OTHER LDO REGULATORS
2. To predict the output voltage at 10% load take the mea-
sured or specified voltage at 75% load and multiply by
(1 + Load Reg 10% to 75%). For example a DCP010505P
typical VOUT at 10% load will be 5V x (1 + 17%) = 5.85V.
The SGS-Thomson L4940V5 LDO can also be used to post
regulate the 5VOUT DCP010505 and can deliver a regulated
minimum 4.75V up to 135mA.
3. To predict the output voltage at 25% load on higher VOUT
versions take the measured or specified voltage at 75%
load and multiply by (1 + Load Reg 25% to 75%). For
example a DCP010512P typical VOUT at 25% load will be
12V x (1 + 12%) = 13.4V. To then estimate the voltage at
10% load take the previously calculated VOUT at
25% load and multiply by (1 + Load Reg 10% to 25%).
In this case the typical VOUT at 10% load will be 13.4V x
(1 + 7%) = 14.3V.
The 5VOUT DCP010505 can also be post regulated with the
Micrel MIC5207 which offers up to 180mA output drive
with a typical dropout voltage of 165mV at 150mA. The
MIC5207 is available in a micro-sized SOT23-5 package
which gives the minimum additional board area for post
regulation.
PREDICTING OUTPUT VOLTAGE VERSUS LOAD
The Load Regulation specifications are calculated as fol-
lows:
To obtain predictions for loads other than those specified
assume the VOUT versus load characteristic is linear between
the load points and calculate accordingly. The 10% to 100%
load specification guarantees the maximum voltage excursion
for any load between 10% to 100% with respect to VOUT at
75% load.
CONDITION
CALCULATION
10% to 100% Load
10% to 25% Load
10% to 75% Load
75% to 100% Load
(VOUT at 10% load – VOUT at 100% load)/ VOUT at 75% load
(VOUT at 10% load – VOUT at 25% load)/VOUT at 25% load
(VOUT at 10% load – VOUT at 75% load)/VOUT at 75% load
(VOUT at 75% load – VOUT at 100% load)/ VOUT at 75% load
The above does not take into consideration line regulation and
assumes a nominal input voltage. The 1:1 line regulation of the
DCP01 family means that a percentage change in the input
will give a corresponding percentage change in the output.
1. To predict the output voltage at 100% load take the mea-
sured or specified voltage at 75% load and multiply by
(1 + Load Reg 75% to 100%). For example a DCP010505P
typical VOUT at 100% load will be 5V x (1 – 8%) = 4.6V.
Output
Error
4
3
2
1
5
6
7
8
6
VIN
1
330kΩ
DCP
0105
LP2986
2.2µF
Load
2
5
0.47µF
+
4.7µF
0V
Com
FIGURE 10. Post Regulation of DCP010505P.
15.24 (0.600)
11.8 (0.464)
1.9 (0.075)
2.54 (0.100)
14-Pin
1.2 (0.047)
All Leads on 2.54mm Pitch
Dimensions in mm (inches)
FIGURE 11. PCB Pad Size and Placement for “U” Package.
17
®
DCP0105
BB [ BURR-BROWN CORPORATION ]
