Rainbow Electronics MAX1865 - Manual (Page 7)

MAX1864/MAX1865
xDSL/Cable Modem Triple/Quintuple Output
Power Supplies
_______________________________________________________________________________________ 7
Typical Operating Characteristics (continued)
(Circuit of Figure 1, V IN = 12V, V OUT = 3.3V, T A = +25°C, unless otherwise noted.)
2.50
0.01 1 0.1 100
POSITIVE LINEAR REGULATOR
OUTPUT VOLTAGE vs. LOAD CURRENT
(Q LDO = 2N3905)
2.42
2.44
2.46
2.48
MAX18664/65 toc10
LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
10 1000
V SUP(POS) = 5.0V
V SUP(POS) = 3.3V
2.42
2.44
2.46
2.48
2.50
2 4 3 5 6 7 8
POSITIVE LINEAR REGULATOR
OUTPUT VOLTAGE vs. SUPPLY VOLTAGE
(Q LDO = 2N3905)
MAX1864/65 toc11
SUPPLY VOLTAGE (V)
OUTPUT VOLTAGE (V)
I OUT2 = 1mA
I OUT2 = 100mA
80
70
60
50
40
30
20
10
0
0.1 10 100 1 1000
POSITIVE LINEAR REGULATOR
POWER-SUPPLY REJECTION RATIO
(Q LDO = 2N3905)
MAX1864/65 toc12
FREQUENCY (kHz)
PSRR (dB)
I OUT2 = 50mA
POSITIVE LINEAR REGULATOR
LOAD TRANSIENT
(Q LDO = 2W3905)
MAX1864/65 toc13
100mA
2.457V
2.467V
A. I OUTZ = 1mA TO 100mA, 50mA/div
B. V OUTZ = 2.5V, 5mV/div
C
LDO(POS)
= 10 µF CERAMIC, V
SUP(POS)
= 3.3V
CIRCUIT OF FIGURE 1
0
B
A
10 µs/div
2.50
0.01 0.1 1000 100
POSITIVE LINEAR REGUALTOR
OUTPUT VOLTAGE vs. LOAD CURRENT
(Q LDO = TIP30)
2.42
2.44
2.46
2.48 MAX1864/65 toc14
LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
1 10
V
SUP(POS)
= 5.0V
V SUP(POS) = 3.3V
2.42
2.44
2.46
2.48
2.50
2 4 6 8 10 12
POSITIVE LINEAR REGULATOR
OUTPUT VOLTAGE vs. SUPPLY VOLTAGE
(Q LDO = TIP30)
MAX1864/65 toc15
SUPPLY VOLTAGE (V)
OUTPUT VOLTAGE (V)
I OUT2 = 1mA
I OUT2 = 100mA