Yes, you read that project title right; this simple circuit will enable you to generate 5V DC from a single 1.5V DC AA battery. How can you pump 1.5V up to 5V, you ask? It's simple with a little piece of electronic steroids from MAXIM IC.
The MAX1674 IC is a DC-to-DC step-up converter that can take in voltages as low as .7V and crank out a digital circuit enriching 5V. Or, for more finicky projects, the MAX1674 can also output 3.3V. A simple pin-selectable preset determines the output voltage.
There is one small caveat with this project, however. Whether a blessing or a curse, the MAX1674 generates a steady-state output current ranging between 180-420 mA. Therefore, high current projects involving motors won't be able to benefit from this voltage amplifying circuit.
On the other hand, powering lightweight projects involving TTL/LS circuitry or LEDs are ideal applications for Voltoids. In fact, with such a low operating current, the MAX1674 is able to drive a 3.3V LED without the ubiquitous power-limiting resistor. All from a single 1.5V AA battery.
If this project seems beyond your talents, but the benefits of powering a digital circuit from a single 1.5V DC power source sounds enticing, you can opt to purchase a similar circuit from Spark Fun Electronics. Costing less than $10, this clever little device which is designed by Bodhilabs.com is housed discretely on the back of an AA battery holder.
Unfortunately, with this commercial product you are limited to a fixed 5V output and it isn't housed in a cool Altoids tin. Enter Voltoids.
Step 1: How to Build Voltoids
Time: 4 hours
- (1) MAX1674 (Digi-Key #MAX1674EUA+-ND; $5.06 NOTE: this is a uMax device)
- (2) .1mF ceramic capacitor (All Electronics #104D50; $1.00/10)
- (2) 47mF electrolytic capacitor (Electronics Goldmine #G13761; $1.00/20)
- (1) 100K resistor (Electronics Goldmine G497R; $3.50/100)
- (1) 22mH inductor (Digi-Key #308-1533-1-ND; $1.17 NOTE: this is an SMD)
- Or, try this 20mH inductor (Electronic Goldmine #G1325; $1.00/5)
- (1) rotary switch (Electronics Goldmine #G13928; $1.00/4)
- (1) knob (Electronics Goldmine #G14481; $.99)
- (1) Altoids tin (salvaged)
- (1) two-position header pins (BG Micro #ACS1019; $.33/2x17)
- (1) AA battery holder (Electronics Goldmine #G16152; $1.00)
- (1) small perforated prototyping board - optional
- (1) 8-pin uMax adapter prototyping board - optional