Datasheet LT1766, LT1766-5 (Analog Devices) - 5

LT1766/LT1766-5
ELECTRICAL CHARACTERISTICS (LT1766H Grade) The
l
denotes specifi cations which apply over the full operating temperature range, otherwise specifi cations are at TJ = 25°C. VIN = 15V, VC = 1.5V, SHDN = 1V, BOOST open circuit, SW open circuit, unless otherwise noted. PARAMETER CONDITIONS MIN TYP MAX UNITS
fSW Line Regulation 5.5V ≤ VIN ≤ 60V l 0.05 0.15 %/V fSW Frequency Shifting Threshold Df = 10kHz 0.8 V Minimum Input Voltage (Note 3) l 4.6 5.5 V Minimum Boost Voltage (Note 4) ISW ≤ 0.75A l 1.8 3 V Boost Current (Note 5) Boost = VIN + 5V, ISW = 0.5A l 12 40 mA Boost = VIN + 5V, ISW = 0.75A l 45 100 mA Input Supply Current (IVIN) (Note 6) VBIAS = 5V 1.4 2.2 mA Bias Supply Current (IBIAS) (Note 6) VBIAS = 5V 2.9 4.2 mA Shutdown Supply Current SHDN = 0V, VIN ≤ 60V, SW = 0V, VC Open 25 120 μA l 500 μA Lockout Threshold VC Open l 2.3 2.42 2.68 V Shutdown Thresholds VC Open, Shutting Down l 0.15 0.37 0.9 V VC Open, Starting Up l 0.25 0.45 0.9 V Minimum SYNC Amplitude l 1.5 2.2 V SYNC Frequency Range 228 700 kHz SYNC Input Resistance 20 kΩ
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 7:
Switch on-resistance is calculated by dividing VIN to SW voltage may cause permanent damage to the device. Exposure to any Absolute by the forced current. See Typical Performance Characteristics for the Maximum Rating condition for extended periods may affect device graph of switch voltage at other currents. reliability and lifetime.
Note 8:
The LT1766EGN, LT1766EGN-5, LT1766EFE and LT1766EFE-5
Note 2:
Gain is measured with a VC swing equal to 200mV above the low are guaranteed to meet performance specifi cations from 0°C to 125°C clamp level to 200mV below the upper clamp level. junction temperature. Specifi cations over the –40°C to 125°C operating
Note 3:
Minimum input voltage is not measured directly, but is guaranteed junction temperature range are assured by design, characterization and by other tests. It is defi ned as the voltage where internal bias lines are still correlation with statistical process controls. The LT1766IGN, LT1766IGN-5, regulated so that the reference voltage and oscillator remain constant. LT1766IFE and LT1766IFE-5 are guaranteed over the full –40°C to 125°C Actual minimum input voltage to maintain a regulated output will depend operating junction temperature range. The LT1766HGN and LT1766HFE are upon output voltage and load current. See Applications Information. guaranteed over the full –40°C to 140°C operating junction temperature
Note 4:
This is the minimum voltage across the boost capacitor needed to range. guarantee full saturation of the internal power switch.
Note 9:
Transconductance and voltage gain refer to the internal amplifi er
Note 5:
Boost current is the current fl owing into the BOOST pin with the exclusive of the voltage divider. To calculate gain and transconductance, pin held 5V above input voltage. It fl ows only during switch on time. refer to the SENSE pin on fi xed voltage parts. Divide the values shown by the ratio V
Note 6:
Input supply current is the quiescent current drawn by the input OUT/1.219. pin when the BIAS pin is held at 5V with switching disabled. Bias supply
Note 10:
This IC includes overtemperature protection that is intended current is the current drawn by the BIAS pin when the BIAS pin is held to protect the device during momentary overload conditions. Junction at 5V. Total input referred supply current is calculated by summing input temperature will exceed 140°C when overtemperature protection is active. supply current (I Continuous operation above the specifi ed maximum operating junction VIN) with a fraction of bias supply current (IBIAS): temperature may impair device reliability. ITOTAL = IVIN + (IBIAS)(VOUT/VIN)
Note 11:
High junction temperatures degrade operating lifetimes. with VIN = 15V, VOUT = 5V, IVIN = 1.4mA, IBIAS = 2.9mA, ITOTAL = 2.4mA. Operating lifetime at junction temperatures between 125°C and 140°C is derated to 1000 hours. 1766fc 5