LTC3124_15 Datasheet, PDF (3/28 Pages) Linear Technology – 15V, 5A 2-Phase Synchronous Step-Up DC/DC Converter with Output Disconnect

LTC3124
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the specified operating
junction temperature range, otherwise specifications are at T_A = 25°C (Note 3). V_IN = 3.6V, V_OUTA = V_OUTB = 12V, R_T = 28k unless
otherwise noted.
PARAMETER
CONDITIONS
MIN
TYP
MAX UNITS
Minimum Start-Up Voltage
Input Voltage Range
Output Voltage Adjust Range
V_OUT = 0V
V_OUT ≥ 2.5V
l
1.6
1.8
V
l 0.5
5.5
V
l 2.5
15
V
Feedback Voltage
l 1.176 1.200 1.224
V
Feedback Input Current
FB = 1.4V
1
50
nA
Quiescent Current, Shutdown
SD = 0V, V_OUT = 0V, Not Including Switch Leakage
Quiescent Current, Active
FB = 1.4V, Measured on V_IN, Non-Switching
Quiescent Current, Burst
Measured on V_IN, FB = 1.4V
Measured on V_OUT, FB = 1.4V
N-Channel MOSFET Switch Leakage Current SW = 15V, V_OUT = 15V, Per Phase
l
P-Channel MOSFET Switch Leakage Current SW = 0V, V_OUT = 15V, SD = 0V, Per Phase
l
N-Channel MOSFET Switch On-Resistance Per Phase
0.2
1
µA
600
840
µA
25
40
µA
10
20
µA
0.1
40
µA
0.1
70
µA
0.130
Ω
P-Channel MOSFET Switch On-Resistance Per Phase
0.200
Ω
N-Channel MOSFET Peak Current Limit
Per Phase
l 2.5
3.5
4.5
A
Maximum Duty Cycle
FB = 1.0V
l 90
94
%
Minimum Duty Cycle
FB = 1.4V
l
0
%
Switching Frequency
Per Phase
l 0.83
1
1.17
MHz
SYNC Frequency Range
l 0.2
6.0
MHz
PWM/SYNC Input High Voltage
PWM/SYNC Input Low Voltage
PWM/SYNC Input Current
CAP Clamp Voltage
V_CC Regulation Voltage
Error Amplifier Transconductance
V_PWM/SYNC = 5.5V
V_OUT > 6.2V, Referenced to V_OUT
V_IN < 2.8V, V_OUT > 5V
l 0.9 • V_CC
V
l
0.1 • V_CC
V
0.01
1
µA
–5.0
–5.4
–5.8
V
3.9
4.25
4.6
V
l 60
100
130
µS
Error Amplifier Sink Current
FB = 1.6V, VC = 1.15V
25
µA
Error Amplifier Source Current
FB = 800mV, VC = 1.15V
–25
µA
Soft-Start Time
10
ms
SD Input High Voltage
l 1.6
V
SD Input Low Voltage
l
0.25
V
SD Input Current
SD = 5.5V
1
2
µA
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: Voltage transients on the SW pin beyond the DC limit specified in
the Absolute Maximum Ratings are non-disruptive to normal operations
when using good layout practices, as shown on the demo board or
described in the data sheet or application notes.
Note 3: The LTC3124 is tested under pulsed load conditions such that
T_A ≈ T_J. The LTC3124E is guaranteed to meet performance specifications
from 0°C to 85°C 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
LTC3124I is guaranteed to meet specifications over the –40°C to 125°C
operating junction temperature range. The LTC3124H is guaranteed to
meet specifications over the full –40°C to 150°C operating junction range.
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. The junction temperature (T_J in °C) is
calculated from the ambient temperature (T_A in °C) and power dissipation
(P_D in Watts) according to the formula:
T_J = T_A + (P_D • θ_JA)
where θ_JA is the thermal impedance of the package.
Note 4: The LTC3124 includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperature will exceed 150°C when overtemperature shutdown is active.
Continuous operation above the specified maximum operating junction
temperature may result in device degradation or failure.
Note 5: Failure to solder the exposed backside of the package to the PC
board ground plane will result in a thermal impedance much higher than
the rated package specifications.
3124f
For more information www.linear.com/LTC3124
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