LTC3425_15 Datasheet, PDF (3/24 Pages) Linear Technology – 5A, 8MHz, 4-Phase Synchronous Step-Up DC/DC Converter

LTC3425
ELECTRICAL CHARACTERISTICS The q denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T_A = 25°C. V_IN = 1.2V, V_OUT = 3.3V, R_T = 15k, unless otherwise noted.
PARAMETER
PMOS Turn-Off Current
PMOS Reverse Current Limit
Max Duty Cycle
Min Duty Cycle
Frequency Accuracy
SHDN Input High
SHDN Input Low
SHDN Input Current
REFEN, CCM Input High
REFEN, CCM Input Low
REFEN, Input Current
SYNCIN Input High
SYNCIN Input Low
SYNCIN Input Current
CCM Input Current
SYNC Input Pulse Width Range
SYNC Out High
SYNC Out Low
REFOUT
Error Amp Transconductance
Error Amp Output High
Error Amp Output Low
PGOOD Threshold (Falling Edge)
PGOOD Hysteresis
PGOOD Low Voltage
PGOOD Leakage
SS Current Source
Burst Threshold Voltage
Burst Threshold Hysteresis
CONDITIONS
CCM < 0.4V
CCM > 1.4V
R_T = 15k
V_OUT = 0V (Initial Start-Up)
V_OUT > 2.4V
V_SHDN = 5V or 0V
V_SHDN = 2V
V_REFEN = 5V
(Note 7)
(Note 7)
V_SYNCIN = 5V
V_CCM = 5V
REFEN > 1.4V, No Load
I_SOURCE < 100µA, I_SINK < 10µA
I_LIM Resistor = 75k
Referenced to Feedback Voltage
Referenced to Feedback Voltage
I_SINK = 1mA (10mA Max)
V_PGOOD = 5.5V
V_SS = 1V
Falling Edge
MIN
q 83
q
q 0.8
q1
q 0.65
q
q 1.4
q
q 2.5
q
q 0.1
3
q 1.190
q 1.184
q –9.5
q 1.5
q
q
q 0.84
TYP
– 80
0.6
90
1
0.01
–0.50
0.01
0.3
2
1.220
1.220
50
2.2
0.15
–11.4
2.5
0.12
0.01
2.7
0.94
120
MAX
97
0
1.2
0.25
1
0.4
1
0.5
1
4
0.4
1.251
1.252
–13.5
4
0.25
1
1.04
UNITS
mA
A
%
%
MHz
V
V
V
µA
µA
V
V
µA
V
V
µA
µA
µs
V
V
V
V
µS
V
V
%
%
V
µA
µA
V
mV
Note 1: Absolute Maximum Ratings are those values beyond which the life
of a device may be impaired.
Note 2: Current is measured into the V_OUTS pin since the supply current is
bootstrapped to the output. The current will reflect to the input supply by
V_OUT/(V_IN • Efficiency). The outputs are not switching.
Note 3: Once the output is started, the IC is not dependent on the V_IN
supply.
Note 4: Total with all four FETs in parallel.
Note 5: The LTC3425E is guaranteed to meet performance specifications
from 0°C to 70°C. Specifications over the –40°C to 85°C operating
temperature range are assured by design, characterization and correlation
with statistical process controls.
Note 6: This IC includes overtemperature protection that is intended to
protect the device during momentary overload conditions. Junction
temperature will exceed 125°C when overtemperature protection is active.
Continuous operation above the specified maximum operating junction
temperature may impair device reliability.
Note 7: The typical logic threshold for this input is: V_OUT/2
3425f
3