LT1977
ABSOLUTE
(Note 1)
AXI U RATI GS
PACKAGE/ORDER I FOR ATIO
TOP VIEW
NC
SW
NC
V
IN
NC
BOOST
C
T
GND
1
2
3
4
5
6
7
8
17
16 PG
15 SHDN
14 SYNC
13 PGFB
12 FB
11 V
C
10 BIAS
9
C
SS
V
IN
, SHDN, BIAS ..................................................... 60V
BOOST Pin Above SW ............................................ 35V
BOOST Pin Voltage ................................................. 68V
SYNC, C
SS
, PGFB, FB ................................................ 6V
Operating JunctionTemperature Range
LT1977EFE (Note 2) ........................ – 40°C to 125°C
LT1977IFE (Note 2) ......................... – 40°C to 125°C
Storage Temperature Range ................. – 65°C to 150°C
Lead Temperature (Soldering, 10 sec).................. 300°C
ORDER PART
NUMBER
LT1977EFE
LT1977IFE
FE PART
MARKING
1977EFE
1977IFE
FE PACKAGE
16-LEAD PLASTIC TSSOP
T
JMAX
= 125°C,
θ
JA
= 45°C/W,
θ
JC(PAD)
= 10°C/W
EXPOSED PAD IS GND (PIN 17)
MUST BE SOLDERED TO GND (PIN 8)
Consult LTC Marketing for parts specified with wider operating temperature ranges.
The
●
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
J
= 25°C. V
IN
= 12V, SHDN = 12V, BIAS = 5V, FB/PGFB = 1.25V, C
SS
/SYNC = 0V
unless otherwise noted.
SYMBOL
V
SHDN
I
SHDN
I
VINS
PARAMETER
SHDN Threshold
SHDN Input Current
Minimum Input Voltage (Note 3)
Supply Shutdown Current
Supply Sleep Current (Note 4)
I
VIN
Supply Quiescent Current
Minimum BIAS Voltage (Note 5)
I
BIASS
I
BIAS
BIAS Sleep Current (Note 4)
BIAS Quiescent Current
Minimum Boost Voltage (Note 6)
Input Boost Current (Note 7)
V
REF
I
FB
Reference Voltage (V
REF
)
FB Input Bias Current
EA Voltage Gain (Note 8)
EA Voltage g
m
EA Source Current
EA Sink Current
V
C
to SW g
m
V
C
High Clamp
I
PK
SW Current Limit
●
ELECTRICAL CHARACTERISTICS
CONDITIONS
SHDN = 12V
SHDN = 0V, BOOST = 0V, FB/PGFB = 0V
BIAS = 0V, FB = 1.35V
FB = 1.35V
BIAS = 0V, FB = 1.15V
BIAS = 5V, FB = 1.15V
●
●
●
●
●
●
MIN
1.15
TYP
1.3
5
2.4
0.1
170
45
MAX
1.45
20
3
2
250
75
4.10
3.25
UNITS
V
µA
V
µA
µA
µA
mA
mA
V
µA
µA
V
mA
2.7
110
700
1.8
40
3
180
900
SYNC = 3.3V
I
SW
= 1.5A
I
SW
= 1.5A
3.3V < V
VIN
< 60V
●
1.225
1.25
75
900
1.275
200
900
55
40
2.4
3.5
dI(V
C
)=
±10µA
FB = 1.15V
FB = 1.35V
450
20
15
2.1
1.5
650
40
30
3
2.2
2.4
µMho
µA
µA
A/V
V
A
2
U
V
nA
V/V
1977f
W
U
U
W W
W
LINER [ LINEAR TECHNOLOGY ]
