The HY2120-MB is a dual-section protection IC designed for 2-cell lithium-ion/lithium-polymer battery packs. 

It provides comprehensive safety features and precise voltage/current monitoring for rechargeable battery systems. 

Below is a detailed breakdown of its functions and applications:

Functions

1. High-Precision Voltage Detection
   • Overcharge Protection: Monitors each cell's voltage with adjustable thresholds (4.10V–4.50V ±25mV accuracy) .
   •  When a cell exceeds the set voltage, it triggers a cutoff to prevent overcharging.
   • Overdischarge Protection: Detects cell voltages below a programmable range (2.00V–3.00V ±80mV accuracy)  
   • and disconnects the load to avoid deep discharge.
   • Overcurrent and Short-Circuit Protection: Features fixed load short-circuit detection at 1.0V (±0.4V accuracy) , 
   • with fast response times (250μs typical) to protect against excessive currents.
2. Internal Delay Settings
   • Built-in delays eliminate the need for external components:
     • Overcharge detection delay: ~100ms typical
     • Overdischarge detection delay: ~110ms typical
     • Short-circuit detection delay: ~250μs typical .
3. Low Power Consumption
   • Active Mode: Typical current consumption is 5.0μA (max 9.0μA at VDD=7.8V) .
   • Sleep Mode: Ultra-low standby current (<0.1μA at VDD=4.0V) .
4. Wide Voltage and Temperature Range
   • Operates from 1.5V to 10V 812, suitable for 2-cell Li-ion/Li-polymer batteries (nominal 7.4V).
   • Supports extreme temperatures: -40°C to +85°C for operation and -40°C to +125°C for storage .
5. Selectable Features
   • Configurable overcharge/overdischarge release voltages (e.g., 3.90V–4.30V for overcharge release) .
   • Optional 0V battery charging support (check product documentation for settings) .
6. Robust Design
   • High-voltage tolerance (20V on charger-connected pins) .
   • Halogen-free and RoHS-compliant .
   • 
     

Applications

1. Portable Electronics
   • Power banks, wireless earbuds, and handheld gaming consoles needing extended runtime with 7.4V batteries.
   • Example: Electric toothbrushes (e.g., models using HY2120-GB, a similar variant) .
2. Power Tools
   • Cordless drills, screwdrivers, and garden equipment relying on 2-cell Li-ion batteries for high power output.
3. Industrial Equipment
   • IoT sensors, remote controls, and medical devices requiring reliable battery management in harsh environments.
4. Small-Scale Energy Storage
   • Backup power systems, LED lighting, and smart home devices with dual-cell battery packs.
5. Automotive Accessories
   • Car dash cams, tire inflators, and emergency jump starters using 2-cell batteries.

Technical Specifications

Package and Pinout

• Package: SOT23-6 (standard for compact designs) 812.
• Pins:
  • VDD: Power supply.
  • CO: Charge control output.
  • DO: Discharge control output.
  • VM: Voltage monitoring input.
  • GND: Ground.
  • NC: No connection.

  • HY2120-LB	SOT-23-6	4.250 V
    HY2120-MB	SOT-23-6	4.450 V
    HY2120-NB	SOT-23-6	4.280 V
    HY2120-OB	SOT-23-6	4.250 V
    HY2120-PB	SOT-23-6	4.250 V
    HY2120-RB	SOT-23-6	4.400 V
    HY2120-SB	SOT-23-6	4.450 V
    HY2120-ZB	SOT-23-6	4.250 V
    HY2120MA-B1A	SOT-23-6	4.450 V
    HY2120ZB-B1A	SOT-23-6	4.250 V
    HY2120SA-B1A	SOT-23-6	4.450 V
    HY2120ZC-B1D	SOT-23-6	4.230 V
    HY2120ZD-B1D	SOT-23-6	4.225 V
    HY2120ZD-B1A	SOT-23-6	4.250 V
    HY2120ZE-B1C	SOT-23-6	4.425 V
    HY2120ZF-B1C	SOT-23-6	4.475 V
    HY2120ZG-B1C	SOT-23-6	4.475 V
    HY2120ZH-B1D	SOT-23-6	4.175 V
    HY2120ZI-B1K	SOT-23-6	4.475 V
    HY2120ZJ-B1B	SOT-23-6	4.250 V
    HY2120PA-B1B	SOT-23-6	4.250 V
    HY2122-AB1A	SOT-23-6	3.650 V
    HY2122-AB1B	SOT-23-6	3.650 V
    HY2122-BB1A	SOT-23-6	3.750 V
    HY2122-EB1A	SOT-23-6	3.900 V
    HY2122-FB1A	SOT-23-6	3.650 V
    HY2122-GB1A	SOT-23-6	3.800 V

    
    

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