Datasheet LTC3807 (Analog Devices) - 10

ManufacturerAnalog Devices
DescriptionLow IQ, Synchronous Step-Down Controller with 24V Output Voltage Capability
Pages / Page34 / 10 — PIN FUNCTIONS EXTVCC (Pin 15/Pin 17):. TRACK/SS (Pin 19/Pin 1):. PGND …
File Format / SizePDF / 572 Kb
Document LanguageEnglish

PIN FUNCTIONS EXTVCC (Pin 15/Pin 17):. TRACK/SS (Pin 19/Pin 1):. PGND (Pin 16/Pin 18):. FREQ (Pin 20/Pin 2):

PIN FUNCTIONS EXTVCC (Pin 15/Pin 17): TRACK/SS (Pin 19/Pin 1): PGND (Pin 16/Pin 18): FREQ (Pin 20/Pin 2):

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LTC3807
PIN FUNCTIONS EXTVCC (Pin 15/Pin 17):
External Power Input to an
TRACK/SS (Pin 19/Pin 1):
External Tracking and Soft-Start Internal LDO Connected to INTVCC. This LDO supplies Input. The LTC3807 regulates the VFB voltage to the smaller INTVCC power, bypassing the internal LDO powered from of 0.8V or the voltage on the TRACK/SS pin. An internal VIN whenever EXTVCC is higher than 4.7V. See EXTVCC 10μA pull-up current source is connected to this pin. A Connection in the Applications Information section. Do capacitor to ground at this pin sets the ramp time to final not float or exceed 14V on this pin. Connect to ground regulated output voltage. Alternatively, a resistor divider (SGND or PGND) if not used. on another voltage supply connected to this pin allows the LTC3807 output to track another supply during start-up.
PGND (Pin 16/Pin 18):
Driver Power Ground. Connects to the source of bottom (synchronous) N-channel MOSFET
FREQ (Pin 20/Pin 2):
The frequency control pin for the and the (–) terminal of CIN. internal VCO. Connecting the pin to GND forces the VCO to a fixed low frequency of 350kHz. Connecting the pin
VIN (Pin 17/Pin 19):
Main Supply Pin. A bypass capacitor to INTV should be tied between this pin and the SGND pins. CC forces the VCO to a fixed high frequency of 535kHz. Other frequencies between 50kHz and 900kHz
ILIM (Pin 18/Pin 20):
Current Comparator Sense Voltage can be programmed by using a resistor between FREQ Range Inputs. Tying this pin to SGND, FLOAT or INTVCC and GND. An internal 20µA pull-up current develops the sets the maximum current sense threshold to one of three voltage to be used by the VCO to control the frequency. different levels for the comparator. 3807fa 10 For more information www.linear.com/LTC3807 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Package Description Typical Application Related Parts Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Package Description Revision History Related Parts