Datasheet LTC3815 (Analog Devices) - 5

LTC3815
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, VIN = 3.3V unless otherwise noted. (Note 2) SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Temperature Readback
N Resolution 9 Bits LSB Step Size 1 °C VF/S Full Scale Temperature ±256 °C TTUE Total Unadjusted Error ±3 °C tCONVERT Conversion Time 40 ms
PMBus Interface Parameters
VIH, SDA, SCL Input High Voltage 2.1 V VIL, SDA, SCL Input Low Voltage 0.8 V IIH, SDA, SCL Input Leakage Current 0V ≤ VPIN ≤ 5.5V –5 5 µA VOL, SDA Output Low Voltage (SDA) ISDA = 3mA 0.4 V VOL, ALERT Output Low Voltage (ALERT) IALERT = 1mA 0.4 V fSCL Serial Bus Operating Frequency 10 400 kHz tBUF Bus Free Time Between Stop and Start 1.3 µs Condition tHD_SDA Hold Time After (Repeated) Start Condition 0.6 µs tSU_SDA Repeated Start Condition Setup Time 0.6 µs tSU_STO Stop Condition Setup Time 0.6 µs tHD_DAT(OUT) Data Hold Time 300 900 ns tHD_DAT(IN) Input Data Hold Time 0 ns tSU_DAT Data Set-Up Time 100 ns tLOW Clock Low Period 1.3 10000 µs tHIGH Clock High Period 0.6 µs tTIMEOUT_SMB Stuck PMBus Timer Measured from Last PMBus Start 30 ms Event
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 4 :
The dynamic input supply current is higher due to power may cause permanent damage to the device. Exposure to any Absolute MOSFET gate charging (QG × fOSC). See applications Information for more Maximum Rating condition for extended periods may affect device information. reliability and lifetime.
Note 5:
The LTC3815 is tested in a feedback loop that servos VFB to a
Note 2:
The LTC3815 is tested under pulsed load conditions such that TJ ≈ TA. referenced voltage with the ITH pin forced to a voltage between 0.6V The LTC3815E is guaranteed to meet specifications from 0°C to 85°C and 1V. junction temperature. Specifications over the –40°C to 125°C operating
Note 6:
Guaranteed by design, not subject to test. junction temperature range are assured by design, characterization and
Note 7:
This IC includes overtemperature protection that is intended correlation with statistical process controls. The LTC3815I is guaranteed to protect the device during momentary overload conditions. Junction over the –40°C to 125°C operating junction temperature range. Note that temperature will exceed 125°C when overtemperature protection is active. the maximum ambient temperature consistent with these specifications Continuous operation above the specified maximum junction temperature is determined by specific operating conditions in conjunction with board may impair device reliability or permanently damage the device. layout, the rated package thermal impedance and other environmental factors.
Note 8:
The LTC3815 uses valley current mode control so the current limits specified correspond to the valley of the inductor current waveform.
Note 3:
The junction temperature (TJ, in °C) is calculated from the ambient Maximum load current is higher and equals the valley current limit I temperature (T LIM A, in °C) and power dissipation (PD, in Watts) according to plus one half of the inductor ripple current. the formula:
Note 9:
The maximum input and output voltage is 5.5V. TJ = TA + (PD • θJA)
Note 10:
Total output accuracy is the sum of the tolerances of IREF, where θ R JA (in °C/W) is the package thermal impedance. REF(EXTERNAL), ΔVOUT,OFFSET, and ΔIREF,LINE • ΔVIN. Rev B For more information www.analog.com 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 PMBus Command Details Typical Applications Package Description Revision History Typical Application Related Parts