Datasheet

LTM4618
3
4618fa
ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full internal
operating temperature range, otherwise specifi cations are at T
A
= 25°C (Note 2), V
IN
= 12V, per typical application in Figure 21.
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
I
Q(VIN)
Input Supply Bias Current V
IN
= 12V, V
OUT
= 2.5V, I
OUT
= 0A
V
IN
= 26.5V, V
OUT
= 2.5V, I
OUT
= 0A
Shutdown, RUN = 0, V
IN
= 26.5V
26
20
80
mA
mA
µA
I
S(VIN)
Input Supply Current V
IN
= 12V, V
OUT
= 2.5V, I
OUT
= 6A
V
IN
= 26.5V, V
OUT
= 2.5V, I
OUT
= 6A
1.430
0.675
A
A
INTV
CC
Internal V
CC
Voltage V
IN
= 12V, V
RUN
> 2V, No Load 4.8 5 5.2 V
V
EXTVCC
EXTV
CC
Switchover Voltage EXTV
CC
Ramping Positive
l
4.5 4.7 V
VLDO External EXTV
CC
Voltage Drop INTV
CC
= 20mA, V
EXTVCC
= 5V 50 100 mV
V
EXTVCC
Hysteresis EXTV
CC
Hysteresis 200 mV
Output Specifi cations
I
OUT(DC)
Output Continuous Current Range V
IN
= 12V, V
OUT
= 2.5V (Note 4) 0 6 A
ΔV
OUT(LINE)
V
OUT
Line Regulation Accuracy V
OUT
= 2.5V, V
IN
from 6V to 26.5V
I
OUT
= 0A
l
0.02 0.04 %/V
ΔV
OUT(LOAD)
V
OUT
Load Regulation Accuracy V
IN
= 12V, V
OUT
= 2.5V, 0 to 6A (Note 4)
l
0.3 0.6 %
V
OUT(AC)
Output Ripple Voltage I
OUT
= 0A, C
OUT
= 100µF ×3 X5R Ceramic
V
IN
= 12V, V
OUT
= 2.5V
V
IN
= 26.5V, V
OUT
= 2.5V
10
12
mV
mV
f
S
Output Ripple Voltage Frequency I
OUT
= 2A, V
IN
= 12V, V
OUT
= 2.5V, V
FREQ
= INTV
CC
780 kHz
ΔV
OUT(START)
Turn-On Overshoot C
OUT
= 100µF ×3 X5R Ceramic
V
OUT
= 2.5V, I
OUT
= 0A
V
IN
= 12V
V
IN
= 26.5V
20
20
mV
mV
t
START
Turn-On Time C
OUT
= 100µF ×3 X5R Ceramic,
V
OUT
= 2.5V, I
OUT
= 0A, TK/SS Capacitor = 0.01µF
V
IN
= 12V
V
IN
= 26.5V
0.75
0.70
ms
ms
ΔV
OUTLS
Peak Deviation for Dynamic Load Load: 0% to 50% of Full Load
C
OUT
= 100µF ×3 X5R Ceramic, V
OUT
= 2.5V
V
IN
= 12V 15 mV
t
SETTLE
Settling Time for Dynamic Load Step Load: 0% to 50% of Full Load
C
OUT
= 100µF ×3 X5R Ceramic, V
OUT
= 2.5V
V
IN
= 12V 10 µs
I
OUT(PK)
Output Current Limit C
OUT
= 100µF ×3 X5R Ceramic
V
IN
= 6V, V
OUT
= 2.5V
V
IN
= 26.5V, V
OUT
= 2.5V
11
11
A
A
Control Section
V
FB
Error Amplifi er Feedback Voltage I
OUT
= 0A, V
OUT
= 2.5V
l
0.792
0.788
0.8
0.8
0.808
0.808
V
V
I
FB
Error Amplifi er Feedback Current (Note 3) –10 –50 nA
V
OVL
Feedback Voltage Lockout Measured at V
FB
0.84 0.86 0.88 V
I
TK/SS
Soft-Start Charge Current V
TK/SS
= 0V 0.9 1.3 1.7 µA
DF
MAX
Maximum Duty Factor In Dropout (Note 3) 97 %
t
ON(MIN)
Minimum On-Time (Note 3) 90 ns
f
NOM
Nominal Frequency V
FREQ
= 1.2V 450 500 550 kHz
f
LOW
Lowest Frequency V
FREQ
= 0V 210 250 290 kHz