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Part No.	LTC3786_15
Manufacturer	LINER
Size	407 Kbytes
Pages	34 pages
Description	Low IQ Synchronous Boost Controller

Datasheet Summary with AI

1. Introduction and Overview

️· This document is an excerpt from the LTC3786 datasheet.
️· The LTC3786 is a power management IC.
️· The datasheet describes electrical characteristics and operating parameters of the device.
️· Emphasis on junction temperature and its relation to ambient temperature.

2. Key Electrical Characteristics (Highlights - with critical parameters)

a) General Operating Parameters:

️· UVLO (Undervoltage Lockout): Thresholds for INTVCC to start and stop operation.
- Ramping Up: 3.6V - 4.1V
- Ramping Down: 3.8V - 4.3V
️· RUN Pin: On threshold: 1.18V - 1.38V. Hysteresis: 100mV.
️· Soft-Start: Charge current (ISS): 7-13µA.
️· PGOOD Output: Trip level, delay time.
- Low: 0.2V
- Delay: 25µs
️· BOOST Charge Pump: Available Current at SW = 12V, Boost-SW = 4.5V, Freq=0V. 85µA

b) Oscillator & Phase-Locked Loop (PLL)

️· Programmable Frequency (fPROG): Dependent on external resistor. Ranges from 105kHz to 760kHz.
️· Lowest Fixed Frequency: 320-380kHz
️· Highest Fixed Frequency: 485-585 kHz
️· Synchronizable Frequency: 75-850kHz.

c) Feedback and Control

️· Error Amplifier Transconductance (gm): 2 mmho.
️· Input DC Supply Current: VFB = 1.25V.
- Pulse-Skipping or Forced Continuous Mode: 0.8mA
- Shutdown: 80µA
️· Maximum Current Sense Threshold (VSENSE(MAX)): 68-82mV.
️· SENSE Pin Current: 200-300µA.

d) Timing Parameters (Switching)

️· Top/Bottom Gate Rise/Fall Times: ~20ns (measured with 10%/90% levels).
️· Top/Bottom Gate Pull-Up/Down Resistance: ~1.2Ω
️· Minimum On-Time (tON(MIN)): 110ns.

3. Key Tables & Parameters Summarized

️· Table 1: Absolute Maximum Ratings (Not fully included, but important for operational limits).
️· Table 3: General Operating Parameters (The most comprehensive table of electrical characteristics).
️· Table 2: Electrical Characteristics (Conditions: TA = 25°C, VBIAS = 12V unless otherwise noted) (Highlights oscillator parameters and feedback loop)
️· fPROG vs. Resistor (Defines programmable frequency range based on external resistor value)
️· tON(MIN): Defines the minimum on-time for the gate drivers.

4. Important Notes & Considerations

️· Junction Temperature (TJ): Critical for reliable operation. It's directly related to ambient temperature and power dissipation. Formula provided: TJ = TA + (PD - θJA)
️· Over Temperature Protection: Intended for momentary overload only.
️· Minimum On-Time: Limited by the minimum on-time requirement, affecting control loop stability.

Disclaimer: This is a summary based *only* on the provided text. Refer to the complete LTC3786 datasheet for full specifications, application information, and design considerations.