ADP3301AR-32 Analog Devices, ADP3301AR-32 Datasheet - Page 7

• Manufacturer Part Number: ADP3301AR-32
• Description: High Accuracy anyCAP 100 mA Low Dropout Linear Regulator
• Manufacturer: Analog Devices

It is not recommended to use solder mask or silkscreen on the
PCB traces adjacent to the ADP3301’s pins since it will increase
the junction to ambient thermal resistance of the package.
Shutdown Mode
Applying a TTL high signal to the shutdown pin, or tying it to
the input pin, will turn the output ON. Pulling the shutdown
pin low, or tying it to ground, will turn the output OFF. In
shutdown mode, quiescent current is reduced to less than 1 A.
Error Flag Dropout Detector
The ADP3301 will maintain its output voltage over a wide
range of load, input voltage and temperature conditions. If, for
example, regulation is lost by reducing the supply voltage below
the combined regulated output and dropout voltages, the ERRor
flag will be activated. The ERR output is an open collector,
which will be driven low.
Once set, the ERRor flag’s hysteresis will keep the output low
until a small margin of operating range is restored either by
raising the supply voltage or reducing the load.
APPLICATION CIRCUITS
Crossover Switch
The circuit in Figure 21 shows that two ADP3301s can be used
to form a mixed supply voltage system. The output switches
between two different levels selected by an external digital input.
Output voltages can be any combination of voltages from the
Ordering Guide.
Higher Output Current
The ADP3301 can source up to 100 mA without any heatsink
or pass transistor. If higher current is needed, an appropriate
pass transistor can be used, as in Figure 22, to increase the
output current to 1 A.
Step-Up/Step-Down Post Regulator
The circuit in Figure 23 provides a high precision, low dropout
regulated output voltage. It significantly reduces the ripple from
a switching regulator. The ADP3000 used in this circuit is a
switching regulator in the step-up configuration.
REV. 0
V
IN
= 2.5V TO 3.5V
100µF
10V
C1
I
LIM
Figure 23. Step-Up/Step-Down Post Regulator
ADP3000-ADJ
R1
120
GND
V
IN
SW2
6.8µH
L1
SW1
FB
1N5817
D1
–7–
C2
100µF
10V
V
V
IN
IN
OUTPUT SELECT
5V
0V
= 6V TO 8V
= 5.5V TO 12V
Figure 22. High Output Current Linear Regulator
R2
19.6k
1%
R3
10k
1%
*AAVID531002 HEAT SINK IS USED
47µF
C1
Figure 21. Crossover Switch
IN
ADP3301-3.3
1.0µF
C1
GND
+
50
R1
SD
ADP3301-5
OUT
IN
SD
IN
SD
ADP3301-5.0
ADP3301-3.3
MJE253*
GND
IN
GND
GND
ERR
OUT
C3
2.2µF
OUT
OUT
3.3V @ 100mA
+
C2
10µF
ADP3301
C2
0.47µF
V
V
OUT
OUT
= 5V @ 1A
= 5V/3.3V