Datasheet LTC7860 (Analog Devices) - 4

LTC7860
e lecTrical characTerisTics The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C. (Note 3) VIN = 12V, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
Programmable Switching Frequency RFREQ = 24.9kΩ 105 kHz RFREQ = 64.9kΩ 375 440 505 kHz RFREQ = 105kΩ 810 kHz Low Switching Frequency FREQ = 0V 320 350 380 kHz High Switching Frequency FREQ = Open 485 535 585 kHz fFOLD Foldback Frequency as Percentage of VFB = 0V, FREQ = 0V 18 % Programmable Frequency tON(MIN) Minimum On-Time 220 ns
Gate Driver
VCAP Gate Bias LDO Output Voltage (VIN-VCAP) IGATE = 0mA l 7.6 8.0 8.5 V RUP Gate Pull-Up Resistance Gate High 2 Ω RDN Gate Pull-Down Resistance Gate Low 0.9 Ω
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings statistical process controls. The LTC7860I is guaranteed to meet may cause permanent damage to the device. Exposure to any Absolute performance specifications over the –40°C to 125°C operating junction Maximum Rating condition for extended periods may affect device temperature range, the LTC7860H is guaranteed over the –40°C to 150°C reliability and lifetime. operating junction temperature range, and the LTC7860MP is guaranteed
Note 2:
The junction temperature (T and tested over the full –55°C to 150°C operating junction temperature J in °C) is calculated from the ambient temperature (T range. High junction temperatures degrade operating lifetimes; operating A in °C) and power dissipation (PD in Watts) as follows: T lifetime is derated for junction temperatures greater than 125°C. The J = TA + (PD • θJA) maximum ambient temperature consistent with these specifications is where θJA (in °C/W) is the package thermal impedance provided in the Pin determined by specific operating conditions in conjunction with board Configuration section for the corresponding package. layout, the rated package thermal impedance and other environmental
Note 3:
The LTC7860 is tested under pulsed load conditions such that TJ factors. ≈ TA. The LTC7860E is guaranteed to meet performance specifications
Note 4:
The LTC7860 is tested in a feedback loop that adjust V from 0°C to 85°C operating junction temperature range. The LTC7860E REG or (V specifications over the –40°C to 125°C operating junction temperature FB – VFBN) to achieve a specified error amplifier output voltage (on ITH pin). range are assured by design, characterization and correlation with 7860f 4 For more information www.linear.com/LTC7860