LTC3890
elecTrical characTerisTics The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at TA = 25°C. VIN = 12V, VRUN1,2 = 5V, EXTVCC = 0V unless otherwise noted.
(Note 2)
SYMBOL
BG/TG t
PARAMETER
CONDITIONS
= 3300pF Each Driver
MIN
TYP
MAX
UNITS
Bottom Gate Off to Top Gate On Delay
Top Switch-On Delay Time
C
30
ns
1D
LOAD
t
Minimum On-Time
(Note 7)
95
ns
ON(MIN)
INTV Linear Regulator
CC
V
V
V
V
V
V
Internal V Voltage
6V < V < 60V, V = 0V
EXTVCC
4.85
4.85
4.5
5.1
0.7
5.1
0.6
4.7
250
5.35
1.1
V
%
V
INTVCCVIN
LDOVIN
CC
IN
INTV Load Regulation
I
CC
= 0mA to 50mA, V
= 0V
CC
EXTVCC
Internal V Voltage
6V < V < 13V
EXTVCC
5.35
1.1
INTVCCEXT
LDOEXT
CC
INTV Load Regulation
I
CC
= 0mA to 50mA, V
= 8.5V
%
V
CC
EXTVCC
EXTV Switchover Voltage
EXTV Ramping Positive
4.9
EXTVCC
CC
CC
EXTV Hysteresis
mV
LDOHYS
CC
Oscillator and Phase-Locked Loop
f
f
f
f
f
f
Programmable Frequency
Programmable Frequency
Programmable Frequency
Low Fixed Frequency
R
R
R
= 25k, PLLIN/MODE = DC Voltage
= 65k, PLLIN/MODE = DC Voltage
= 105k, PLLIN/MODE = DC Voltage
= 0V, PLLIN/MODE = DC Voltage
105
440
835
350
535
kHz
kHz
kHz
kHz
kHz
kHz
25kΩ
65kΩ
105kΩ
LOW
FREQ
FREQ
FREQ
FREQ
FREQ
375
505
V
V
320
485
75
380
585
850
High Fixed Frequency
= INTV , PLLIN/MODE = DC Voltage
CC
HIGH
SYNC
l
Synchronizable Frequency
PLLIN/MODE = External Clock
PGOOD1 and PGOOD2 Outputs
V
PGOOD Voltage Low
PGOOD Leakage Current
PGOOD Trip Level
I
= 2mA
= 5V
0.2
0.4
1
V
PGL
PGOOD
I
V
V
µA
PGOOD
PGOOD
V
PG
with Respect to Set Regulated Voltage
FB
V
Ramping Negative
–13
7
–10
2.5
–7
13
%
%
FB
Hysteresis
V
with Respect to Set Regulated Voltage
FB
V
Ramping Positive
10
2.5
%
%
FB
Hysteresis
t
PG
Delay for Reporting a Fault
25
µs
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Ratings for extended periods may affect device reliability and
lifetime.
Note 3: T is calculated from the ambient temperature T and power
J A
dissipation P according to the following formula:
D
T = T + (P • 34°C/W)
J
A
D
Note 4: The LTC3890 is tested in a feedback loop that servos V
to
ITH1,2
Note 2: The LTC3890 is tested under pulsed load conditions such that
a specified voltage and measures the resultant V . The specification at
FB
T ≈ T . The LTC3890E is guaranteed to meet performance specifications
J
A
85°C is not tested in production and is assured by design, characterization
and correlation to production testing at other temperatures (125°C for
the LTC3890E/LTC3890I, 150°C for the LTC3890H/LTC3890MP). For the
LTC3890MP, the specification at –40°C is not tested in production and is
assured by design, characterization and correlation to production testing
at –55°C.
from 0°C to 85°C. Specifications over the –40°C to 125°C operating
junction temperature range are assured by design, characterization and
correlation with statistical process controls. The LTC3890I is guaranteed
over the –40°C to 125°C operating junction temperature range, the
LTC3890H is guaranteed over the –40°C to 150°C operating junction
temperature range and the LTC3890MP is tested and guaranteed over the
–55°C to 150°C operating junction temperature range.
Note 5: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications information.
High junction temperatures degrade operating lifetimes; operating lifetime
is derated for junction temperatures greater than 125°C. Note that the
maximum ambient temperature consistent with these specifications is
determined by specific operating conditions in conjunction with board
layout, the rated package thermal impedance and other environmental
factors.
Note 6: Rise and fall times are measured using 10% and 90% levels. Delay
times are measured using 50% levels.
Note 7: The minimum on-time condition is specified for an inductor
peak-to-peak ripple current ≥ 40% of I
(See Minimum On-Time
MAX
Considerations in the Applications Information section).
3890fb
4
Linear Systems [ Linear Systems ]
