CAT6221
300 mA CMOS Dual LDO
Regulator
Description
The 300 mA CMOS Dual LDO CAT6221 combines in a single
TSOT23 6lead package two low dropout regulators (LDO), each
CAT6221
VIN
VOUT1
V
IN
EN1
LDO1
V
OUT1
EN1
Shutdown
Reference
Switch
VIN VIN VOUT1
VOUT1
2.3 V to 5.5 V C
C
IN OUT1
VOUT2
CAT6221 1 F
1 F
LDO2
EN2
V
OUT2
OFF
ON EN1
VOUT2 EN2
VOUT2
OFF
EN2
ON
GND
Shutdown
C
OUT2
Switch
1 F
GND
Figure 1. Typical Application Circuit Figure 2. CAT6221 Functional Block Diagram
Pin Function
VIN is the supply pin for the LDO. A small 1 F ceramic pins and ground. For better transient response, its value can
bypass capacitor is required between the V pin and ground be increased to 4.7 F.
IN
near the device. When using longer connections to the power The capacitor should be located near the device. For the
supply, C value can be increased without limit. The TSOT23 6lead package, a continuous 300 mA output
IN
operating input voltage range is from 2.3 V to 5.5 V. current for both LDOs may turnon the thermal protection.
On each output, a 250 internal shutdown switch
EN1 & 2 are the enable control logic (active high) for the
discharges the output capacitor in the noload condition.
regulator outputs.
GND is the ground reference for the LDO. The pin must be
VOUT1 & 2 are the LDO regulator outputs. A small 1F
connected to the ground plane on the PCB.
ceramic bypass capacitor is required between the VOUT
Table 1. ABSOLUTE MAXIMUM RATINGS
Parameter Rating Unit
V 0 to 6.5 V
IN
V , V 0.3 to V + 0.3 V
EN OUT IN
Junction Temperature, T +150 C
J
Power Dissipation, P Internally Limited (Note 1) mW
D
Storage Temperature Range, T 65 to +150 C
S
Lead Temperature (soldering, 5 sec.) 260 C
ESD Rating (Human Body Model) 3 kV
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
Table 2. RECOMMENDED OPERATING CONDITIONS (Note 2)
Parameter Range Unit
V 2.3 to 5.5 V
IN
V 0 to V V
EN IN
Junction Temperature Range, T 40 to +125 C
J
Package Thermal Resistance (TSOT23), 235 C/W
JA
NOTE: Typical application circuit with external components is shown above.
1. The maximum allowable power dissipation at any T (ambient temperature) is P = (T T )/ . Exceeding the maximum allowable
A Dmax Jmax A JA
power dissipation will result in excessive die temperature, and the regulator will go into thermal shutdown.
2. The device is not guaranteed to work outside its operating rating.