Datasheet LTC3618 (Analog Devices) - 4

LTC3618
e lecTrical characTerisTics The
l
denotes the specifications which apply over the full operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2), SVIN = PVINx = 3.3V, RT = 178k, unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VMODE VMODE High Voltage Pulse-Skipping Mode 1.0 V (Note 8) VMODE Low Voltage Forced Continuous Mode 0.4 V PGOOD1 Power Good Voltage Window of TRACK/SS1 = SVIN, Entering Window VDDQ VFB1 Ramping Up –5 –2 % VFB1 Ramping Down 2 5 % TRACK/SS1 = SVIN, Leaving Window VFB1 Ramping Up 8 10.5 % VFB1 Ramping Down –10.5 –8 % PGOOD2 Power Good Voltage Window of VTT Entering Window VTT Ramping Up –5 –2.5 % VTT Ramping Down 2.5 5 % Leaving Window VFB2 Ramping Up 8 10.5 % VFB2 Ramping Down –10.5 –8 % tPGOOD Power Good Blanking Time Entering/Leaving Window 65 105 140 µs RPGOOD Power Good Pull-Down On-Resistance I = 10mA 8 12 30 Ω VRUN VRUN Voltage Input High l 1 V Input Low l 0.4 V Pull-Down Resistance 4 MΩ
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 4:
External compensation on ITH pin. may cause permanent damage to the device. Exposure to any Absolute
Note 5:
Dynamic supply current is higher due to the internal gate charge Maximum Rating condition for extended periods may affect device being delivered at the switching frequency. reliability and lifetime.
Note 6:
See description of the TRACK/SS pin in the Pin Functions section.
Note 2:
The LTC3618 is tested under pulsed load conditions such that
Note 7:
When sourcing current, the average output current is defined TJ ≈ TA. The LTC3618E is guaranteed to meet performance specifications as flowing out of the SW pin. When sinking current, the average output over the 0°C to 85°C operating junction temperature range. Specifications current is defined as flowing into the SW pin. Sinking mode requires the over the –40°C to 125°C operating junction temperature range are use of forced continuous mode. assured by design, characterization and correlation with statistical process controls. The LTC3618I is guaranteed to meet specifications over the
Note 8:
See description of the MODE pin in the Pin Functions section. full –40°C to 125°C operating junction temperature range. Note that the
Note 9:
Guaranteed by design and correlation to wafer level measurements maximum ambient temperature consistent with these specifications is for QFN packages. determined by specific operating conditions in conjunction with board
Note 10:
This IC includes overtemperature protection that is intended layout, the rated package thermal resistance and other environmental to protect the device during momentary overload conditions. Junction factors. The junction temperature (TJ, in °C) is calculated from the ambient temperature will exceed 125°C when overtemperature protection is active. temperature (TA, in °C) and power dissipation (PD, in watts) according to Continuous operation above the specified maximum operating junction the formula: temperature may impair device reliability or permanently damage the T device. J = TA + (PD • θJA) where θJA (in °C/W) is the package thermal impedance.
Note 3:
This parameter is tested in a feedback loop which servos VFB1 to the midpoint for the error amplifier (VITH1 = 0.75V). 3618fc 4 For more information www.linear.com/LTC3618 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 Typical Applications Package Description Revision History Typical Application Related Parts