ZHCSO29 July 2021 LP5890
PRODUCTION DATA
- 1 特性
- 2 應(yīng)用
- 3 說明
- 4 Revision History
- 5 說明（續(xù)）
- 6 Pin Configuration and Functions
- 7 Specifications
-
8 Detailed Description
- 8.1 Overview
- 8.2 Functional Block Diagram
- 8.3
Feature Description
- 8.3.1 Independent and Stackable Mode
- 8.3.2 Current Setting
- 8.3.3 Frequency Multiplier
- 8.3.4 Line Transitioning Sequence
- 8.3.5 Protections and Diagnostics
- 8.4 Device Functional Modes
- 8.5 Continuous Clock Series Interface
- 8.6 PWM Grayscale Control
- 8.7 Register Maps
- 9 Application and Implementation
- 10Power Supply Recommendations
- 11Layout
- 12Device and Documentation Support
- 13Mechanical, Packaging, and Orderable Information
封裝選項
機械數(shù)據(jù) (封裝 | 引腳)
散熱焊盤機械數(shù)據(jù) (封裝 | 引腳)
- RRF|76
訂購信息
8.3.2.1 Brightness Control (BC) Function
The LP5890 device is able to adjust the output current of all constant-current outputs simultaneously. This function is called global brightness control (BC). The global BC for all outputs is programmed with a 3-bit register, thus all output currents can be adjusted in 8 steps for a given current-programming resistor, RIREF. When the 3-bit BC register changes, the gain of output current, GAINBC changes as Table 8-2 below.
| BC Register (BC) | Current Gain (GAINBC) |
|---|---|
| 000b | 24.17 |
| 001b | 30.57 |
| 010b | 49.49 |
| 011b (default) | 86.61 |
| 100b | 103.94 |
| 101b | 129.92 |
| 110b | 148.48 |
| 111b | 173.23 |
The maximum output current per channel, IOUTSET, is determined by resistor, RIREF, and the GAINBC. The voltage on IREF is typically 0.8 V. RIREF can be calculated by Equation 1 below. For noise immunity purpose, suggest RIREF < 40 kΩ.
