LM3492HCMH/NOPB屬于集成電路（IC）的LED驅(qū)動(dòng)器。由美國(guó)德州儀器公司制造生產(chǎn)的LM3492HCMH/NOPBLED 驅(qū)動(dòng)器器件屬于 LED 驅(qū)動(dòng)器電源管理集成電路 (PMIC) 系列，可通過(guò)標(biāo)稱固定電壓的電源為負(fù)載（通常為發(fā)光二極管）提供電流，并且電流可控。它與用于電壓調(diào)節(jié)的類似產(chǎn)品的主要區(qū)別在于，這類器件提供較低的反饋電壓（以提高系統(tǒng)能效），而且通?？蓪?duì)器件工作點(diǎn)進(jìn)行外部控制，可在照明應(yīng)用中用于實(shí)現(xiàn)調(diào)光功能。

1 Features

1? Boost Converter

– Automotive Grade Product, Q100 Grade-1

Qualified

– Very Wide Input Voltage Range: 4.5 V to 65 V

– Programmable Soft-Start Period

– No Loop Compensation Required

– Stable with Ceramic and Other Low ESR

Capacitors with No Audible Noise

– Nearly Constant Switching Frequency

Programmable from 200 kHz to 1 MHz

? Current Regulator

– Programmable LED Current: 50 mA to 250 mA

– 10000:1 Contrast Ratio, 300-ns Minimum

Pulse Width

– Two Individual Dimmable LED Strings up to

65 V, Total 15 W (Typically 28 LEDs at

150 mA)

– Dynamic Headroom Control Maximizes

Efficiency

– Over-Power Protection

– ±3% Current Accuracy

? Supervisory Functions

– Precision Enable

– COMM I/O Pin for Diagnostic and Commands

– Thermal Shutdown Protection

– Thermally Enhanced PWP, 20-Pin Package

2 Applications

? Ultra-High Contrast Ratio 6.5” to 10” LCD Display

Backlight up to 28 LEDs

? Automotive or Marine GPS Display

3 Description

The LM3492HC/-Q1 device integrates a boost converter and a two-channel current regulator to

implement a highly efficient and cost effective LED

driver. This device drives two individually dimmable

LED strings with a maximum power of 15 W and an

output voltage of up to 65 V. The boost converter

employs a proprietary projected-on-time control

method to give a fast transient response with no

compensation required. The nearly constant

switching frequency can be set to a level from 200

kHz to 1 MHz. Ceramic capacitors stabilize the

application circuit and produce no audible noise on

dimming. The programmable peak current limit and

soft-start features reduce current surges at start-up.

An integrated, 190-mΩ, 3.9-A, N-Channel MOSFET

switch minimizes the solution size. The fast slew rate

current regulator allows high frequency and narrow

pulse width dimming signals to achieve a very high contrast ratio of 10000:1. The LED current can be set

from 50 mA to 250 mA by a single resistor.