TP5100 charger vs TP5000 & TP4056

TP5100 2A-switch buck 8.4V / 4.2V rechargeable lithium battery Charger || Step-down switching chip

TP5100

The TP5100 is a practical, high-efficiency lithium battery charging chip. It’s perfect for charging single-cell (4.2V) or two-cell (8.4V) lithium batteries. Its wide input voltage range, from 5V to 18V, means you can easily use common power sources like phone chargers or car adapters.

This chip offers an impressive charging current of up to 2A, adjustable simply by adding an external resistor, making it very flexible. It uses a safe three-stage charging process: trickle pre-charge, constant current fast-charge, and constant voltage top-off, ensuring batteries are charged quickly and safely.

Safety-wise, it covers all the bases—overcurrent protection, overheating protection, short-circuit protection, reverse battery protection, and even battery temperature monitoring—giving you peace of mind during charging. Its operating frequency is 400kHz, allowing the use of smaller peripheral components, saving both space and costs.

TP5100 Pinout Explanation

TP5100 Equivalent Lithium Charger

• Compatibility: Even though all these ICs share the QFN-16 package, verify that their pin assignments match your PCB layout.

• Charging Method: TP5100, TP5000, and MAX8903 use efficient buck (switching) regulators, making them suitable for applications sensitive to heat generation. In contrast, the BQ24074 employs a linear charging method, which is simpler but generates more heat at higher currents.

• Application Needs: Choose based on specific battery types, cell configurations, required charging currents, and additional features like USB input or dual power inputs.

TP5100 1S 2S Charger Circuit Diagram

Here’s a brief translation and analysis of the TP5100-based charging circuit:

1. Input Power (VIN):

• The input voltage is 12V. The TP5100 converts this voltage internally to supply a constant current and constant voltage for charging a two-cell (8.4V) lithium-ion battery.

2. TP5100 Chip Functions:

• VIN: Receives input voltage and powers the chip operation.

• LX: Connected externally to a 22µH inductor and Schottky diode, functioning as part of the high-frequency buck converter.

• BAT: Connects to the battery positive terminal, providing charge current directly.

• VS: Monitors battery voltage precisely to regulate the charging process.

• CS, R_TRICK: Set charging current (1.5A constant current, 150mA trickle charge).

• NTC (thermistor): Monitors battery temperature, protecting the battery from overheating.

3. Charging Status Indicators:

• LEDs connected to CHRG (charging) and STDBY (charging completed) pins indicate real-time charging status.

4. Protection and Filtering:

• The inductor, Schottky diode, and capacitors ensure stable output voltage and reduce high-frequency interference.

TP5100 Battery Protection Wiring

Connecting the battery protection board between the battery and TP5100:

• Connect the BAT terminal of TP5100 to the B+ terminal of the protection board.

• Connect the B- terminal of the protection board to the negative terminal of the battery.

• Connect the P- terminal of the protection board to ground (GND).