描述 Description

The NCV8851-1 is an adjustable output, synchronous buck controller, which drives dual N-channel MOSFETs, ideal for high power applications. Average current mode control is employed for very fast transient response and tight regulation over wide input voltage and output load ranges. The IC incorporates an internal fixed 6.0 V low-dropout linear regulator (LDO), which supplies charge to the switch mode power supply's (SMPS) bottom gate driver, limiting the power lost to excess gate drive. The IC is designed for operation over a wide input voltage range (4.5 V to 40 V) and is capable of 10 to 1 voltage conversion at 500 kHz. Additional controller features include undervoltage lockout, internal soft start, low quiescent current sleep mode, programmable frequency, SYNC function, average current limiting, cycle-by-cycle overcurrent protection and thermal shutdown.

特性 Features

? Average current mode control
? Fast transient response and simple compensator design
? 0.8 V 2% reference voltage
? Tight tolerance on programmable output voltage
? Wide input voltage range of 4.5 V to 40 V
? Allows for direct regulation from car battery through load dump conditions
? 6.0 V low-dropout linear regulator (LDO)
? Supplies internal supply for gate drivers
? Input UVLO (Undervoltage Lockout)
? Disables start-up in undervoltage conditions
? Internal soft-start
? Lowers inrush current and avoids output overshoot during start-up
? 1.0 μA maximum quiescent current in sleep mode
? Very low sleep current
? Adaptive non-overlap circuitry
? Protects against switch cross-conduction (shoot-through)
? Programmable fixed frequency170 kHz to 500 kHz
? Allows for design flexibility
? External clock synchronization up to 600 kHz
? Allows for frequency synchronization and spread spectrum operation
? Average current limiting (ACL)
? Limits current to protect devices
? Cycle-by-cycle overcurrent protection (OCP)
? Protects components in case of a short-circuit and recovers
? Thermal shutdown (TSD)
? Thermally protects IC

應(yīng)用 Application

? Automotive systems requiring high current
? Pre-regulated supply for low-voltage SMPSs and LDOs
? Automotive systems

簡介

NCV8851-1屬于集成電路（IC）的線性穩(wěn)壓器控制器。由制造生產(chǎn)的NCV8851-1穩(wěn)壓器 - 線性 + 開關(guān)此產(chǎn)品族中的產(chǎn)品用于構(gòu)建執(zhí)行 DC-DC 轉(zhuǎn)換或電壓調(diào)節(jié)功能的電路，采用的是開關(guān)模式和線性穩(wěn)壓器功能的組合。雖然具體的拓撲各不相同，但此類產(chǎn)品的主要目的是將開關(guān)模式技術(shù)的效率優(yōu)勢與線性穩(wěn)壓技術(shù)的低噪聲特性結(jié)合在一起。