) | 2.11 |
Simplified Block Diagram
Technical Docs
| Data Sheet | Dual, 256-Tap, Nonvolatile, I²C-Interface, Digital Potentiometers | Jan 30, 2012 | |
| App Note | Logging the Linear Digital Potentiometer | ||
| App Note | Using an Analog Voltage to Control a Digital Potentiometer |
Support & Training
Search our knowledge base for answers to your technical questions.
Filtered SearchOur dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal .
Parameters
| Steps | 256 |
| # Potentiometers | 2 |
| Control Interface | 2-Wire Serial |
| Taper | Linear |
| Wiper Memory | Non-Volatile |
| REND-TO-END (kΩ) | 50 |
| Res. Tol. (%) | 25 |
| Temp. Coeff. (ppm/°C) (typ) | 35 |
| Wiper Resistance (Ω) (typ) | 325 |
| ICC @5V (µA) (max) | 1 |
| Package/Pins | TQFN/16 TSSOP/14 |
| Budgetary Price (See Notes) | 2.11 |
Key Features
- Power-On Recall of Wiper Position from Nonvolatile Memory
- EEPROM Write Protection
- Tiny 3mm x 3mm x 0.8mm Thin QFN Package
- 70ppm/°C End-to-End Resistance Temperature Coefficient
- 10ppm/°C Ratiometric Temperature Coefficient
- Fast 400kbps I²C-Compatible Serial Interface
- 1µA (max) Static Supply Current
- Single-Supply Operation: +2.7V to +5.25V
- 256 Tap Positions per Potentiometer
- ±0.5 LSB DNL in Voltage-Divider Mode
- ±1 LSB INL in Voltage-Divider Mode
Applications/Uses
- Liquid-Crystal Display (LCD) Contrast Control
- Low-Drift Programmable-Gain Amplifiers
- Mechanical Potentiometer Replacements
- Volume Control
Description
The MAX5477/MAX5478/MAX5479 nonvolatile, dual, linear-taper, digital potentiometers perform the function of a mechanical potentiometer, but replace the mechanics with a simple 2-wire digital interface. Each device performs the same function as a discrete potentiometer or variable resistor and has 256 tap points.
The devices feature an internal, nonvolatile EEPROM used to store the wiper position for initialization during power-up. A write-protect feature prevents accidental overwrites of the EEPROM. The fast-mode I²C-compatible serial interface allows communication at data rates up to 400kbps, minimizing board space and reducing interconnection complexity in many applications. Three address inputs allow a total of eight unique address combinations.
The MAX5477/MAX5478/MAX5479 provide three nominal resistance values: 10kΩ (MAX5477), 50kΩ (MAX5478), or 100kΩ (MAX5479). The nominal resistor temperature coefficient is 70ppm/°C end-to-end and 10ppm/°C ratiometric. The low temperature coefficient makes the devices ideal for applications requiring a low temperature- coefficient variable resistor, such as low drift, programmable gain-amplifier circuit configurations.
The MAX5477/MAX5478/MAX5479 are available in 16-pin 3mm x 3mm x 0.8mm TQFN and 14-pin 4.4mm x 5mm TSSOP packages. These devices operate over the extended -40°C to +85°C temperature range.Technical Docs
| Data Sheet | Dual, 256-Tap, Nonvolatile, I²C-Interface, Digital Potentiometers | Jan 30, 2012 | |
| App Note | Logging the Linear Digital Potentiometer | ||
| App Note | Using an Analog Voltage to Control a Digital Potentiometer |
Support & Training
Search our knowledge base for answers to your technical questions.
Filtered SearchOur dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal .
Request a Quote