LTC1778 Linear Technology, LTC1778 Datasheet - Page 2

• Manufacturer Part Number: LTC1778
• Description: Wide Operating Range/ No RSENSE Step-Down Controller
• Manufacturer: Linear Technology

ABSOLUTE AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
ELECTRICAL CHARACTERISTICS
LTC1778/LTC1778-1
Input Supply Voltage (V
Boosted Topside Driver Supply Voltage
(BOOST) ................................................... 42V to – 0.3V
SW Voltage .................................................. 36V to – 5V
EXTV
FCB, V
I
Consult LTC Marketing for parts specified with wider operating temperature ranges.
temperature range, otherwise specifications are T
SYMBOL
Main Control Loop
I
V
I
g
V
I
t
t
2
PGOOD Voltages ....................................... 7V to – 0.3V
TH
Q
FB
FCB
ON
ON(MIN)
m(EA)
FB
FCB
V
V
FB(LINEREG)
FB(LOADREG)
, V
RUN/SS
PGOOD
CC
FB
SGND
V
ON
RNG
FCB
V
I
I
, (BOOST – SW), RUN/SS,
ON
TH
FB
Voltages...................................... 2.7V to – 0.3V
T
, V
JMAX
16-LEAD PLASTIC SSOP
1
2
3
4
5
6
7
8
RNG
= 125 C,
PARAMETER
Input DC Supply Current
Feedback Reference Voltage
Feedback Voltage Line Regulation
Feedback Voltage Load Regulation
Feedback Input Current
Error Amplifier Transconductance
Forced Continuous Threshold
Forced Continuous Pin Current
On-Time
Minimum On-Time
GN PACKAGE
Normal
Shutdown Supply Current
TOP VIEW
Voltages .......... INTV
W
JA
= 130 C/ W
16
15
14
13
12
11
10
9
IN
, I
BOOST
TG
SW
PGND
BG
INTV
V
EXTV
W W
IN
ON
CC
CC
)................. 36V to – 0.3V
U
GN PART MARKING
CC
ORDER PART
+ 0.3V to – 0.3V
LTC1778EGN
W
NUMBER
A
U
1778
= 25 C. V
CONDITIONS
I
V
I
V
I
V
I
I
I
TH
TH
TH
ON
ON
ON
IN
FB
FCB
= 1.2V (Note 3)
= 0.5V to 1.9V (Note 3)
= 1.2V (Note 3)
= 4V to 30V, I
= 30 A, V
= 15 A, V
= 180 A
= 0.8V
The
= 0.8V
U
(Note 1)
IN
= 15V unless otherwise noted.
denotes specifications which apply over the full operating
ON
ON
= 0V (LTC1778-1)
= 0V (LTC1778-1)
TG, BG, INTV
TG, BG, INTV
Operating Ambient Temperature
Junction Temperature (Note 2) ............................ 125 C
Storage Temperature Range ................. – 65 C to 150 C
Lead Temperature (Soldering, 10 sec).................. 300 C
TH
= 1.2V (Note 3)
Range (Note 4) ................................... – 40 C to 85 C
RUN/SS
SGND
V
V
RNG
FCB
V
I
I
ON
ON
TH
FB
T
JMAX
16-LEAD PLASTIC SSOP
1
2
3
4
5
6
7
8
= 125 C,
GN PACKAGE
TOP VIEW
CC
CC
, EXTV
, EXTV
JA
= 130 C/ W
16
15
14
13
12
11
10
9
CC
CC
BOOST
TG
SW
PGND
BG
INTV
V
EXTV
Peak Currents .................... 2A
RMS Currents .............. 50mA
IN
CC
0.792
CC
0.76
MIN
198
396
1.4
GN PART MARKING
– 0.05
0.800
0.002
TYP
900
233
466
1.7
0.8
15
–5
– 1
50
LTC1778EGN-1
ORDER PART
NUMBER
17781
0.808
MAX
2000
– 0.3
0.84
268
536
100
30
– 2
2
50
UNITS
1778fa
%/V
mS
nA
ns
ns
ns
%
A
A
V
V
A