LTC3827
4
3827ff
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 LTC3827E is guaranteed to meet performance specifi cations
from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls. The LTC3827I is guaranteed to meet
performance specifi cations over the full –40°C to 85°C operating
temperature range.
Note 3: T
J
is calculated from the ambient temperature T
A
and power
dissipation P
D
according to the following formulas:
T
J
= T
A
+ (P
D
• 34 °C/W)
Note 4: The LTC3827 is tested in a feedback loop that servos V
ITH1, 2
to a
specifi ed voltage and measures the resultant V
FB1, 2.
Note 5: Dynamic supply current is higher due to the gate charge being
delivered at the switching frequency. See Applications Information.
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 specifi ed for an inductor
peak-to-peak ripple current ≥40% of I
MAX
(see minimum on-time
considerations in the Applications Information section).
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
f
SYNCMAX
Maximum Synchronizable Frequency PLLIN/MODE = External Clock; V
PLLLPF
= 2V 650 800 kHz
I
PLLLPF
Phase Detector Output Current
Sinking Capability
Sourcing Capability
f
PLLIN/MODE
< f
OSC
f
PLLIN/MODE
> f
OSC
–5
5
µA
µA
PGOOD Output
V
PGL
PGOOD Voltage Low I
PGOOD
= 2mA 0.1 0.3 V
I
PGOOD
PGOOD Leakage Current V
PGOOD
= 5V ±1 µA
V
PG
PGOOD Trip Level V
FB
with Respect to Set Regulated Voltage
V
FB
Ramping Negative
V
FB
Ramping Positive
–12
8
–10
10
–8
12
%
%
ELECTRICAL CHARACTERISTICS
The l denotes the specifi cations which apply over the full operating
temperature range, otherwise specifi cations are at T
A
= 25°C. V
IN
= 12V, V
RUN/SS1, 2
= 5V unless otherwise noted.
