LTC3829
5
3829fc
For more information www.linear.com/LTC3829
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Nonlinear Fast Transit Mode
I
FAST
Fast Transient Programmable Current V
IFAST
= 400mV 9 10 11 µA
AVP (Active Voltage Positioning)
I
SINK
Sink Current of AVP Pin SENSE
+
= 1.2V 250 µA
I
SOURCE
Source Current of AVP Pin SENSE
+
= 1.2V 2 mA
V
AVP
-V
O(MAX)
Maximum Voltage Drop V
AVP
to V
O
SENSE
+
= 1.2V 180 mV
V
AVP
Maximum AVP Voltage
l
2.5 V
On-Chip Driver
TG R
UP
TG Pull-Up R
DS(ON)
TG High 2.6 Ω
TG R
DOWN
TG Pull-Down R
DS(ON)
TG Low 1.5 Ω
BG R
UP
BG Pull-Up R
DS(ON)
BG High 4 Ω
BG R
DOWN
BG Pull-Down R
DS(ON)
BG Low 1.1 Ω
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
IN
= 15V, V
RUN
= 5V, unless otherwise noted. (Note 2)
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 LTC3829 is tested under pulsed load conditions such that
T
J
≈ T
A
. The LTC3829E is guaranteed to meet performance specifications
from 0°C to 85°C operating junction temperature. Specifications over
the –40°C to 125°C operating junction temperature range are assured by
design, characterization and correlation with statistical process controls.
The LTC3829I is guaranteed to meet per
formance specifications over the
full –40°C to 125°C operating junction temperature range.
Note 3: T
J
is calculated from the ambient temperature, T
A
, and power
dissipation, P
D
, according to the following formula:
LTC3829UHF: T
J
= T
A
+ (P
D
• 34°C/W)
LTC3829FE: T
J
= T
A
+ (P
D
• 25°C/W)
Note 4: The LTC3829 is tested in a feedback loop that servos V
ITH
to a
specified voltage and measures the resultant V
FB
.
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 corresponds to the on inductor
peak-to-peak ripple current ≥40% of I
MAX
(see Minimum On-Time
Considerations in the Applications Information section).
Note 8: Guaranteed by design.
TYPICAL PERFORMANCE CHARACTERISTICS
Load Step-Up (0A to 75A, 75A/µs)
(Nonlinear Operation)
Load Step-Up (0A to 75A, 75A/µs)
(Normal Operation)
V
OUT
100mV/DIV
AC-COUPLED
V
SW1
10V/DIV
V
SW2
10V/DIV
V
SW3
10V/DIV
2µs/DIV
3829 G01
75mV
V
OUT
100mV/DIV
AC-COUPLED
V
SW1
10V/DIV
V
SW2
10V/DIV
V
SW3
10V/DIV
2µs/DIV
3829 G02
95mV
