Battery charge controller HQ LTH7 with thermostat — Li‑Ion charge regulator HQ LTH7

HQ LTH7 is a Li‑Ion battery charge controller with an integrated thermostat that provides temperature‑aware charging control. It is a PMIC charger controller in a SOT23-5 package, designed to regulate charge current and terminate charging at the correct voltage to protect Li‑Ion cells. Input voltage range is 4.25–6.5 V, maximum charge voltage is 4.2 V and nominal output charging current is 150 mA. The controller is compatible with a range of charger ICs and reference designs for small battery systems.

Advantages

The HQ LTH7 integrates thermostat-based temperature monitoring with a Li‑Ion charge regulator to reduce the risk of charging outside safe temperature ranges. Its compact SOT23-5 package and PMIC architecture allow simple integration into portable devices and custom battery packs. The device supports precise charge termination at 4.2 V and provides a fixed output current of up to 150 mA for small to medium capacity cells.

Suitable for

• Portable electronic devices with single‑cell Li‑Ion batteries
• Battery backup modules and small UPS systems
• Custom battery pack designs requiring thermostat‑assisted charging
• Low‑power charging applications up to 150 mA

Key specifications

• Type: Li‑Ion charge controller (PMIC)
• Input voltage: 4.25–6.5 V
• Maximum charge voltage: 4.2 V
• Output (charge) current: 150 mA
• Package: SOT23-5
• Compatibility: 2YL1, 2YL2, 2YL3, 2YL4, 2YL5, 2TL6, LN5060, LTC4054, MCP73812, LTC4054ES5, С02GD

How to use

Integrate the HQ LTH7 into the charge path of a single‑cell Li‑Ion battery pack according to the device’s application schematic and pinout for SOT23-5 packages. Supply the controller with an input voltage within the 4.25–6.5 V range and connect the battery to the designated output terminal. Ensure proper thermal contact between the cell and the thermostat sensor or the PCB area used for temperature sensing so the device can adjust charging according to temperature. Observe standard Li‑Ion design practices such as cell balancing (for multi‑cell systems), proper fuse protection, and correct polarity connections.

Usage recommendations

Use the HQ LTH7 for single‑cell Li‑Ion charging applications where controlled, temperature‑dependent charge regulation is required; avoid exceeding the specified input voltage and do not rely on this single IC for full battery pack protection—combine with fusing and system‑level safety measures.