Datasheet

LT3980
3
3980fa
For more information www.linear.com/LT3980
PARAMETER CONDITIONS MIN TYP MAX UNITS
Quiescent Current from BD V
RUN/SS
= 0.2V
V
BD
= 3V, Not Switching
V
BD
= 0, Not Switching
55
0.01
82
1
0.5
115
5
µA
µA
µA
Feedback Voltage

●
782
770
790
790
798
805
mV
mV
FB Pin Bias Current (Note 3) V
FB
= 0.8V, V
C
= 1.2V
●
10 40 nA
FB Voltage Line Regulation 4V < V
IN
< 56V 0.002 0.01 %/V
Error Amp g
m
500 µmho
Error Amp Gain 1800
V
C
Source Current 60 µA
V
C
Sink Current 60 µA
V
C
Pin to Switch Current Gain 3.87 A/V
V
C
Clamp Voltage 2 V
Switching Frequency R
T
= 8.66k
R
T
= 29.4k
R
T
= 187k
1.95
0.86
195
2.25
1.07
225
2.55
1.27
255
MHz
MHz
kHz
Minimum Switch Off-Time
●
140 230 nS
Switch Current Limit Duty Cycle = 5% 3.3 4 4.9 A
Switch V
CESAT
I
SW
= 2A 540 mV
DA Pin Current to Pause OSC 1.9 2.4 3 A
Boost Schottky Reverse Leakage V
BD
= 0V 0.02 2 µA
Minimum Boost Voltage (Note 4)
●
1.7 2.2 V
BOOST Pin Current I
SW
= 2A 40 55 mA
RUN/SS Pin Current V
RUN/SS
= 2.5V 6 10 µA
RUN/SS Input Voltage High 2.5 V
RUN/SS Input Voltage Low
●
0.4 V
PG Threshold Offset from Feedback Voltage V
FB
Rising
●
50 65 80 mV
PG Hysteresis 14 mV
PG Leakage V
PG
= 5V 0.1 1 µA
PG Sink Current V
PG
= 0.4V
●
200 700 µA
SYNC Threshold 0.575 0.675 0.775 V
SYNC Pin Bias Current V
SYNC
= 0V 0.1 µA
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LT3980E is guaranteed to meet performance specifications
from 0°C to 125°C. Specifications over the –40°C to 125°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls. The LT3980I specifications are
guaranteed over the –40°C to 125°C temperature range. The LT3980H
specifications are guaranteed over the –40°C to 150°C operating
temperature range. High junction temperatures degrade operating
lifetimes. Operating lifetime is derated at junction temperatures greater
than 125°C.
Note 3: Bias current flows out of the FB pin.
Note 4: This is the minimum voltage across the boost capacitor needed to
guarantee full saturation of the switch.
Note 5: Absolute Maximum at V
IN
and RUN/SS pins is 80V for non-
repetitive 1 minute transients, and 60V for continuous operation.
The ● denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. V
IN
= 10V, V
RUN/SS
= 10V, V
BOOST
= 15V, V
BD
= 3.3V unless otherwise
noted. (Note 2)
elecTrical characTerisTics