Datasheet LTC3731H (Analog Devices) - 4

LTC3731H e lecTrical characTerisTics
The
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denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = VRUN/SS = 5V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Power Good Output Indication
VPGL PGOOD Voltage Output Low IPGOOD = 2mA, G Package 0.1 0.3 V IPGOOD = 1.6mA, UH Package 0.5 1 V IPGOOD PGOOD Output Leakage VPGOOD = 5V 1 µA PGOOD Trip Thresholds VEAIN with Respect to Set Output Voltage, PGOOD VPGTHNEG VEAIN Ramping Negative Goes Low After VUVDLY Delay –7 –10 –13 % VPGTHPOS VEAIN Ramping Positive 7 10 13 % VPGDLY Power Good Fault Report Delay After VEAIN is Forced Outside the PGOOD Thresholds 100 150 µs
Oscillator and Phase-Locked Loop
fNOM Nominal Frequency VPLLFLTR = 1.2V 360 400 440 kHz fLOW Lowest Frequency VPLLFLTR = 0V 190 225 260 kHz fHIGH Highest Frequency VPLLFLTR = 2.4V 600 680 750 kHz VPLLTH PLLIN Input Threshold Minimum Pulse Width > 100ns 1 V RPLLIN PLLIN Input Resistance 50 kΩ IPLLFLTR Phase Detector Output Current Sinking Capability fPLLIN < fOSC 20 µA Sourcing Capability fPLLIN > fOSC 20 µA RRELPHS Controller 2-Controller 1 Phase 120 Deg Controller 3-Controller 1 Phase 240 Deg CLKOUT Controller 1 TG to CLKOUT Phase PHASMD = 0V 30 Deg PHASMD = 5V 60 Deg
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 3:
The IC is tested in a feedback loop that servoes the error amplifier may cause permanent damage to the device. Exposure to any Absolute output voltage to its midrange point (VITH = 1.2V). Maximum Rating condition for extended periods may affect device
Note 4:
Dynamic supply current is higher due to the gate charge being reliability and lifetime. delivered at the switching frequency. See Applications Information.
Note 2:
The LTC3731H is guaranteed to meet specifications over the –40°C
Note 5:
The minimum on-time condition corresponds to an inductor to 140°C operating junction temperature range. Note that the maximum peak-to-peak ripple current of ≥40% of IMAX (see minimum on-time ambient temperature is determined by specific operating conditions in considerations in the Applications Information Section). conjunction with board layout, the rated package thermal resistance and
Note 6:
This IC includes overtemperature protection that is intended other environmental factors. to protect the device during momentary overload conditions. Junction temperature (TJ) is calculated from the ambient temperature TA Overtemperature protection becomes active at a junction temperature and power dissipation PD according to the following formula: greater than the maximum operating temperature. Continuous operation LTC3731HG: TJ = TA + (PD • 70°C/W) above the specified maximum operating junction temperature may impair LTC3731HG: T device reliability. J = TCASE + (PD • 25°C/W) LTC3731HUH: TJ = TA + (PD • 34°C/W) High junction temperatures degrade operating lifetimes. Operating lifetime at junction temperatures greater than 125°C is derated to 1000 hours. The LTC3731H is tested under pulsed load conditions such that TJ ≈ TA. 3731Hfb Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts