The U3V70x boost (step-up) voltage regulators are high-current, high-efficiency synchronous switching regulators that generate higher output voltages from input voltages as low as 2.9 V. The regulators actively limit the instantaneous input currents to 10 A, and the input current can typically be as high as 8 A for several seconds before the thermal protection activates. Input currents of around 6 A can typically be maintained for many minutes without triggering thermal shutdown, though the actual performance depends on depending on the input and output voltages as well as external factors such as ambient temperature and airflow. For boost regulators, the output current equals the input current times the efficiency times the ratio of VIN to VOUT, so the more you are boosting, the lower the maximum output current will be (see the Typical efficiencies and output currents section below for performance graphs).
These regulators feature a variety of built-in protections, including reverse voltage protection to keep your load safe in the event power is accidentally connected backward, and unlike most boost regulators, these units offer a true shutdown option that turns off power to the load (with typical boost regulators, the input voltage will pass directly through to the output when they are disabled).
The U3V70x family includes six versions with fixed output voltages ranging from 5 V to 15 V as well as an adjustable version that can be set anywhere between 4.5 V and 20 V using a precision 11-turn potentiometer:
- U3V70F5: Fixed 5V output
- U3V70F6: Fixed 6V output
- U3V70F7: Fixed 7.5V output
- U3V70F9: Fixed 9V output
- U3V70F12: Fixed 12V output
- U3V70F15: Fixed 15V output
- U3V70A: Precision-adjustable 4.5 – 20 V output
Features and specifications
- Input voltage: 2.9 V to 5 V
- Output voltage: 5 V with 4% accuracy
- True shutdown option turns off power to the load
- Typical efficiency of 80% to 95%, depending on input voltage and load (see the Typical efficiencies and output currents section below for performance graphs)
- 10 A switch allows for:
- Instantaneous input currents up to 10 A
- Input currents up to 8 A for several seconds
- Input currents up to 7 A for prolonged durations
- low quiescent current (see the quiescent current graph below for more details)
- Integrated protections:
- Reverse voltage protection
- Short-circuit protection with hiccup recovery
- Over-temperature shutoff
- Under-voltage lockout (typical thresholds are 2.4 V falling, 2.8 V rising)
- Cycle-by-cycle input current limiting to 10 A
- Compact size: 1.6″ × 0.6″ × 0.18″ (40.6 × 15.2 × 4.6 mm)
- Weight: 3.5 g
- Two mounting holes for #2 or M2 screws
- Smaller holes for 0.1″ header pins and larger holes for terminal blocks offer several options for connecting to the board
The different versions of the board all look very similar, so the bottom silkscreen includes a blank space where you can add your own distinguishing marks or labels.
The input voltage, VIN, must be at least 2.9 V and should not exceed the output voltage, VOUT. (If VIN is higher than VOUT, the higher input voltage will show up on the output, which is potentially dangerous for your connected load and could also damage the regulator.)
The regulator is enabled by default: a 100 kΩ pull-up resistor on the board connects the ENABLE pin to reverse-protected VIN. The ENABLE pin can be driven low (under 0.4 V) to turn off power to the load and put the board into a low-power state. The typical no-load quiescent current is less than 1 mA (see the quiescent current graph below for more details).
