
Low Dropout
Linear
Regulator
Fixed and
Adjustable Output
FEATURES
·
Fixed
5V to 2.9V (LR529, LR5D2).
·
Fixed
5V to 3.3V (LR533, LR5D3).
·
Fixed
5V to 3.9V (LR539, LR5D9).
·
Output
Current Rating 1A, 2A, or 3A.
·
Adjustable
Output 2.5V to 4.5V (LR5254).
·
Low
Off State Current.
·
Low
Dropout Voltage.
·
On-Chip
Thermal Limiting.
·
On-Chip
Short Circuit Protection.
·
TO-220
3 or 5 pins or TO-252 Packages.

The LR53X are low dropout three
terminal regulators specifically designed for 5V input and fixed 2.9V, 3.3V,
and 3.9V output, respectively. LR5254 is a five terminal regulator specifically
designed for 5V input and adjustable 2.5V to 4.5V output. These regulators have
current ratings of 1A, 2A, and 3A grades. They are identified by dash numbers.
These regulators are optimized
for low voltage applications where transient response and low ripple noise are critical.
On Chip thermal limiting and short circuit shut off provide protection against
any combination of over-load that would create excessive junction temperatures.
LR5254 may be powered down by
pulling EN pin low. Its output voltage is adjustable through ADJ pin. See
Figure 1 for detail.
Vout=Vref x (1+R2/R1); Vref is about 1.25V .
ORDERING
INFORMATION
ELECTRICAL SPECIFICATIONS
|
Absolute Maximum Ratings |
||
|
|
Input Voltage |
Vin= 6.0V |
|
|
Voltage at any Pin |
Vss-.3V to Vdd+.3V |
|
|
Operating Temperature |
Ta=0°C
to 125°C |
|
|
Storage Temperature |
-50°C
to 150°C |
|
|
Lead Temperature |
300°C
(10 Second) |
|
Parameters |
Min. |
Nom |
Max. |
Unit |
Condition |
|
Tj Junction Temp |
|
|
125 |
°C |
|
|
Vin Input Voltage |
4.75 |
5.00 |
5.25 |
V |
|
|
Vout Output Voltage |
2.81 |
2.9 |
2.99 |
V |
LR529-2, -3, LR5D2 |
|
|
3.21 |
3.3 |
3.39 |
V |
LR533-2, -3, LR5D3 |
|
|
3.81 |
3.9 |
3.99 |
V |
LR539-2, -3, LR5D9 |
|
|
2.5 |
|
4.5 |
V |
LR5254 |
|
Iout Output Current |
|
2.0 |
|
A |
LR529-2, LR533-2 |
|
|
|
1.0 |
|
A |
LR5D2, LR5D3 |
|
|
|
3.0 |
|
A |
LR529-3, LR533-3 |
|
|
|
1.0 |
|
A |
LR539-2, LR5D9 |
|
|
|
1.5 |
|
A |
LR539-3 |
|
|
0.5 |
|
3.5 |
A |
LR5254 |
|
Viod Dropout Voltage |
0.2 |
|
|
V |
|
|
Iq Quiescent Current |
|
5.0 |
|
mA |
Iout=0 |
|
Ioff Off State Current |
|
5.0 |
|
uA |
EN=Vil |
|
RegL Load Regulation |
|
0.1 |
0.5 |
% |
|
|
RegI Line Regulation |
|
0.05 |
0.2 |
% |
|
|
RR Ripple Rejection |
|
60 |
|
dB |
f=120Hz |
|
Tc Temperature Coef. |
|
±1 |
|
% |
|
|
Vil Input Low |
|
|
0.8 |
V |
EN pin. |
|
Vih Input High |
2.0 |
|
|
V |
EN pin. |

|
Ordering Information |
|||
|
Part # |
Output |
Amps |
Package |
|
LR529-2 |
2.9V |
2A |
TO-220/3 |
|
LR5D2 |
|
1A |
TO-252 |
|
LR529-3 |
|
3A |
TO-220/3 |
|
LR533-2 |
3.3V |
2A |
TO-220/3 |
|
LR5D3 |
|
1A |
TO-252 |
|
LR533-3 |
|
3A |
TO-220/3 |
|
LR539-2 |
3.9V |
1A |
TO-220/3 |
|
LR5D9 |
|
1A |
TO-252 |
|
LR539-3 |
|
1.5A |
TO-220/3 |
|
LR5254 |
2.5-4.5V |
* |
TO-220/5 |
* See Figure
2 for output current value.

![]()