Datasheet LTC3704 (Analog Devices) - 3

ManufacturerAnalog Devices
DescriptionWide Input Range, No RSENSE™ Positive-to-Negative DC/DC Controller
Pages / Page28 / 3 — ELECTRICAL CHARACTERISTICS. The
File Format / SizePDF / 333 Kb
Document LanguageEnglish

ELECTRICAL CHARACTERISTICS. The

ELECTRICAL CHARACTERISTICS The

Model Line for this Datasheet

Text Version of Document

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