LTM8057
6
8057f
For more information www.linear.com/LTM8057
Minimum Required Load
vs Input Voltage
TYPICAL PERFORMANCE CHARACTERISTICS
Typical Output Ripple
100mA Output Current, V
IN
= 12V
DC1988 V
OUT1
Start-Up Behavior
for Different C
SS
Values
Typical Switching Frequency vs
Output Current Stock DC1988A
Unless otherwise noted, operating conditions are
as in Table 1 (T
A
= 25°C).
INPUT VOLTAGE (V)
0
*SEE APPLICATIONS INFORMATION SECTION
FOR DISCUSSION OF 12V
OUT
MINIMUM LOAD
0
MINIMUM REQUIRED LOAD (mA)
5
10
15
20
25
5
10 15 20
8057 G19
25 30
V
OUT1
= 8V
V
OUT1
= 12V*
BIAS = 5V FOR V
IN
≥ 5V
BIAS = V
IN
FOR V
IN
< 5V
5mV/DIV
500ns/DIV
MEASURED ON DC1987 WITH ADDIONAL 1µF
AND BNC ATTACHED TO OUTPUT TERMINALS.
C7 = 0.1µF. USED HP461A 150MHz AMPLIFIER,
SET TO 40dB GAIN.
8057 G20
1V/DIV
C
SS
= 0.01µF
C
SS
= 0.1µF
NO C
SS
200µs/DIV
100mA RESISTIVE LOAD
8057 G21
OUTPUT CURRENT (mA)
0
0
SWITCHING FREQUENCY (kHz)
100
300
400
500
100
200
250
900
5V
IN
12V
IN
8057 G22
200
50 150
600
700
800
Input Current
vs V
IN,
V
OUT
Shorted
Junction Temperature Rise
vs Load Current
V
IN
(V)
INPUT CURRENT (mA)
80
70
60
20
40
10
30
50
0 12 3220 28241684
Maximum Output Current vs V
IN
Minimum Required Load
vs Input Voltage
INPUT VOLTAGE (V)
0
MAXIMUM REQUIRED LOAD (mA)
25
30
35
40
8057 G18
20
15
10
0
10
20
30
5
45
40
V
OUT
= 2.5V
V
OUT
= 3.3V
V
OUT
= 5V
BIAS = 5V FOR V
IN
≥ 5V
BIAS = V
IN
FOR V
IN
< 5V
V
IN
(V)
0
0
MAXIMUM OUTPUT CURRENT (mA)
100
200
300
400
5 10 15 20
8057 G17
25 30
V
OUT
= 8V
V
OUT
= 12V
BIAS = 5V FOR V
IN
≥ 5V
BIAS = V
IN
FOR V
IN
< 5V
V
OUT
LOAD CURRENT (mA)
TEMPERATURE RISE (°C)
8
4
6
0
5
7
2
3
1
0 100 400200 35030025015050
3.3V
IN
5V
IN
12V
IN
24V
IN
V
OUT
= 2.5V
