APL1541-33KC-TR ANPEC [Anpec Electronics Coropration], APL1541-33KC-TR Datasheet - Page 9

• Manufacturer Part Number: APL1541-33KC-TR
• Description: 1A Low Dropout Fast Response Positive Adjustable Regulator and Fixed 3.3V
• Manufacturer: ANPEC [Anpec Electronics Coropration]

Aluminum electrolytics can also be used, as long as
the ESR of the capacitor is <1 . The value of the
output capacitor can be increased without limit. Higher
capacitance values help to improve transient response
and ripple rejection and reduce output noise.
APL1541 has thermal protection which limits junction
temperature to 150°C. However, device functionality
is only guaranteed to a maximum junction tempera-
ture of +125°C. The thermal resistance for each ap-
plication will be affected by thermal interactions with
other components on the board. Some experimenta-
tion will be necessary to determine the actual value.
The power dissipation of APL1541 is equal to :
The curves for Ripple Rejection were generated using
an adjustable device with the adjust pin bypassed.
With a 22 F bypassing capacitor 75dB ripple rejec-
tion is obtainable at any output level. The impedance
of the adjust pin capacitor, at the ripple frequency,
should be < R1. R1 is normally in the range of 100 -
200 . The size of the required adjust pin capacitor is
a function of the input ripple frequency. At 120Hz,
with R1=100 , the adjust pin capacitor should be
13 F. For fixed voltage devices, and adjustable de-
vices without an adjust pin capacitor, the output ripple
will increase as the ratio of the output voltage to the
reference voltage (V
OUT
/V
REF
).
P
Maximum junction temperature is equal to :
T
Note: T
JUNCTION
D
= (V
IN
JUNCTION
= T
- V
OUT
AMBIENT
must not exceed 125°C
) x I
+ (P
OUT
D
x
JA
)