QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 813 HIGH VOLTAGE MICROPOWER VOLTAGE REGULATOR LT3013 DESCRIPTION Demonstration circuit 813 is a high voltage micro- tors, because of its ability to maintain stability with power voltage regulator using the LT3013 low drop- ceramic output capacitors. Due to its high input volt- out linear regulator, which comes in a low-profile 12- age range, the DC813 voltage regulator is ideally pin DFN package. DC813 has an input voltage range suited for automotive and industrial applications. from 3V to 80V, an output voltage range between Design files for this circuit board are available. Call 1.24V and 60V, and is capable of delivering 250 mA the LTC factory. max. The DC supply current is typically only 1 uA in LTC is a trademark of Linear Technology Corporation shutdown. DC813 is installed with ceramic capaci- QUICK START PROCEDURE DC813 is easy to set up to evaluate the performance Note: Be aware of the power dissipated by the of the LT3013. For proper measurement equipment LT3013, due to its high input voltage capabil- configuration, set up the circuit according to the dia- ity. Consequently, take care to stay under the gram in Figure 1. maximum junction temperature, 125 deg.C, when operating the LT3013. Please follow the procedure outlined below for proper 4. Insert the jumper JP1 shunt into the OFF posi- operation. tion and move the shunt in jumper JP2 into 1. Before proceeding to test, insert a shunt into the 5V output voltage option, and repeat the the OFF position of jumper JP1, and insert a test. Re-insert jumper JP1 shunt into the ON shunt into jumper JP2, the 3.3V option. position. Just as in the 3.3 Vout test, the 5V 2. Apply 5V across Vin (to GND). Insert the output voltage should read Vout +/- 2.5% tol- jumper JP1 shunt into the ON position. Draw erance under static line and load conditions, 1 mA of load current. Measure Vout it should and +/- 5% tolerance under dynamic line and be 3.3V +/- 2.5% (3.21V to 3.39V). load conditions. 3. Vary the input voltage from 5V to 80V and the 5. When finished evaluating, insert jumper JP1 load current from no load to 250 mA. Vout shunt into the OFF position. should measure 3.3V +/- 5% (3.13V to 3.47V). Warning - If long leads are used to power the demo circuit, the input voltage at the part could ring. This ring- ing could affect the operation of the circuit or even exceed the maximum voltage rating of the IC. To eliminate this, insert a small aluminum electrolytic capacitor (for instance, a Sanyo cap., part 100CV10BS) on the pads between the input power and return terminals on the bottom of the demo board. The (greater) ESR of the alu- minum electrolytic capacitor will dampen the (possible) ringing voltage due to the use of long input leads. On a normal, typical PCB, with short traces, the capacitor is not needed. 1 QUICK START GUIDE FOR DEMONSTRATION CIRCUIT 813 HIGH VOLTAGE MICROPOWER VOLTAGE REGULATOR Figure1. Proper Measurement Equipment Setup Figure 2. Measuring Input or Output Voltage Ripple 2