Datasheet LTC3896 (Analog Devices) - 5

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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), VIN = 12V, VRUN = 5V with respect to VOUT , EXTVCC = 0V, V – DRVSET = 0V, VPRG = FLOAT unless otherwise noted. All pin voltages with respect to VOUT , unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Low Fixed Frequency V – FREQ = VOUT , PLLIN = DC Voltage 320 350 380 kHz High Fixed Frequency VFREQ = INTVCC, PLLIN = DC Voltage 485 535 585 kHz fSYNC Synchronizable Frequency PLLIN = External Clock l 75 850 kHz PLLIN Input High Level PLLIN = External Clock with Respect to GND l 2.8 V PLLIN Input Low Level PLLIN = External Clock with Respect to GND l 0.5 V
PGOOD Output
VPGL PGOOD Voltage Low IPGOOD = 2mA, VPGL with Respect to GND 0.02 0.04 V IPGOOD PGOOD Leakage Current VPGOOD = 3.3V 10 µA PGOOD Trip Level VFB with Respect to Set Regulated Voltage VFB Ramping Negative –13 –10 –7 % Hysteresis 2.5 % VFB with Respect to Set Regulated Voltage VFB Ramping Positive 7 10 13 % Hysteresis 2.5 % Delay for Reporting a Fault 40 µs
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 4:
The LTC3896 is tested in a feedback loop that servos VITH to a may cause permanent damage to the device. Exposure to any Absolute specified voltage and measures the resultant VFB. The specification at 85°C Maximum Rating condition for extended periods may affect device is not tested in production and is assured by design, characterization and reliability and lifetime. correlation to production testing at other temperatures (125°C for the
Note 2:
The LTC3896 is tested under pulsed load conditions such that T LTC3896E and LTC3896I, 150°C for the LTC3896H). For the LTC3896I J ≈ T and LTC3896H, the specification at 0°C is note tested in production and is A. The LTC3896E is guaranteed to meet performance specifications from 0°C to 85°C. Specifications over the –40°C to 125°C operating junction assured by design, characterization and correlation to production testing temperature range are assured by design, characterization and correlation at –40°C. with statistical process controls. The LTC3896I is guaranteed over the
Note 5:
Dynamic supply current is higher due to the gate charge being –40°C to 125°C operating junction temperature range and the LTC3896H delivered at the switching frequency. See the Applications Information is guaranteed over the –40°C to 150°C operating junction temperature section. range. Note that the maximum ambient temperature consistent with
Note 6:
Rise and fall times are measured using 10% and 90% levels. Delay these specifications is determined by specific operating conditions in times are measured using 50% levels. conjunction with board layout, the rated package thermal impedance
Note 7:
The minimum on-time condition is specified for an inductor and other environmental factors. High temperatures degrade operating peak-to-peak ripple current >40% of I lifetimes; operating lifetime is derated for junction temperatures greater MAX (see Minimum On-Time Considerations in the Applications Information section). than 125°C. The junction temperature (TJ, in °C) is calculated from the ambient temperature (T
Note 8:
Do not apply a voltage or current source to these pins. They must A, in °C) and power dissipation (PD, in Watts) according to the formula: be connected to capacitive loads only, otherwise permanent damage may T occur. J = TA + (PD • θJA) where θ
Note 9:
Do not apply a voltage or current source to the NDRV pin, other JA = 28°C/W for the TSSOP package.
Note 3:
This IC includes overtemperature protection that is intended to than tying NDRV to DRVCC when not used. If used it must be connected protect the device during momentary overload conditions. The maximum to capacitive loads only (see DRVCC Regulators (OPTI-DRIVE) in the rated junction temperature will be exceeded when this protection is active. Applications Information section), otherwise permanent damage may Continuous operation above the specified absolute maximum operating occur. junction temperature may impair device reliability or permanently damage
Note 10:
The minimum input supply (V – IN + |VOUT |) operating range is the device. dependent on the DRVCC UVLO thresholds as determined by the DRVUV pin setting. 3896f For more information www.linear.com/LTC3896 5 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts