Datasheet LTC3839 (Analog Devices) - 4

LTC3839
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C. VIN = 15V unless otherwise noted (Note 3). SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VPLLIN(L) Clock Input Low Level Into MODE/PLLIN 0.5 V RMODE/PLLIN MODE/PLLIN Input Resistance With Respect to SGND 600 kΩ
Gate Drivers
RTG(UP)1,2 TG Driver Pull-Up On Resistance TG High 2.5 Ω RTG(DOWN)1,2 TG Driver Pull-Down On Resistance TG Low 1.2 Ω RBG(UP)1,2 BG Driver Pull-Up On Resistance BG High 2.5 Ω RBG(DOWN)1,2 BG Driver Pull-Down On Resistance BG Low 0.8 Ω tD(TG/BG)1,2 Top Gate Off to Bottom Gate On Delay Time (Note 6) 20 ns tD(BG/TG)1,2 Bottom Gate Off to Top Gate On Delay Time (Note 6) 15 ns
Internal VCC Regulator
VDRVCC1 Internally Regulated DRVCC1 Voltage 6V < VIN < 38V 5.0 5.3 5.6 V DRVCC1 Load Regulation IDRVCC1 = 0mA to –100mA –1.5 –3.5 % VEXTVCC EXTVCC Switchover Voltage EXTVCC Rising 4.4 4.6 4.8 V EXTVCC Switchover Hysteresis EXTVCC Falling from Switchover Voltage 200 mV EXTVCC to DRVCC2 Voltage Drop VEXTVCC = 5V, IDRVCC2 = –100mA 200 mV
PGood Output
OV PGOOD Overvoltage Threshold VOUT Rising, with Respect to Regulated Voltage 5 7.5 10 % UV PGOOD Undervoltage Threshold VOUT Falling, with Respect to Regulated Voltage –5 –7.5 –10 % PGOOD Threshold Hysteresis VOUT Returning to Reference Voltage 2 % VPGOOD(L) PGOOD Low Voltage IPGOOD = 2mA 0.1 0.3 V tD(PGOOD) Delay from VFB Fault (OV/UV) to PGOOD 50 µs Falling Delay from VFB Good to PGOOD Rising 20 µs
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 4:
This IC includes overtemperature protection that is intended to may cause permanent damage to the device. Exposure to any Absolute protect the device during momentary overload conditions. The maximum Maximum Rating condition for extended periods may affect device rated junction temperature will be exceeded when this protection is active. reliability and lifetime. Continuous operation above the specified absolute maximum operating
Note 2:
The junction temperature (T junction temperature may impair device reliability or permanently damage J, in °C) is calculated from the ambient temperature (T the device. A, in °C) and power dissipation (PD, in Watts) according to the formula:
Note 5:
The LTC3839 is tested in a feedback loop that adjusts the T differential feedback voltage (V + – V –) to J = TA + (PD • θJA) OUTSENSE OUTSENSE where θ achieve specified error amplifier output voltages (ITH). JA (in °C/W) is the package thermal impedance.
Note 3:
The LTC3839 is tested under pulsed loading conditions such that
Note 6:
Delay times are measured with top gate (TG) and bottom gate T (BG) driving minimum load, and using 50% levels. J ≈ TA. The LTC3839E is guaranteed to meet specifications over the 0°C to 85°C operating junction temperature range. Specifications over the
Note 7:
In order to simplify the total system error computation, the –40°C to 125°C operating junction temperature range are assured by regulated voltage is defined in one combined specification which includes design, characterization and correlation with statistical process controls. the effects of line, load and common mode variation. The combined The LTC3839I is guaranteed to meet specifications over the –40°C to regulated voltage specification is tested by independently varying line, 125°C operating junction temperature range . Note that the maximum load, and common mode, which by design do not significantly affect one ambient temperature consistent with these specifications is determined by another. For any combination of line, load, and common mode variation, specific operating conditions in conjunction with board layout, the rated the regulated voltage should be within the limits specified that are tested in package thermal impedance and other environmental factors. production to the following conditions: • Line: V – IN = 4.5V to 38V, ITH = 1.2V, VOUTSENSE = 0V • Load: V – IN = 15V, ITH = 0.5V to 1.9V, VOUTSENSE = 0V • Common mode: V – IN = 15V, ITH = 1.2V, VOUTSENSE = –500mV to 500mV 3839fa 4 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Typical Performance Characteristics Pin Functions Functional Diagram Operation Typical Applications Typical Application Related Parts