Power Bank Design Overview

2:20

Project Overview
Title: Powerbank board
Purpose:
This project is a fully-integrated bi-directional USB Power Delivery (PD) 3.0 and fast-charge power bank supporting multiple input and output ports, based on the IP5328P system-on-chip (SOC).

1. Purpose and Real-World Applications
  • Mobile Power Solution: Provides portable battery-backed power both for charging devices (phones, tablets, accessories) and possibly for powering or charging itself via USB.
  • Bi-directional Capability: Allows both charging from and supplying power to external devices using PD 3.0 and legacy USB protocols, making it compatible across a wide device ecosystem.
  • Applications: Portable chargers, smart gadgets, IoT nodes, emergency backup batteries, or DIY battery-powered hubs.

2. Core Components & Technologies

Table


ComponentType/Function
IP5328PMain Power Bank SOC: Handles USB PD, battery mgt
J1USB Micro-B: Likely for charging input
J3, J4USB Type-A outputs for charging external devices
L1Main Power Inductor for switching regulator
C1-C20, CP1-CP14Bulk and decoupling capacitors: stabilize supplies
R1-R14, RNTC1Resistors: Feedback, pull-ups, NTC for battery temp
SW1User pushbutton: on/off or function select
Q1-Q4MOSFETs: Power/power path switching & protection
D1-D8LEDs: Charging/Status indication
J2USB-C/Custom (632723100011): Possible extra port
Net Portals [+ GNDs, etc.]Board connectivity, signals, portals
Key Technologies:
  • USB Power Delivery (PD 3.0) Protocol
  • Fast charging standards
  • DC-DC switching conversion (buck-boost/etc.)
  • Smart switch/MOSFET power path control
  • Embedded microcontroller or logic within main SOC

3. Block Diagram: Major Interactions
Conceptual Block Diagram — USB PD Powerbank

Image

(Not a literal schematic, but a conceptual interaction flow)

4. Design Breakdown & Implementation Steps 4.1 Schematic Structure
  • SOC (U1) is the core, interfacing with:
    • Power input: J1 (Micro-B), J2 (Custom port)
    • Outputs: J3, J4 (Type-A)
    • Power switch/paths: Q1-Q4
    • Sensing: RNTC1 for battery temp, R1-R14 as needed for feedback/config.
    • Decoupling, filtering, and bulk capacitors keep rails and signals clean.
    • Indicator LEDs (D1-D8) provide user feedback.
4.2 Power Paths
  • Input: USB Micro-B (J1) and J2) can accept power to charge the internal battery (control via SOC and FETs).
  • Switching Regulation: L1 inductor and associated passives enable high-efficiency DC-DC conversion for stepping voltages up/down as required (boost/buck/charge).
  • Output: J3, J4 distribute power to external devices, with FETs (Q1-Q4) handling isolation and protection.
4.3 Control & Monitoring
  • User Input: SW1 allows human-initiated actions like power cycling, mode switching, or indication request.
  • Indicators: LEDs (D1-D8) show status (charging, error, power state, etc.).
  • Battery Management: Integrated NTC (RNTC1) for thermal protection, precision resistors for sensing.
4.4 Data Paths
  • USB Signals: Data and configuration lines via net portals (CC1/CC2, D+/D-, etc.) are routed to the SOC for PD negotiation, legacy USB compatibility, and charge protocol adaptation.

5. Key Design Choices, Trade-offs & Optimizations

Table


Design AspectChoice / OptimizationTrade-offs
Main SOCHigh integration (IP5328P)Simpler board, fewer support ICs; less flexibility
Power Path FETsExternal discrete MOSFETsHandles higher current, flexible protection; uses more board space
Indicator LEDsMultiple status LEDsUser clarity vs. BOM cost and routing complexity
USB PD SupportMultiple outputs, full protocolMax compatibility; adds design/test complexity
PassivesNumerous caps for stabilityReliable operation at all loads/speeds; larger BOM and more placement effort
ProtectionNTC, smart power pathsBattery safety; increased cost and tuning needed

6. Challenges & Performance Considerations
  • Thermal Design: High current paths (charging, fast-discharge) may require careful PCB thickness, copper fills, and FET selection.
  • EMI Concerns: Fast switching can produce EMI; requires good layout for inductors/caps and ground return.
  • BOM Management: Sourcing all passives at appropriate ratings (ESR/voltage/current), plus ensuring SOC/port availability.
  • Firmware/Protocol: PD negotiation must be robust and comply with standards for interoperability.

7. Scalability & Enhancement Opportunities
Areas for Improvement:
  • Add higher output current capability with beefier FETs and thicker traces.
  • Upgrade to larger battery cells and charging algorithm support.
  • Modular ports (add more Type-A/C), improve charging-discharge modes, and support wireless charging.
Future Enhancements:
  • Add microcontroller for advanced features (OLED, BLE, logging).
  • Smart monitoring (power logger, wireless interface, Bluetooth app integration).
  • Implement multi-chemistry and multi-cell balancing if scaling to larger batteries.
Layout Optimization:
  • Minimize trace lengths for switching/high-current paths.
  • Consider 4-layer PCB for improved grounding and EMI.

8. Summary Table: Main Design Elements

Table


CategoryExample PartsRole
Power ControlQ1-Q4, L1Main switching & routing
Input/Output USBJ1, J3, J4Charging and output
Main ControllerIP5328PAll power bank logic and management
MonitoringRNTC1, resistorsSafety and feedback
Status/ControlSW1, D1-D8User interface

Final Notes
This design delivers a robust, integrated, and flexible powerbank suitable for most demanding portable charging requirements. The choice of the IP5328P simplifies BOM, but demands an optimized layout and carefully-selected support components. Expandability and advanced smart features are possible with future design iterations or by integrating an auxiliary MCU.
If you need a functional block diagram, schematic review, or recommendations for layout or BOM improvements, let me know!
EMI layout guidance
Differential pair rules
Thermal simulation script
Capacitor selection
IP5328P charge spec
@copilot add an LED that indicates on green when the USB is plugged
2xip5385

0:05

C19
Capacitance
22uF
DPC
VBUSG
DPA1
VOUT2
C18
Capacitance
22uF
VBUS
DMC
CC1
VOUT2G
DMB
DMC
KEY
CP6
Capacitance
22uF
CP3
Capacitance
22uF
C3
Capacitance
100nF
C15
Capacitance
22uF
CC1
DPC
CP1
Capacitance
22uF
VBUS
DMA1
VSYS
VSYS
CP4
Capacitance
22uF
C8
Capacitance
25uF
VMID
DBP
C16
Capacitance
22uF
DPA2
C1
Capacitance
2.2uF
C17
Capacitance
22uF
CC2
VING
C6
Capacitance
100nF
DMB
C20
Capacitance
22uF
DPC
VOUT1
VMID
VIN
VIN
VING
DBP
CC2
DMA2
C5
Capacitance
22uF
VBUS
CP10
Capacitance
10uF
CP14
Capacitance
22uF
C13
Capacitance
10uF
DMC
CP2
Capacitance
22uF
C4
Capacitance
100nF
C2
Capacitance
2.2uF
VOUT1G
R5
Resistance
100 Ω
GND
VBAT+
L1
Inductance
2.2uH
R14
Resistance
120KΩ
J1
D3
D8
R7
Resistance
100 Ω
RNTC1
Resistance
100KΩ
R2
Resistance
100 Ω
C12
Capacitance
100uF
U1
Manufacturer Part Number
IP5328P
R1
Resistance
0.01 Ω
R10
Resistance
114KΩ
D4
Q4
J2
R9
Resistance
10KΩ
R12
Resistance
82KΩ
D2
D1


  • Generic Inductor
    A generic fixed inductor suitable for rapid circuit topology development. The footprint automatically adapts based on the selected package, supporting standard SMD sizes (e.g., 0402, 0603, 0805) as well as well-known inductor packages such as SDR1806, PA4320, SRN6028, and SRR1260. Standard inductor values: 1.0 nH, 10 nH, 100 nH, 1.0 µH, 10 µH, 100 µH, 1.0 mH 1.2 nH, 12 nH, 120 nH, 1.2 µH, 12 µH, 120 µH, 1.2 mH 1.5 nH, 15 nH, 150 nH, 1.5 µH, 15 µH, 150 µH, 1.5 mH 1.8 nH, 18 nH, 180 nH, 1.8 µH, 18 µH, 180 µH, 1.8 mH 2.2 nH, 22 nH, 220 nH, 2.2 µH, 22 µH, 220 µH, 2.2 mH 2.7 nH, 27 nH, 270 nH, 2.7 µH, 27 µH, 270 µH, 2.7 mH 3.3 nH, 33 nH, 330 nH, 3.3 µH, 33 µH, 330 µH, 3.3 mH 3.9 nH, 39 nH, 390 nH, 3.9 µH, 39 µH, 390 µH, 3.9 mH 4.7 nH, 47 nH, 470 nH, 4.7 µH, 47 µH, 470 µH, 4.7 mH 5.6 nH, 56 nH, 560 nH, 5.6 µH, 56 µH, 560 µH, 5.6 mH 6.8 nH, 68 nH, 680 nH, 6.8 µH, 68 µH, 680 µH, 6.8 mH 8.2 nH, 82 nH, 820 nH, 8.2 µH, 82 µH, 820 µH, 8.2 mH #generics #CommonPartsLibrary
  • Generic Capacitor
    A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF, 10pF, 100pF, 1000pF, 0.01uF, 0.1uF, 1.0uF, 10uF, 100uF, 1000uF, 10000uF 1.1pF, 11pF, 110pF, 1100pF 1.2pF, 12pF, 120pF, 1200pF 1.3pF, 13pF, 130pF, 1300pF 1.5pF, 15pF, 150pF, 1500pF, 0.015uF, 0.15uF, 1.5uF, 15uF, 150uF, 1500uF 1.6pF, 16pF, 160pF, 1600pF 1.8pF, 18pF, 180pF, 1800pF 2.0pF, 20pF, 200pF, 2000pF 2.2pF, 22pF, 220pF, 2200pF, 0.022uF, 0.22uF, 2.2uF, 22uF, 220uF, 2200uF 2.4pF, 24pF, 240pF, 2400pF 2.7pF, 27pF, 270pF, 2700pF 3.0pF, 30pF, 300pF, 3000pF 3.3pF, 33pF, 330pF, 3300pF, 0.033uF, 0.33uF, 3.3uF, 33uF, 330uF, 3300uF 3.6pF, 36pF, 360pF, 3600pF 3.9pF, 39pF, 390pF, 3900pF 4.3pF, 43pF, 430pF, 4300pF 4.7pF, 47pF, 470pF, 4700pF, 0.047uF, 0.47uF, 4.7uF, 47uF, 470uF, 4700uF 5.1pF, 51pF, 510pF, 5100pF 5.6pF, 56pF, 560pF, 5600pF 6.2pF, 62pF, 620pF, 6200pF 6.8pF, 68pF, 680pF, 6800pF, 0.068uF, 0.68uF, 6.8uF, 68uF, 680uF, 6800uF 7.5pF, 75pF, 750pF, 7500pF 8.2pF, 82pF, 820pF, 8200pF 9.1pF, 91pF, 910pF, 9100pF #generics #CommonPartsLibrary
  • Generic Resistor
    A generic fixed resistor ideal for rapid circuit topology development. Its footprint automatically adapts based on the selected package case code—supporting 0402, 0603, 0805, 1203, and many other standard SMD packages, as well as axial horizontal and vertical configurations. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0 ohm, 10 ohm, 100 ohm, 1.0k ohm, 10k ohm, 100k ohm, 1.0M ohm 1.1 ohm, 11 ohm, 110 ohm, 1.1k ohm, 11k ohm, 110k ohm, 1.1M ohm 1.2 ohm, 12 ohm, 120 ohm, 1.2k ohm, 12k ohm, 120k ohm, 1.2M ohm 1.3 ohm, 13 ohm, 130 ohm, 1.3k ohm, 13k ohm, 130k ohm, 1.3M ohm 1.5 ohm, 15 ohm, 150 ohm, 1.5k ohm, 15k ohm, 150k ohm, 1.5M ohm 1.6 ohm, 16 ohm, 160 ohm, 1.6k ohm, 16k ohm, 160k ohm, 1.6M ohm 1.8 ohm, 18 ohm, 180 ohm, 1.8K ohm, 18k ohm, 180k ohm, 1.8M ohm 2.0 ohm, 20 ohm, 200 ohm, 2.0k ohm, 20k ohm, 200k ohm, 2.0M ohm 2.2 ohm, 22 ohm, 220 ohm, 2.2k ohm, 22k ohm, 220k ohm, 2.2M ohm 2.4 ohm, 24 ohm, 240 ohm, 2.4k ohm, 24k ohm, 240k ohm, 2.4M ohm 2.7 ohm, 27 ohm, 270 ohm, 2.7k ohm, 27k ohm, 270k ohm, 2.7M ohm 3.0 ohm, 30 ohm, 300 ohm, 3.0K ohm, 30K ohm, 300K ohm, 3.0M ohm 3.3 ohm, 33 ohm, 330 ohm, 3.3k ohm, 33k ohm, 330k ohm, 3.3M ohm 3.6 ohm, 36 ohm, 360 ohm, 3.6k ohm, 36k ohm, 360k ohm, 3.6M ohm 3.9 ohm, 39 ohm, 390 ohm, 3.9k ohm, 39k ohm, 390k ohm, 3.9M ohm 4.3 ohm, 43 ohm, 430 ohm, 4.3k ohm, 43K ohm, 430K ohm, 4.3M ohm 4.7 ohm, 47 ohm, 470 ohm, 4.7k ohm, 47k ohm, 470k ohm, 4.7M ohm 5.1 ohm, 51 ohm, 510 ohm, 5.1k ohm, 51k ohm, 510k ohm, 5.1M ohm 5.6 ohm, 56 ohm, 560 ohm, 5.6k ohm, 56k ohm, 560k ohm, 5.6M ohm 6.2 ohm, 62 ohm, 620 ohm, 6.2k ohm, 62K ohm, 620K ohm, 6.2M ohm 6.8 ohm, 68 ohm, 680 ohm, 6.8k ohm, 68k ohm, 680k ohm, 6.8M ohm 7.5 ohm, 75 ohm, 750 ohm, 7.5k ohm, 75k ohm, 750k ohm, 7.5M ohm 8.2 ohm, 82 ohm, 820 ohm, 8.2k ohm, 82k ohm, 820k ohm, 8.2M ohm 9.1 ohm, 91 ohm, 910 ohm, 9.1k ohm, 91k ohm, 910k ohm, 9.1M ohm #generics #CommonPartsLibrary
  • Ground
    A common return path for electric current. Commonly known as ground.
  • Terminal
    Terminal
    An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
  • Net Portal
    Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
  • RMCF0805JT47K0
    General Purpose Thick Film Standard Power and High-Power Chip Resistor 47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film Features: - RMCF – standard power ratings - RMCP – high power ratings - Nickel barrier terminations standard - Power derating from 100% at 70ºC to zero at +155ºC - RoHS compliant, REACH compliant, and halogen free - AEC-Q200 compliant
  • 875105359001
    10 µF 16 V Aluminum - Polymer Capacitors Radial, Can - SMD 30mOhm 2000 Hrs @ 105°C #commonpartslibrary #capacitor #aluminumpolymer #radialcan
  • CTL1206FYW1T
    Yellow 595nm LED Indication - Discrete 1.7V 1206 (3216 Metric)
  • 1070TR
    Battery Holder (Open) Coin, 20.0mm 1 Cell SMD (SMT) Tab bate or batt #forLedBlink

Powerbank board

Powerbank board thumbnail
Fully-Integrated Bi-directional PD3.0 and Fast Charge Power Bank SOC with Multiple Input and Output Ports based on IP5328P

Pricing & Availability

Distributor

Qty 1

Arrow

$0.07

Digi-Key

$3.21–$5.10

HQonline

$1.09

LCSC

$7.33

Mouser

$5.59

TME

$0.58

Verical

$2.66–$3.58

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