LTC3788 Linear Technology, LTC3788 Datasheet - Page 4

• Manufacturer Part Number: LTC3788
• Description: Dual Output Synchronous Boost Controller
• Manufacturer: Linear Technology

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LTC3788
ELECTRICAL CHARACTERISTICS
SYMBOL
DF
t
INTV
V
V
V
V
V
V
Oscillator and Phase-Locked Loop
f
f
f
f
PGOOD1 and PGOOD2 Outputs
V
I
V
t
BOOST1 and BOOST2 Charge Pump
I
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 LTC3788E is guaranteed to meet specifi cations from 0°C
to 85°C. Specifi cations over the –40°C to 125°C operating junction
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTC3788I is guaranteed over the full
–40°C to 125°C operating junction temperature range.
Note 3: T
dissipation P
4
junction temperature range, otherwise specifi cations are at T
ON(MIN)
PROG
LOW
HIGH
SYNC
PGOOD
PGOOD(DELAY)
BOOST1,2
INTVCCVIN
LDOVIN
INTVCCEXT
LDOEXT
EXTVCC
LDOHYS
PGL
PG
MAX(BG1,2)
CC
Linear Regulator
J
is calculated from the ambient temperature T
D
according to the formula: T
PARAMETER
Maximum BG Duty Factor
Minimum BG On-Time
Internal V
INTV
Internal V
INTV
EXTV
EXTV
Programmable Frequency
Lowest Fixed Frequency
Highest Fixed Frequency
Synchronizable Frequency
PGOOD Voltage Low
PGOOD Leakage Current
PGOOD Trip Level
PGOOD Delay
BOOST Charge Pump Available
Output Current
CC
CC
CC
CC
Load Regulation
Load Regulation
Switchover Voltage
Hysteresis
CC
CC
Voltage
Voltage
J
= T
A
+ (P
D
• 34°C/W)
A
and power
CONDITIONS
(Note 7)
6V < VBIAS < 38V, V
I
V
I
EXTV
R
R
R
V
V
PLLIN/MODE = External Clock
I
V
V
V
Hysteresis
V
Hysteresis
PGOOD Going High to Low
V
FREQ = 0V, Forced Continuous or
Pulse-Skipping Mode
CC
CC
PGOOD
EXTVCC
FREQ
FREQ
PGOOD
FB
FB
FB
SW1,2
FREQ
FREQ
FREQ
= 0mA to 50mA, V
= 0mA to 40mA, V
The
with Respect to Set Regulated Voltage
Ramping Negative
Ramping Positive
CC
A
= 25k
= 60k
= 100k
= 0V
= INTV
= 2mA
= 12V; V
Ramping Positive
= 5V
= 25°C, VBIAS = 12V, unless otherwise noted (Note 2).
= 6V
l
denotes the specifi cations which apply over the full operating
CC
BOOST1,2
Note 4: The LTC3788 is tested in a feedback loop that servos V
output of the error amplifi er while maintaining I
current limit range.
Note 5: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency.
Note 6: Rise and fall times are measured using 10% and 90% levels.
Delay times are measured using 50% levels.
Note 7: See Minimum On-Time Considerations in the Applications
Information section.
EXTVCC
EXTVCC
EXTVCC
– V
= 0V
SW1,2
= 0V
= 6V
= 4.5V;
l
MIN
335
320
485
–12
5.2
5.2
4.5
75
8
TYP
TH
110
250
105
400
760
350
535
–10
5.4
0.5
5.4
0.5
4.8
0.2
2.5
2.5
96
10
25
55
at the midpoint of the
MAX
465
380
585
850
5.6
5.6
0.4
±1
–8
12
2
2
5
FB
to the
UNITS
3788f
kHz
kHz
kHz
kHz
kHz
kHz
mV
μA
μA
ns
μs
%
%
%
%
%
%
%
V
V
V
V