Datasheet

P
D
+
ǒ
V
I
* V
O
Ǔ
I
O
P
D(max)
+
T
J
max * T
A
R
qJA
C1
0.1 µF
OUT
4
3
IN
NC
GND
2
5
V
I
V
O
0.47 µF
1
NC/FB
TPS71501-Q1
TPS71525-Q1, TPS71530-Q1
TPS71533-Q1, TPS71550-Q1
www.ti.com SGLS272G –OCTOBER 2004–REVISED JULY 2013
APPLICATION INFORMATION
The TPS715xx family of LDO regulators has been optimized for ultra-low power applications such as the
MSP430 microcontroller. Its ultralow supply current maximizes efficiency at light loads and its high input voltage
range makes it suitable for supplies such as unconditioned solar panels.
Figure 15. Typical Application Circuit (Fixed Voltage Version)
External Capacitor Requirements
Although not required, a 0.047-μF or larger input bypass capacitor, connected between IN and GND and located
close to the device, is recommended to improve transient response and noise rejection of the power supply as a
whole. A higher-value input capacitor may be necessary if large, fast-rise-time load transients are anticipated and
the device is located several inches from the power source.
The TPS715xx requires an output capacitor connected between OUT and GND to stabilize the internal control
loop. Any capacitor (including ceramic and tantalum) ≥0.47 μF properly stabilizes this loop.
Power Dissipation and Junction Temperature
To ensure reliable operation, worst-case junction temperature should not exceed 125°C. This restriction limits the
power dissipation the regulator can handle in any given application. To ensure the junction temperature is within
acceptable limits, calculate the maximum allowable dissipation, P
D(max)
, and the actual dissipation, P
D
, which
must be less than or equal to P
D(max)
.
The maximum-power-dissipation limit is determined using the following equation:
(1)
where:
T
J
max = Maximum allowable junction temperature
R
θJA
= Thermal resistance junction-to-ambient for the package (see the Dissipation Ratings table)
T
A
= Ambient temperature
The regulator dissipation is calculated using:
(2)
Power dissipation resulting from quiescent current is negligible.
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Product Folder Links: TPS71501-Q1 TPS71525-Q1 TPS71530-Q1 TPS71533-Q1 TPS71550-Q1