TP4056 — 1A Standalone Linear Li-Ion / LiPo Battery Charger IC

Overview

The TP4056 is a 1.0 Amp standalone linear Lithium-Ion and Lithium-Polymer (LiPo) battery charger IC manufactured by NanJing Top Power. Sold worldwide as a cheap $1\text{cm} \times 2\text{cm}$ red or blue breakout module with Micro-USB or USB-C connectors (and frequently paired with a DW01A battery protection IC and FS8205A dual MOSFET for over-charge, over-discharge, and short-circuit protection), it safely charges single-cell $3.7\text{V}$ Li-Ion / 18650 / LiPo cells to a target voltage of $4.20\text{V}$ .

Operating on a standard $5.0\text{V}$ USB power supply, the TP4056 implements a complete Constant-Current / Constant-Voltage (CC/CV) charging profile with programmable charge current (up to $1.0\text{A}$ ), thermal regulation, automatic recharge, and dual open-drain LED status outputs (/CHRG and /STDBY).

Quick reference


Charger Type	Constant-Current / Constant-Voltage (CC/CV) Linear Charger
Package	8-pin SOP-8 with exposed bottom thermal pad / Breakout Board
Input Supply Voltage (`VCC`)	4.0 V to 8.0 V DC (5.0 V USB nominal)
Final Float Charge Voltage	$4.20\text{ V}$ DC ( $\pm 1.5\%$ accuracy)
Max Programmable Charge Current	$1.0\text{ A}$ ( $1000\text{ mA}$ , set by $R_{PROG}$ resistor)
Precharge Trickle Threshold	$2.9\text{ V}$ (Trickle charge at $10\%$ current for deeply discharged cells)
Charge Status Indicators	Red LED (`/CHRG` pin 7) = Charging / Blue or Green LED (`/STDBY` pin 6) = Fully Charged
Battery Protection Pair	DW01A protection IC + FS8205A dual N-MOSFET (on protected modules)

Pinout (SOP-8 Package & Module Terminals)

text

             ┌───┴───┐
        TEMP ─┤ 1   8 ├─ VCC
        PROG ─┤ 2   7 ├─ /CHRG
         GND ─┤ 3   6 ├─ /STDBY
         BAT ─┤ 4   5 ├─ CE
             └───────┘

Module Pin Label	Name	Type	Description
`IN+` / `USB`	`VCC`	Power	Positive $5.0\text{V}$ DC power input from USB
`IN-`	`GND`	Power	Ground reference (0 V)
`BAT+` / `B+`	`BAT`	Battery Connection	Connects to positive lead of 3.7V Li-Ion / LiPo battery
`BAT-` / `B-`	`GND` / `Protection`	Battery Connection	Connects to negative lead of battery (via DW01A MOSFET on protected boards)
`OUT+`	`OUT+`	Load Power Output	Regulated load output (+) on protected module boards
`OUT-`	`OUT-`	Load Power Output	Load output ground (-) (cuts off at 2.4V battery protection threshold)

Specifications

Parameter	Symbol	Min	Typ	Max	Unit	Conditions
Input Supply Voltage	$V_{CC}$	4.0	5.0	8.0	V	USB 5.0V input
Regulated Output Voltage	$V_{BAT}$	4.137	4.200	4.263	V	$0^\circ\text{C} \le T_A \le 85^\circ\text{C}$
Charge Current ( $R_{PROG}=1.2\text{k}\Omega$ )	$I_{BAT}$	900	1000	1050	mA	RPROG = 1200 Ω
Trickle Charge Threshold	$V_{TRIKL}$	2.8	2.9	3.0	V	$V_{BAT}$ rising
C/10 Termination Current	$I_{TERM}$	—	0.1	—	$\times I_{BAT}$	Charge cycle termination threshold
Shutdown Supply Current	$I_{MSD}$	—	55	100	µA	$V_{CC}$ disconnected

Charge Current Programming ( $R_{PROG}$ Resistor Table)

The continuous charge current ( $I_{BAT}$ ) is programmed by resistor $R_{PROG}$ connected between Pin 2 (PROG) and GND:

$I_{BAT}\text{ (mA)} = \frac{1200\text{V}}{R_{PROG}\text{ (k}\Omega\text{)}} \times 1000$

$R_{PROG}$ Resistor Value	Programmed Charge Current ( $I_{BAT}$ )	Recommended Battery Capacity
$1.2\ \text{k}\Omega$ (Default on modules)	$1000\text{ mA}$ ( $1.0\text{A}$ )	$\ge 1000\text{ mAh}$ (e.g. 18650 cell)
$1.66\ \text{k}\Omega$	$700\text{ mA}$	$\ge 700\text{ mAh}$
$2.4\ \text{k}\Omega$	$500\text{ mA}$	$\ge 500\text{ mAh}$
$5.0\ \text{k}\Omega$	$250\text{ mA}$	$\ge 250\text{ mAh}$
$10.0\ \text{k}\Omega$	$130\text{ mA}$	$\ge 130\text{ mAh}$ (small LiPo cells)

CC/CV Charging Profile Stages

text

 Voltage (V) / Current (A)
   4.2V  ─────────────────────────────┐ (Constant Voltage Stage)
         │                           │ ╲
         │   (Constant Current)      │  ╲  Current Drops
   2.9V ─┼───────────────────────────┤   ╲  to C/10
   (0.1A)│---(Trickle Precharge)---- │    └── Charge Complete (STDBY LED ON)
   0V    └───────────────────────────┴─────────────────────── Time

Trickle Precharge: If battery voltage $< 2.9\text{V}$ , the charger outputs $10\%$ of programmed current ( $100\text{ mA}$ ) to safely recover deeply discharged cells.
Constant Current (CC): Once $V_{BAT} \ge 2.9\text{V}$ , full programmed current ( $1.0\text{A}$ ) is delivered to the battery while voltage rises toward $4.20\text{V}$ .
Constant Voltage (CV): When $V_{BAT}$ reaches $4.20\text{V}$ , voltage is held constant while charge current decays.
Charge Termination: When current drops to $C/10$ ( $100\text{ mA}$ ), charging terminates, the red LED turns OFF, and the blue/green LED turns ON.

Wiring (Protected TP4056 Breakout Module)

TP4056 Module Pin	Power Source / Battery / Load	Notes
`IN+` / `USB`	+5V USB Power Supply	Charge power input
`IN-`	USB GND	Charge ground
`B+`	Li-Ion / 18650 Battery (+)	Battery positive lead
`B-`	Li-Ion / 18650 Battery (-)	Battery negative lead
`OUT+`	MCU / System Load 5V/3.3V LDO	Load power positive output
`OUT-`	MCU System Ground	Load power ground output

Common mistakes

Charging small LiPo batteries (<500mAh) at the default 1A rate: Default TP4056 modules come pre-soldered with a $1.2\ \text{k}\Omega$ $R_{PROG}$ resistor ( $1.0\text{A}$ charge rate). Charging small $100\text{ mAh}$ or $250\text{ mAh}$ LiPo cells at $1.0\text{A}$ ( $4C \dots 10C$ rate) causes severe overheating and fire hazards. Desolder the $1.2\text{k}$ resistor and replace it with a $5\text{k}\Omega$ or $10\text{k}\Omega$ resistor for small LiPo cells.
Connecting battery in reverse polarity: Connecting battery + to B- and - to B+ instantly destroys the TP4056 IC.

Notes

TP4056 vs MCP73831 vs BQ24160: TP4056 is a low-cost 1A linear charger; MCP73831 is Microchip's 500mA linear charger; BQ24160 is a TI switch-mode charger.

Interface	Dual LED Charge Status Outputs (CHRG, STDBY), PROG Current Programming
Package	8-pin SOP-8 (Thermal Pad) / Micro-USB & USB-C Charger Breakout Board