5
DEMO MANUAL DC330
LOW DROPOUT REGULATOR
APPLICATIO S I FOR ATIO
W
U
U
U
5Hz SINGLE ORDER
HIGHPASS
IN
10Hz TO 100kHz
AN83 F01
GAIN = 60dB
10Hz 2nd ORDER
BUTTERWORTH HP
100kHz 4th ORDER
BUTTERWORTH LP
5Hz SINGLE ORDER
HIGHPASS
10
µ
F
R
LOAD
(TYPICALLY
100mA)
TYPICAL REGULATOR UNDER TEST
5V
OUT
EXTERNAL INPUT
–
+
A1
LT1028
100
Ω
330
µ
F
INPUT
3.16k
+
ALL RESISTORS 1% METAL FILM
4.7
µ
F CAPACITORS = MYLAR, WIMA MKS-2
330
µ
F CAPACITORS = SANYO OSCON
±
4.5V DERIVED FROM 6AA CELLS
POWER REGULATOR FROM APPROPRIATE
NUMBER OF D SIZE BATTERIES
+
–
+
A2
LT1028
100
Ω
6.19k
2k
5.9K
–
+
A3
LT1224
2.49k
4.99k
4.7
µ
F
4.5V
–4.5V
4.7
µ
F
NORMAL
INPUT
1
µ
F
V
IN
IN
OUT
SHDN
BYP
GND
LT1761-5
0.01
µ
F
100
Ω
OUTPUT TO THERMALLY RESPONDING
RMS VOLTMETER
0.1V FULL SCALE = 100
µ
V
RMS
NOISE
10Hz TO 100kHz BW
AN83 F02
330
µ
F
+
LTC1562
10k
5.62k
1
20
2
19
3
18
4
17
5
16
6
15
7
14
8
13
9
12
10
11
10k
–4.5V
–4.5V
4.5V
13k
17.8k
110k
43.2k
110k
10k
110k
110k
10k
Figure 3. Implementation of Figure 2. Low Noise Amplifiers Provide Gain and Initial
Highpass Shaping. LTC1562 Filter Supplies 4th Order Butterworth Lowpass Characteristic
Figure 2. Filter Structure for Noise Testing LDOs. Butterworth
Sections Provide Appropriate Response in Desired Frequency Range
Downloaded from
Downloaded from
Downloaded from
Downloaded from
Downloaded from
