Download the IP5189T circuit diagram for China power banks. Explore detailed schematics to aid in your electronic repairs and project developments.
The IP5189T is an integrated power management IC designed specifically for power bank applications. It combines several functions into a single chip, making it a popular choice for compact, efficient designs. It handles tasks such as battery charging, power conversion, and providing status indications through LEDs. Its versatility and feature set allow it to efficiently manage lithium-ion or lithium-polymer batteries, ensuring safe operation and maximum battery life.
Key Functional Blocks and Connections
1. Power Input Ports
Micro-B (VIN and GND): The left side of the circuit shows a standard Micro-USB connector for input power.
VIN: Connects to the power input pin of the IP5189T to supply power.
GND: Connects to the ground pin of the IC.
Type-A (VOUT and GND): On the same side, a USB Type-A connector allows for output.
VOUT: This supplies 5V output to charge external devices.
2. IP5189T Pinout Explanation
VIN: Input power pin connected to the Micro-B connector, providing the circuit with power.
VOUT: Outputs 5V through the USB Type-A port for device charging.
DM/DP: USB data lines for communication, typically to negotiate fast-charging protocols.
ICHG: A current sense pin that controls charging current.
PGND/AGND: Ground connections for power and analogue sections.
LX: Switching node connected to an inductor (1µH). It participates in the DC-DC conversion process.
VBAT: Battery connection pin for monitoring and charging the battery pack.
VTHS: Voltage threshold pin, used to set or monitor battery status.
NTC: A connection for a thermistor, monitoring battery temperature for safe charging.
LIGHT: Drives indicator LEDs to show the battery level or charging status.
KEY: Input for a button to control or toggle charging modes or LED indicators.
RSET: Sets the charging current via an external resistor.
VSET: A pin to adjust the output voltage based on the needs of the application.
3. Output LEDs and Battery Indicator
L1, L2, L3: Three LEDs connected in parallel. They light up based on the charge state, controlled by the IP5189T through resistors.
RSET and KEY: These components allow the user to set the brightness of the LEDs and toggle states via a button press.
4. Battery Management Section
VBAT Pin: Connected to a lithium-ion or lithium-polymer battery.
NTC: A thermistor connected to monitor battery temperature and ensure safe operation.
1 µH Inductor: Works as part of a buck-boost converter to regulate voltage.
Key Features of the IP5189T
Before diving into the schematic details, let’s explore some of the IP5189T's standout features:
Integrated Buck-Boost Converter: Ensures a stable 5V output regardless of battery voltage.
Battery Charging Management: Supports various charging profiles with safety features like temperature monitoring.
LED Indicators: Drives multiple LEDs to indicate charging status or battery level.
USB Data Line Management: Provides basic USB communication for fast-charging protocols.
Thermal Protection: Monitors battery temperature through an NTC thermistor.
Compact Design: Reduces the required external components, saving space and cost.
Schematic Overview and Key Components
Your circuit diagram includes the IP5189T chip surrounded by various external components. Let’s break it down section by section, explaining each component’s role.
1. Power Input Section
The power input section allows the user to charge the power bank’s internal battery. The circuit supports two types of input:
Micro-USB (Type B Connector):
VIN: The input voltage is supplied through the Micro-USB port.
GND: Ground connection ensures a common reference for the circuit.
The input voltage from the Micro-USB connector typically ranges from 4.5V to 5.5V, which is standard for USB power sources.
2. USB Output Section
The USB output section allows the power bank to charge external devices:
Type-A USB Port:
VOUT: Provides a stable 5V output for charging external devices.
GND: Common ground connection.
The VOUT pin of the IP5189T regulates the output voltage using a buck-boost converter, ensuring a stable 5V output even if the battery voltage fluctuates.
3. IP5189T Pin Descriptions and Functions
Here’s a detailed explanation of each pin on the IP5189T and its function:
VIN: This pin receives the input voltage from the Micro-USB connector. It powers the internal circuitry and charges the battery.
VOUT: The output voltage pin, regulated to 5V, powers the USB output port.
DM/DP: These are the USB data lines. They play a role in fast-charging protocols by communicating with connected devices and adjusting power output accordingly.
ICHG: This pin controls the charging current. An external resistor connected to this pin sets the maximum charging current.
PGND/AGND: Power ground and analogue ground pins provide the reference for different sections of the chip, ensuring stable operation.
LX: This pin connects to an external inductor (1 µH in this circuit). It is part of the buck-boost converter, which steps up or down the voltage as needed.
VBAT: The battery connection pin monitors the battery voltage and manages charging/discharging.
VTHS: Voltage threshold pin. It helps in setting limits for the battery voltage during charging and discharging.
NTC: This pin connects to a thermistor (NTC) to monitor battery temperature. If the temperature exceeds safe limits, the chip reduces or stops charging to protect the battery.
LIGHT: This pin drives the status LEDs. The chip can light up one or more LEDs to indicate charging progress or battery level.
KEY: A button or switch connected to this pin allows users to toggle charging modes or check battery status by activating the LEDs.
RSET: A resistor connected to this pin sets the charging current. By selecting an appropriate resistor value, designers can control how fast the battery charges.
VSET: This pin allows fine-tuning of the output voltage, ensuring compatibility with various devices.
4. Inductor and Power Conversion
A 1 µH inductor is connected to the LX pin. This inductor is crucial for the buck-boost conversion process:
Buck-Boost Converter: The IP5189T can both step up (boost) and step down (buck) the input voltage to maintain a constant 5V output. This ensures devices receive a stable voltage regardless of the battery’s charge level.
5. Battery Management and Safety Features
Battery management is a critical aspect of any power bank circuit. The IP5189T includes several safety features:
Battery Connection (VBAT): The lithium-ion battery connects to the VBAT pin. The chip monitors the battery voltage and controls charging accordingly.
Temperature Monitoring (NTC): The thermistor (connected to the NTC pin) ensures the battery is charged within a safe temperature range. If the battery gets too hot, charging is slowed down or stopped to prevent damage.
Voltage Threshold (VTHS): This pin sets the maximum and minimum voltage thresholds for the battery, ensuring it is not overcharged or deeply discharged.
6. LED Indicators
The circuit includes three LEDs (L1, L2, L3), driven by the LIGHT pin:
LED Status Indication: The IP5189T can light up one or more LEDs to indicate the battery’s charge level or charging status. The LEDs are connected through current-limiting resistors to ensure safe operation.
7. User Control (KEY Pin)
A button connected to the KEY pin allows the user to interact with the power bank:
Toggle LED Status: Pressing the button can toggle the LEDs to show the battery level or charging status.
Mode Switching: In some designs, the button may also switch between different power modes (e.g., normal charging, fast charging).
Component Selection and Considerations
When designing a power bank circuit around the IP5189T, careful component selection is essential:
Inductor (1 µH): Choose an inductor with a suitable current rating to handle the maximum load.
Resistors: Select resistors for current limiting (LEDs) and setting the charging current (RSET).
Thermistor: Use an NTC thermistor with appropriate resistance and temperature characteristics.
Capacitors: Place decoupling capacitors near the VIN and VOUT pins to stabilize the voltage and reduce noise.
Working Principle of the Circuit
Power Input and Regulation:
The circuit receives power through the Micro-USB port. The VIN pin feeds this power to the IP5189T, which regulates it.
Battery Charging:
The chip monitors the battery voltage and temperature, charging it safely. The ICHG and RSET pins control the charging current.
Power Output:
The buck-boost converter ensures a stable 5V output, regardless of battery voltage.
User Feedback and Control:
The button (KEY pin) allows users to check battery status, and the LEDs provide visual feedback on charge levels.
Applications of the IP5189T Circuit
This circuit can be used in:
Portable Power Banks: To charge smartphones, tablets, and other gadgets.
USB Chargers: For charging multiple devices simultaneously.
DIY Projects: For hobbyists building custom power banks.