AAT3216 Datasheet, PDF (12/16 Pages) List of Unclassifed Manufacturers – 150mA MicroPower™ LDO with PowerOK

AAT3216
150mA MicroPower™ LDO with PowerOK
sink area or by operating the LDO regulator in a
duty-cycled mode.
For example, an application requires V_IN = 4.2V
while V_OUT = 2.5V at a 150mA load and T_A = 85°C.
V_IN is greater than 3.90V, which is the maximum
safe continuous input level for V_OUT = 2.5V at
150mA for T_A = 85°C. To maintain this high input
voltage and output current level, the LDO regulator
must be operated in a duty-cycled mode. Refer to
the following calculation for duty-cycle operation:
I_GND = 150µA
I_OUT = 150mA
V_IN = 4.2V
V_OUT = 2.5V
%DC =
100
P_D(MAX)
(V_IN - V_OUT)I_OUT + (V_IN × I_GND)
%DC =
100
(4.2V
-
211mW
2.5V)150mA + (4.2V
×
150µA)
%DC = 85.54%
P_D(MAX) was assumed to be 211mW.
For a 150mA output current and a 2.7V drop across
the AAT3216 at an ambient temperature of 85°C,
the maximum on-time duty cycle for the device
would be 85.54%.
The following family of curves show the safe oper-
ating area for duty-cycled operation from ambient
room temperature to the maximum operating level.
Device Duty Cycle vs. V_DROP
(V_OUT = 2.5V @ 25°C)
3.5
3
2.5
2
1.5
1
0.5
0
0
200mA
10 20 30 40 50 60 70 80 90 100
Duty Cycle (%)
Device Duty Cycle vs. V_DROP
(V_OUT = 2.5V @ 50°C)
3.5
3
2.5
2
1.5
1
0.5
0
0
200mA
150mA
10 20 30 40 50 60 70 80 90 100
Duty Cycle (%)
Device Duty Cycle vs. V_DROP
(V_OUT = 2.5V @ 85°C)
3.5
3
2.5
2
1.5
1
0.5
0
0
200mA
150mA
100mA
10 20 30 40 50 60 70 80 90 100
Duty Cycle (%)
12
3216.2006.01.1.3