LTC3371_15 Datasheet, PDF (5/26 Pages) Linear Technology – 4-Channel 8A Configurable Buck DC/DCs with Watchdog and Power-On Reset

LTC3371
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 2) V_CC = V_INA-H = 3.3V, unless otherwise specified.
SYMBOL
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Buck Regulators Combined
I_FWD2
PMOS Current Limit
2 Buck Power Stages Combined (Note 5)
4.6
A
I_FWD3
PMOS Current Limit
3 Buck Power Stages Combined (Note 5)
6.9
A
I_FWD4
PMOS Current Limit
4 Buck Power Stages Combined (Note 5)
9.2
A
Interface Logic Pins (RST1-4, WDO, WDI, PLL/MODE, C1, C2, C3)
I_OH
Output High Leakage Current
V_OL
Output Low Voltage
V_IH
WDI Input High Threshold
V_IL
WDI, C1, C2, C3 Input Low Threshold
t_WDI(WIDTH)
WDI Pulse Width
V_IH
PLL/MODE, C1, C2, C3 Input High Threshold
V_IL
PLL/MODE Input Low Threshold
Interface Logic Pins (EN1, EN2, EN3, EN4)
RST1-4, WDO 5.5V at Pin
RST1-4, WDO 3mA into Pin
1
µA
0.1
0.4
V
l 1.2
V
l
0.4
V
l 40
ns
l V_CC – 0.4
l
V
V_CC – 1.2
V
V_HI(ALLOFF)
Enable Rising Threshold
V_HI
Enable Rising Threshold
V_LO
Enable Falling Threshold
I_EN
Enable Pin Leakage Current
CT Timing Parameters; C_T = 10nF
t_WDI0
Time from WDO Low Until Next WDO Low
All Regulators Disabled
At Least One Regulator Enabled
EN = 3.3V
C_T = 10nF
l
730 1200
mV
l
400 420
mV
340 390
mV
1
µA
10.3 12.9 15.5
Sec
l 6.2 12.9
Sec
t_WDI
Time from Last WDI Until Next WDO Low
C_T = 10nF
1.30 1.62 1.95
Sec
l 0.77 1.62
Sec
t_WDL
Watchdog Lower Boundary
C_T = 10nF
40 50.6 60
ms
l
50.6 65
ms
t_WDO
WDO Low Time Absent a Transition at WDI
C_T = 10nF
t_RST
RST Assertion Delay
C_T = 10nF
160 202 280
ms
160 202 240
ms
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 LTC3371 is tested under pulsed load conditions such that
T_J ≈ T_A. The LTC3371E is guaranteed to meet 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
LTC3371I is guaranteed over the –40°C to 125°C operating junction
temperature range. The LTC3371H is guaranteed over the –40°C to 150°C
operating junction temperature 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 (in °C/W) is the package thermal impedance.
Note 3: The LTC3371 includes overtemperature protection which protects
the device during momentary overload conditions. Junction temperatures
will exceed 150°C when overtemperature protection is active. Continuous
operation above the specified maximum operating junction temperature
may impair device reliability.
Note 4: Static current, switches not switching. Actual current may be
higher due to gate charge losses at the switching frequency.
Note 5: The current limit features of this part are intended to protect the
IC from short term or intermittent fault conditions. Continuous operation
above the maximum specified pin current rating may result in device
degradation over time.
For more information www.linear.com/LTC3371
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