is a highly integrated Embedded Controller (EC) primarily used for laptop keyboard management and system-level monitoring. A "solid feature" to highlight in its datasheet is the Direct Battery Management with SentinelAlert!
, which allows the controller to monitor critical system health—such as temperature and battery voltage—independently of the main processor. Key Feature Highlights for KBC1126NU Intelligent Keyboard Management
: Specialized hardware for scanning complex key matrices and supporting N-key rollover
, which is essential for preventing ghosting in high-performance or gaming laptops. SentinelAlert! System Monitoring
: Provides an autonomous analog monitoring system featuring an 8-channel ADC 3-channel DAC . It can trigger a HW_PROTECT#
thermal event signal without requiring firmware intervention, ensuring system safety even if the main OS hangs. Legacy Host Interface Emulation : Emulates the classic 8042-style host interface
(Port 92 support), ensuring compatibility with legacy software and operating systems while operating on a modern LPC (Low Pin Count) interface Power Efficiency : Supports Connected Standby
modes, making it ideal for mobile devices that need to remain responsive while maintaining low power consumption. Flexible I/O and Peripheral Control : Includes dedicated LED drivers
, multiple GPIOs, and support for external PS/2 devices, allowing for a highly customizable laptop deck (e.g., backlit keys and status indicators). Technical Summary Specification/Detail LPC (Low Pin Count) Monitoring 8-channel, 10-bit ADC Protection Hardware-based thermal event indication ( HW_PROTECT# 156-pin DQFN or 128-pin TQFP (variant dependent)
For full technical specifications and pinout diagrams, you can refer to the KBC1126NU Datasheet on AllDatasheet Microchip’s product listings pin description section for your datasheet? AI responses may include mistakes. Learn more MEC APP Firmware - Microchip Technology
KBC1126-NU Keyboard Controller (KBC) and Super I/O integrated circuit manufactured by (now part of Microchip Technology
. It is commonly found in laptop motherboards, such as those from Dell and HP. Technical Overview
It manages low-level system functions including keyboard input, touchpad interfacing, thermal monitoring (fan control), and power sequencing. Package Type: It typically comes in a 156-pin VFQFN
(Exposed Pad) package designed for surface mounting (SMD/SMT). Related Models: It is part of a family that includes the
, which also features integrated ADC and DAC capabilities with "SentinelAlert" for mobile power management. Datasheet & Support kbc1126nu datasheet hot
Finding a full public datasheet for this specific chip can be difficult as SMSC often restricted these documents to OEMs. However, you can find technical summaries and pinout information through the following resources: Datasheet Repositories: Preliminary data and package specs are often hosted on AllDatasheet Jotrin Electronics Inventory & Pricing: For current stock levels or procurement, sites like Win-Source
provide availability status, though supply for this specific part is often limited. Troubleshooting "Hot" Issues If your KBC1126-NU chip is running physically , it usually indicates a hardware failure: Internal Short:
The chip may have failed internally, drawing excessive current. External Short:
A shorted capacitor or component on one of its power rails (often the +3.3V_ALW or +5V_ALW lines) can cause the controller to overheat. Power Surge:
Overvoltage from a faulty power adapter or charging circuit can damage the chip's internal logic.
Summary report — KBC1126NU datasheet (hot)
What it is: KBC1126NU (aka KBC1126-NU) — a mobile KBC / Super I/O style IC listed under SMSC/Microchip product families; available in QFP/TQFP-128 packages per distributor listings.
Sources found quickly: multiple datasheet/stock pages (alldatasheet, ic2ic, iccomponents/sellers, Scribd uploads). No authoritative manufacturer PDF hosted on an obvious official product page was found in the top search hits.
Key searchable identifiers from listings:
Likely content in the datasheet (based on similar KBC devices / search snippets):
Availability / stock signals:
Next actions (recommended):
If you want, I can now fetch and extract pinout, electrical specs, and block diagram from a selected PDF. Which source should I use?
The SMSC KBC1126NU is a specialized keyboard controller (KBC) typically used in laptops and mobile computing devices. It integrates several "Super I/O" functions, such as keyboard scanning, system power management, and analog-to-digital conversion, into a single chip. Key Specifications & Features is a highly integrated Embedded Controller (EC) primarily
Based on the documentation for the KBC1126 series, key features often include:
Integrated Functions: Combines a 8051-based microcontroller core with system-level functions like LPC bus interface, keyboard scan matrix, and PS/2 support.
System Management: Handles low-level power states (ACPI compliance), thermal monitoring, and battery management tasks.
SentinelAlert: SMSC’s proprietary technology designed to monitor system health and provide alerts for potential failures.
Package Type: Typically found in a compact, surface-mount package (e.g., TQFP or QFN) suitable for laptop motherboards. Common Use Cases
Laptop Repair: Often a target for replacement when a laptop fails to power on, has keyboard "ghosting" issues, or experiences fan control failures.
Firmware Programming: In some repair scenarios, the internal flash of the KBC1126NU might need to be reprogrammed using specialized tools (like an RT809H programmer) if the BIOS/EC firmware is corrupted. Technical Resources
You can find more detailed pinouts and electrical characteristics through distributors and datasheet archives:
Datasheet Downloads: High-level summaries and full PDFs are available on ALLDATASHEET.COM and ic2ic.com.
Stock & Sourcing: Retailers like Amazon.in and specialized electronics vendors like WIN-SOURCE or Jotrin Electronics provide images and availability for the physical chip. KBC1126NU stock, price, datasheet. – ic2ic.com
Microtranik,Components,Inc. KBC1126NU. Distributor. for more pls inquire us now. 150750. 17+RoHS. New instock, best quality. 2026- KBC1126NU Datasheet, PDF - ALLDATASHEET.COM
SMSC (now Microchip) KBC1126-NU is a specialized Mobile Keyboard Controller (KBC) typically used in laptop motherboards for power management, keyboard matrix scanning, and low-level system communication. If your KBC1126-NU chip is running physically hot
, it usually indicates a hardware failure such as a short circuit in the chip itself or a power rail issue (overvoltage/leakage) on the motherboard. Technical Specifications Summary
The KBC1126-NU belongs to the SMSC Mobile KBC family and is housed in a 128-pin TQFP package . Key features typically found in this series include: www.jotrin.ru Processor: What it is: KBC1126NU (aka KBC1126-NU) — a
Integrated 8051-based or proprietary microcontroller core for managing ACPI power states. Interfaces: LPC Interface: Communication with the PCH/Southbridge. SMBus/I2C: For battery management and thermal sensor monitoring. For legacy keyboard and touchpad support. Power Management:
Controls S0-S5 power states, power-on sequencing, and fan PWM control. Used for monitoring battery voltage and temperature. AliExpress Troubleshooting "Hot" Chip Issues
When this chip overheats, it often leads to symptoms like the laptop not turning on, "dead" keyboard/trackpad, or the battery not charging. Check for Shorts: Use a multimeter to check the resistance to ground on the (Power) and
pins. A very low resistance (below 10–20 ohms) often indicates a dead chip. Verify Voltage Rails:
Ensure the chip is receiving the correct 3.3V supply. If the voltage regulator (usually the 3.3V/5V "Always-On" standby IC) is failing, it may be sending excessive voltage to the KBC. Peripheral Shorts:
A shorted keyboard, touchpad, or even a USB port managed by the KBC can cause it to draw excessive current and heat up. Try disconnecting all peripherals and see if it remains hot. Firmware (EC ROM):
While heat is usually electrical, sometimes a corrupted EC firmware can cause the processor to "loop" at high clock speeds, though this rarely makes it untouchable. Replacement & Resources Datasheet Access:
While full detailed datasheets for KBC chips are often under NDA, condensed versions and pinouts can be found on sites like Alldatasheet Programming: Most KBC1126-NU chips require internal programming
. If you replace the physical chip, you may need a specialized programmer (like the SVOD or Vertyanov) to flash the EC firmware into the new chip's internal memory for the laptop to boot. KBC1126NU stock, price, datasheet. – ic2ic.com
Temperature Check:
Current Draw Test:
Diode Mode Measurement:
| Part Number | Temperature | Package | |-------------|-------------|---------| | KBC1126NU-C | 0°C to +70°C | 128 LQFP | | KBC1126NU-I | -40°C to +85°C | 128 LQFP |
Rows: Pins 20–35 (ROW0 to ROW15) Columns: Pins 36–51 (COL0 to COL15)
If a diode is missing in the keyboard membrane, the KBC1126NU sees a phantom voltage. The datasheet specifies a pull-up resistor (10kΩ) on each column. Missing resistors = "hot" logic contention = melted traces.
