Datasheet LTC3372 (Analog Devices) - 7

LTC3372
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2), VIN = 12V, VRUN = 5V, VOUT = VINA-H = 3.3V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Interface Logic Pins (EN1, EN2, EN3, EN4)
VEN Enable Rising Threshold All LV Regulators Disabled l 400 730 1200 mV Enable Rising Threshold At Least One LV Regulator Enabled l 380 400 420 mV Enable Falling Threshold l 290 315 340 mV IEN Enable Pin Leakage Current EN = 3.3V 1 µA
CT Timing Parameters; CT = 10nF
tWDIO Time from WDO Low Until Next WDO Low CT = 10nF 9.7 12.9 16.1 s tWDI Time from Last WDI Until Next WDO Low CT = 10nF 1.22 1.62 2.03 s tWDO WDO Low Time Absent a Transition at WDI CT = 10nF 160 202 280 ms tRST RST Assertion Delay CT = 10nF 160 202 280 ms tWDL Watchdog Lower Boundary CT = 10nF 38 50.6 63 ms
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 4:
The IQ (Total Input Supply Quiescent Current) is the total average may cause permanent damage to the device. Exposure to any Absolute current drawn from the input power supply by a typical application in Burst Maximum Rating condition for extended periods may affect device Mode with no load currents (from either the HV Controller VOUT or the LV reliability and lifetime. Regulators’ VOUT1-4).
Note 2:
The LTC3372 is tested under pulsed load conditions such that
Note 5:
The HV Controller’s output regulation is tested in a feedback loop TJ ≈ TA. The LTC3372E is guaranteed to meet specifications from 0°C that servos the ITH pin to a specified voltage and measures the resulted to 85°C operating junction temperature. Specifications over the –40°C voltage at VOUT/EXTVCC pin. to 125°C operating junction temperature range are assured by design,
Note 6:
Delays are measured using 50% levels, with TG and BG driving characterization and correlation with statistical process controls. The minimum capacitive load. LTC3372I is guaranteed over the –40°C to 125°C operating junction
Note 7:
The minimum on-time conditions is specified for an inductor temperature range. The LTC3372H is guaranteed over the –40°C to 150°C peak-to-peak ripple current ≥40% of I operating junction temperature range. High junction temperatures degrade MAX (see Minimum On-Time Considerations in the Applications Information section). operating lifetimes; operating lifetime is derated for junction temperatures greater than 125°C. Note that the maximum ambient temperature
Note 8:
The IQ(VINA-H) (Quiescent Current into VINA-H Pins) are measured consistent with these specifications is determined by specific operating with power switches not switching. Dynamic supply current when conditions in conjunction with board layout, the rated package thermal switching may be higher due to the gate charge being delivered. impedance and other environmental factors. The junction temperature (T
Note 9:
The current limit features are intended to protect the IC from short J in °C) is calculated from the ambient temperature (T term or intermittent fault conditions. Continuous operation above the A in °C) and power dissipation (P maximum specified pin current rating may result in device degradation D in Watts) according to the formula: T over time. J = TA + (PD • θJA) where
Note 10:
The soft-start is the time from the first top switch turn on, θJA (in °C/W) is the package thermal impedance. after an enable rising, until the feedback has reached 90% of its nominal
Note 3:
This IC includes overtemperature protection which protects the regulation voltage. device during momentary overload conditions. Junction temperatures will exceed 150°C when overtemperature protection is active. Continuous
Note 11:
Do not apply a voltage or current source to these pins. They operation above the specified maximum operating junction temperature must be connected to the gates of the external power MOSFETs, otherwise may impair device reliability. permanent damage may occur. Rev. A For more information www.analog.com 7 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Low Voltage Regulators Applications Information High Voltage Buck Controller Low Voltage Buck Regulators Printed Circuit Board PCB Layout Considerations Typical Applications Package Description Revision History Typical Application Related Parts