MIC5216_07 Datasheet, PDF (11/13 Pages) Micrel Semiconductor – 500mA-Peak Output LDO Regulator

Micrel, Inc.
MIC5216
a. 25°C Ambient
b. 50°C Ambient
c. 85°C Ambient
Figure 3. MIC5216-x.xBMM (MSOP-8) on Minimum Recommended Footprint
a. 25°C Ambient
b. 50°C Ambient
c. 85°C Ambient
Figure 4. MIC5216-x.xBMM (MSOP-8) on on 1-inch² Copper Cladding
The total power dissipation of the device under these
conditions is the sum of the two power dissipation
figures.
P_D(total) = P_D × 50mA + P_D × 500mA
P_D(total) = 151mW + 119mW
P_D(total) = 270mW
The total power dissipation of the regulator is less than
the maximum power dissipation of the SOT-23-5
package at room temperature, on a minimum footprint
board and therefore would operate properly.
Multilayer boards with a ground plane, wide traces near
the pads, and large supply-bus lines will have better
thermal conductivity.
For additional heat sink characteristics, please refer to
Micrel Application Hint 17, “Designing P.C. Board Heat
Sinks”, included in Micrel’s Databook. For a full
discussion of heat sinking and thermal effects on voltage
regulators, refer to Regulator Thermals section of
Micrel’s Designing with Low-Dropout Voltage Regulators
handbook.
Fixed Regulator Circuits
MIC5216
V_IN
IN OUT
EN FLG
GND
100k
V_OUT
1µF
Figure 5. Low-Noise Fixed Voltage Regulator
Figure 5 shows a basic MIC5216-x.xBMx fixed-voltage
regulator circuit. A 1µF minimum output capacitor is
required for basic fixed-voltage applications.
The flag output is an open-collector output and requires
a pull-up resistor to the input voltage. The flag indicates
an undervoltage condition on the output of the device.
March 2007
11
M9999-032307