Datasheet LTC3874 (Analog Devices) - 4

LTC3874
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, VRUN0,1 = 3.3V unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Oscillator and Phase-Locked Loop
fRANGE PLL SYNC Range l 250 1000 kHz fNOM Nominal Frequency VFREQ = 0.9V 500 kHz IFREQ Frequency Setting Current 9 10 11 µA θ SYNC-θ0 SYNC to Ch0 Phase Relationship Based on PHASMD = 0 180 Deg the Falling Edge of SYNC and Rising Edge PHASMD = 1/3 • INTVCC 60 Deg of TG0 PHASMD = 2/3 • INTVCC 120 Deg PHASMD = INTVCC 90 Deg θ SYNC-θ1 SYNC to Ch1 Phase Relationship Based on PHASMD = 0 0 Deg the Falling Edge of SYNC and Rising Edge PHASMD = 1/3 • INTVCC 300 Deg of TG1 PHASMD = 2/3 • INTVCC 240 Deg PHASMD = INTVCC 270 Deg
Digital Inputs RUN0, RUN1, MODE0, MODE1, FAULT0, FAULT1, LOWDCR
VIH Input High Threshold Voltage l 2.0 V VIL Input Low Threshold Voltage l 1.4 V
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 3:
Output voltage is set and controlled by master controller in may cause permanent damage to the device. Exposure to any Absolute multiphase operations. 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 Application Information.
Note 2:
The LTC3874 is tested under pulsed load conditions such that
Note 5:
Rise and fall times are measured using 10% and 90% levels. Delay TJ ≈ TA. The LTC3874E is guaranteed to meet performance specifications times are measured using 50% levels. from 0°C to 85°C. Specifications over the –40°C to 125°C operating
Note 6:
The minimum on-time condition corresponds to an inductor junction temperature range are assured by design, characterization and peak-to-peak ripple current ≥ 40% of IMAX (see Minimum On-Time correlation with statistical process controls. The LTC3874I is guaranteed Considerations in the Applications Information section). over the –40°C to 125°C operating junction temperature range. High
Note 7:
EXTV junction temperatures degrade operating lifetimes; operating lifetime CC is enabled only if VIN is higher than 7V. 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. TJ is calculated from the ambient temperature TA and power dissipation PD according to the following formula: TJ = TA + (PD • 43˚C/W) 3874fb 4 For more information www.linear.com/LTC3874 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Operation Applications Information Package Description Typical Application Related Parts Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Block Diagram Operation Applications Information Package Description Revision History Typical Application Related Parts