Datasheet LTC3704 (Analog Devices) - 3

LTC3704
ELECTRICAL CHARACTERISTICS The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25
°
C. VIN = VINTVCC = 5V, VRUN = 1.5V, RFREQ = 80k, VMODE/SYNC = 0V, unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Oscillator
fOSC Oscillator Frequency RFREQ = 80k 250 300 350 kHz Oscillator Frequency Range 50 1000 kHz DMAX Maximum Duty Cycle 87 92 97 % fSYNC/fOSC Recommended Maximum Synchronized fOSC = 300kHz (Note 6) 1.25 1.30 Frequency Ratio tSYNC(MIN) MODE/SYNC Minimum Input Pulse Width VSYNC = 0V to 5V 25 ns tSYNC(MAX) MODE/SYNC Maximum Input Pulse Width VSYNC = 0V to 5V 0.8/fOSC ns VIL(MODE) Low Level MODE/SYNC Input Voltage 0.3 V VIH(MODE) High Level MODE/SYNC Input Voltage 1.2 V RMODE/SYNC MODE/SYNC Input Pull-Down Resistance 50 kΩ VFREQ Nominal FREQ Pin Voltage 0.62 V
Low Dropout Regulator
VINTVCC INTVCC Regulator Output Voltage VIN = 7.5V 5.0 5.2 5.4 V ΔVINTVCC INTVCC Regulator Line Regulation 7.5V ≤ VIN ≤ 15V 8 25 mV ΔVIN1 ΔVINTVCC INTVCC Regulator Line Regulation 15V ≤ VIN ≤ 30V 70 200 mV ΔVIN2 VLDO(LOAD) INTVCC Load Regulation VIN = 7.5V, 0 ≤ IINTVCC ≤ 20mA – 2 – 0.2 % VDROPOUT INTVCC Regulator Dropout Voltage VINTVCC = Open, INTVCC Load = 20mA 280 mV IINTVCC Bootstrap Mode INTVCC Supply RUN = 0V, SENSE = 5V 10 20 μA Current in Shutdown
GATE Driver
tr GATE Driver Output Rise Time CL = 3300pF (Note 7) 17 100 ns tf GATE Driver Output Fall Time CL = 3300pF (Note 7) 8 100 ns
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 4:
The dynamic input supply current is higher due to power MOSFET may cause permanent damage to the device. Exposure to any Absolute gate charging (QG • fOSC). See Applications Information. Maximum Rating condition for extended periods may affect device
Note 5:
The LTC3704 is tested in a feedback loop that servos VNFB to the reliabilty and lifetime. reference voltage with the ITH pin forced to a voltage between 0V and 1.4V
Note 2:
The LTC3704E is guaranteed to meet performance specifications (the no load to full load operating voltage range for the ITH pin is 0.3V to from 0°C to 85°C. Specifications over the – 40°C to 85°C operating 1.23V). temperature range are assured by design, characterization and correlation
Note 6:
In a synchronized application, the internal slope compensation with statistical process controls. The LTC3704I is guaranteed over the full gain is increased by 25%. Synchronizing to a significantly higher ratio will –40°C to 125°C operating temperature range. reduce the effective amount of slope compensation, which could result in
Note 3:
TJ is calculated from the ambient temperature TA and power subharmonic oscillation for duty cycles greater than 50%. dissipation PD according to the following formula:
Note 7:
Rise and fall times are measured at 10% and 90% levels. TJ = TA + (PD • 120°C/W) 3704fb 3