Datasheet

LTC3786
3
3786fc
For more information www.linear.com/LTC3786
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are at T
A
= 25°C. V
BIAS
= 12V, unless otherwise noted (Note 2).
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Main Control Loop
VBIAS Chip Bias Voltage Operating Range 4.5 38 V
V
FB
Regulated Feedback Voltage I
TH
= 1.2V (Note 4)
l
1.188 1.200 1.212 V
I
FB
Feedback Current (Note 4) ±5 ±50 nA
V
REFLNREG
Reference Line Voltage Regulation V
BIAS
= 6V to 38V 0.002 0.02 %/V
V
LOADREG
Output Voltage Load Regulation (Note 4)
Measured in Servo Loop;
∆I
TH
Voltage = 1.2V to 0.7V
Measured in Servo Loop;
∆I
TH
Voltage = 1.2V to 2V
l
l
0.01
–0.01
0.1
–0.1
%
%
g
m
Error Amplifier Transconductance I
TH
= 1.2V 2 mmho
I
Q
Input DC Supply Current
Pulse-Skipping or Forced Continuous Mode
Sleep Mode
Shutdown
(Note 5)
RUN = 5V; V
FB
= 1.25V (No Load)
RUN = 5V; V
FB
= 1.25V (No Load)
RUN = 0V
0.8
55
8
80
20
mA
µA
µA
UVLO INTV
CC
Undervoltage Lockout Thresholds V
INTVCC
Ramping Up
V
INTVCC
Ramping Down
l
l
3.6
4.1
3.8
4.3 V
V
V
RUN
RUN Pin On Threshold V
RUN
Rising
l
1.18 1.28 1.38 V
V
RUNHYS
RUN Pin Hysteresis 100 mV
I
RUNHYS
RUN Pin Hysteresis Current V
RUN
> 1.28V 4.5 µA
I
RUN
RUN Pin Current V
RUN
< 1.28V 0.5 µA
I
SS
Soft-Start Charge Current V
SS
= 0V 7 10 13 µA
V
SENSE(MAX)
Maximum Current Sense Threshold V
FB
= 1.1V
l
68 75 82 mV
V
SENSE(CM)
SENSE Pins Common Mode Range (BOOST
Converter Input Supply Voltage V
IN
)
2.5 38 V
I
SENSE
+
SENSE
+
Pin Current V
FB
= 1.1V 200 300 µA
I
SENSE
–
SENSE
–
Pin Current V
FB
= 1.1V ±1 µA
t
r(TG)
Top Gate Rise Time C
LOAD
= 3300pF (Note 6) 20 ns
t
f(TG)
Top Gate Fall Time C
LOAD
= 3300pF (Note 6) 20 ns
t
r(BG)
Bottom Gate Rise Time C
LOAD
= 3300pF (Note 6) 20 ns
t
f(BG)
Bottom Gate Fall Time C
LOAD
= 3300pF (Note 6) 20 ns
R
UP(TG)
Top Gate Pull-Up Resistance 1.2 Ω
R
DN(TG)
Top Gate Pull-Down Resistance 1.2 Ω
R
UP(BG)
Bottom Gate Pull-Up Resistance 1.2 Ω
R
DN(BG)
Bottom Gate Pull-Down Resistance 1.2 Ω
t
D(TG/BG)
Top Gate Off to Bottom Gate On Switch-On
Delay Time
C
LOAD
= 3300pF (Each Driver) 80 ns
t
D(BG/TG)
Bottom Gate Off to Top Gate On Switch-On
Delay Time
C
LOAD
= 3300pF (Each Driver) 80 ns
DF
MAXBG
Maximum BG Duty Factor 96 %
t
ON(MIN)
Minimum BG On-Time (Note 7) 110 ns
Downloaded from Arrow.com.Downloaded from Arrow.com.Downloaded from Arrow.com.