The Micro FlexDrive is a high-efficiency switching current
regulator that can be powered by battery combinations which result in
a Voltage of 2.0 – 5.5V DC (and up to 6.4VDC with a diode in
series). This includes 2-4 AAAs, AAs, Cs, Ds, and single lithium
batteries primary and rechargeable. The driver operates as a current
regulated source, varying the output voltage above and below the
battery voltage as necessary to meet the current output setting. In
operation, the driver will drain the power source until its voltage
reaches 2.0V and then will shut off. This, combined with the high
efficiency of the driver provides the maximum runtime possible for
portable lasers.
Current Setting:
The Micro FlexDrive has five output current ranges, listed in the diagram below. Each range listed in approximate,
there is variation from unit to unit so test the closest range to your desired current and work your way up or down
the scale. Removing the end resistor has the effect of decreasing the output current slightly when you are in ranges
2-4. The default 65-100mA range requires no changes. The other ranges require solder jumpers as shown, or the
end resistor to be removed (scraped off is OK) when there is an x on it. To adjust and set the diver current, a load is
required. A series of 3 or 4 1N4001 diodes and a 1 to 0.2 ohm resistor is recommended for use as a dummy load.
Use the Voltage across the dummt load resistor to determine current. Output current is adjusted via the
potentiometer trimmer. An insulated screwdriver and a light touch are recommended for adjustment.
Powering the driver:
If 6V or greater battery source is to be used, the input voltage must be dropped to no greater than 5.8VDC. For
example, if two Lithium primary CR123As are used, each with a maximum surface charge voltage of 3.2V, a
1N4000 series diode should be placed in series with the driver power input.
The FlexDrive V5 contains built-in battery reverse polarity protection.
The battery negative (-) connection and the diode – (cathode) connections are continuous. As such, if the battery –
is connected to the laser casing at the battery, and the laser diode cathode is connected to the casing as well, only the
diode cathode lead needs to be connected to the driver to complete the circuit for both battery (-) and diode (-)
connections.

download V5 User Manual