LM 36923 ORIGINAL Mobile Phone IC

Enhance Device Functionality with the LM 36923 IC

The LM 36923 ORIGINAL Mobile Phone IC is specifically designed to optimize your mobile device’s performance. Engineered with precision and reliability, this IC ensures seamless integration and efficient functionality. LM 36923 ORIGINAL Mobile Phone IC

Reliable and Original Component

This component is an original and high-quality integrated circuit, perfect for professionals and enthusiasts looking for dependable tech solutions. Its compatibility with various devices makes it a versatile choice for repairs or upgrades. LM 36923 ORIGINAL Mobile Phone IC

Why Choose the LM 36923?

The LM 36923 IC stands out for its durability, superior performance, and ease of use. Whether you’re a repair expert or a tech enthusiast, this IC provides the support you need to keep your mobile devices functioning flawlessly. LM 36923 ORIGINAL Mobile Phone IC

The LM36923 is a high-efficiency, triple-string white-LED driver specifically engineered for LCD display backlighting in modern mobile phones (popularly found in Huawei, Motorola, and Samsung models). Manufactured by Texas Instruments, this IC is a synchronous boost converter capable of driving up to 24 LEDs (8 per string) with extreme precision. LM 36923 ORIGINAL Mobile Phone IC

Below are the comprehensive technical specifications and operational details. LM 36923 ORIGINAL Mobile Phone IC

Technical Specifications: LM36923

Feature	Specification Details
Manufacturer	Texas Instruments
Primary Function	Triple-String White LED Backlight Driver
Topology	Step-Up (Boost) DC-DC Regulator
Input Voltage Range	$2.5\text{V}$ to $5.5\text{V}$ (Ideal for Li-ion batteries)
Output Voltage (Max)	Up to $29.5\text{V}$
Number of LED Strings	3 Parallel Strings
Current per String	$25\text{mA}$ (Maximum)
Switching Frequency	Selectable: $500\text{kHz}$ or $1\text{MHz}$
Dimming Resolution	11-Bit (Adjustable via $I^2C$ or PWM)
Peak Efficiency	Up to $91.6\%$
Operating Temp Range	$-40\text{°C}$ to $+85\text{°C}$
Package Type	12-Bump DSBGA ( $1.75\text{mm} \times 1.35\text{mm}$ )

Key Performance Features

Current Matching: Features $1\%$ matched current sinks across all strings, ensuring uniform brightness across the entire mobile screen.
Adaptive Regulation: The IC uses an adaptive method to regulate current, allowing for slight variations in forward voltage between different LED strings without losing efficiency.
Advanced Dimming: Supports both $I^2C$ digital programming and logic-level PWM input. The internal sensor maps PWM duty cycles to an 11-bit current, eliminating the “flicker” often seen in low-quality drivers.
Auto Switch Frequency: To save power during low-load conditions, the IC can automatically switch between $250\text{kHz}$ , $500\text{kHz}$ , and $1\text{MHz}$ modes.

Pin Configuration & Functional Description

The LM36923 is housed in a compact 12-bump DSBGA package. Understanding the pinout is critical for PCB repair or replacement:

Pin Name	Description
VIN	Power Supply Input ( $2.5\text{V} - 5.5\text{V}$ )
SW	Switching Node (Connects to the Inductor)
FB	Feedback pin for monitoring voltage/current
SCL / SDA	$I^2C$ Serial Clock and Data lines for programming
PWM / EN	Pulse Width Modulation input or Global Enable pin
OUT1, 2, 3	Current sink inputs for the 3 LED strings
GND	Ground reference

Protection Mechanisms

Designed for the high-reliability environment of mobile devices, the “Original” LM36923 includes several hardware-level safeguards:

Overvoltage Protection (OVP): Four configurable thresholds ( $17\text{V}$ , $21\text{V}$ , $25\text{V}$ , $29\text{V}$ ) to prevent damage if an LED string is disconnected.
Overcurrent Protection (OCP): Adjustable limits from $750\text{mA}$ to $1500\text{mA}$ .
Thermal Shutdown: Automatically powers down if the internal junction temperature exceeds safe limits.
Soft-Start: Prevents high inrush currents during the initial power-on phase of the mobile display.

Repair & Replacement Notes

In the mobile repair industry, the LM36923 is often referred to as the “Backlight IC.” When replacing this chip:

BGA Skills Required: Since it is a DSBGA (Ball Grid Array) package, professional micro-soldering tools and stencils are required for “reballing” or installation.
“Original” vs. Refurbished: Authentic TI chips (marked with specific laser-etched codes) offer higher efficiency and lower heat generation than generic equivalents.
Common Faults: If a phone has a “black screen” but still vibrates or makes sounds, this IC (or the associated boost inductor) is often the primary suspect.

LM 36923 ORIGINAL Mobile Phone IC