CP2104-MINIEK - USB-to-UART Bridge Mini Dev Kit | Silicon Labs
MPN: CP2104-MINIEK ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.96 | $5.96 |
| 10 | $5.96 | $59.60 |
| 25 | $5.96 | $149.00 |
| 100 | $5.36 | $536.00 |
| 250 | $4.76 | $1,190.00 |
CP2104-MINIEK Overview
A USB-to-UART bridge is a class of interface IC that translates between the USB protocol used by a host PC and the asynchronous serial (UART) protocol used by microcontrollers, MCUs, and legacy devices. Bridges such as the CP2104 belong to the broader family of interface ICs (USB interface controllers) which sit between the host computer and the target embedded system, replacing legacy DB-9 RS-232 ports that modern laptops no longer provide. The CP2104 in particular integrates the USB transceiver, clock generation, and 3.3 V LDO on-chip, eliminating the need for an external crystal, external USB pull-ups, and a separate regulator - significantly simplifying PCB layout for space-constrained designs.
Key features of the CP2104 silicon include USB 2.0 full-speed (12 Mbps) compliance, integrated 3.3 V LDO regulator with output current up to 100 mA for external circuitry, internal 48 MHz oscillator eliminating the need for an external crystal, support for data formats of 5, 6, 7, 8 data bits; 1, 1.5, 2 stop bits; and odd/even/mark/space/no parity, and royalty-free Virtual COM Port (VCP) drivers for Windows, macOS, and Linux kernels. The device also provides four configurable GPIO pins accessible via the host driver, allowing designers to toggle LEDs, sense buttons, or control peripheral resets without adding extra MCU I/O.
From an architectural standpoint, the CP2104 leverages a hardened USB SIE (Serial Interface Engine) with on-chip transceivers that meet USB 2.0 full-speed PHY requirements, plus an embedded 8051-compatible microcontroller core that handles USB enumeration, descriptor handling, and UART framing. The integrated one-time programmable ROM lets OEMs customize USB VID, PID, product string, and default baud-rate settings at production time, while the UART engine supports hardware flow control (RTS/CTS) and XON/XOFF software flow control for reliable high-speed communication with industrial MCUs and DSPs.
Typical applications include industrial control modules, point-of-sale terminals, medical instrumentation data ports, USB dongles for firmware updates on wireless sensor nodes, robotics debug interfaces, and any embedded design that needs a PC connection without an on-board USB-capable MCU. The CP2104-MINIEK kit accelerates such designs by providing a working USB-to-UART bridge with all pins broken out to standard 0.1-inch headers, allowing direct connection to target boards.
When designing with the CP2104, engineers should observe USB-IF signal-integrity guidelines: keep the D+/D- traces as a 90-ohm differential pair with no stubs, place the VBUS decoupling capacitor within 2 mm of the VBUS pin, and use the internal 3.3 V LDO only for low-current support circuitry (under 100 mA) to avoid thermal stress on the small QFN-24 package.
This page synthesizes the manufacturer's datasheet, distributor pricing as of 2026-10-22, drop-in pin-compatible alternatives, and practical design notes not found on distributor product pages.
Drop-in alternatives for CP2104-MINIEK — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with CP2104-MINIEK (same form factor and footprint) — differing in Operating Temperature, Function, Package, Product Type, Supply Voltage (VCC).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
CP2104-EK
✅ Drop-In📋 Reference alternative (not in catalog)
CP2102N-MINIEK
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
CP2102N-DK
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
CH9102F
✅ Drop-In📋 Reference alternative (not in catalog)
CH340G
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$0.31 / Unit
View Datasheet →FT232RL-REEL
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.55 / Unit
View Datasheet →CP2104-MINIEK Specifications (manufacturer-published)
| Product Type | USB-to-UART Bridge Mini Evaluation Kit |
| Base IC | CP2104 |
| Function | USB 2.0 to UART Bridge |
| USB Compliance | USB 2.0 Full-Speed (12 Mbps) |
| UART Data Rates | 300 bps to 2 Mbps |
| IC Package | QFN-24 (4x4 mm) |
| Integrated Features | USB transceiver, internal oscillator, 3.3 V LDO, OTP ROM |
| Supply Voltage (VBUS) | 5 V from USB |
| Integrated LDO Output | 3.3 V, up to 100 mA |
| GPIO | 4 configurable GPIO pins |
| Modem Control Signals | RTS, CTS, DTR, DSR, DCD, RI |
| Data Bits | 5, 6, 7, 8 |
| Stop Bits | 1, 1.5, 2 |
| Parity | None, Odd, Even, Mark, Space |
| Flow Control | Hardware (RTS/CTS) and Software (XON/XOFF) |
| Operating Temperature | -40C to +85C |
| RoHS Status | Compliant |
CP2104-MINIEK Pin Configuration
| Pin 1 | DCD — Data Carrier Detect (input, active low) |
| Pin 2 | RI — Ring Indicator (input, active low) |
| Pin 3 | DSR — Data Set Ready (input, active low) |
| Pin 4 | DTR — Data Terminal Ready (output, active low) |
| Pin 5 | CTS — Clear To Send (input, active low) |
| Pin 6 | RTS — Request To Send (output, active low) |
| Pin 7 | RXD — UART Receive Data (input to CP2104) |
| Pin 8 | TXD — UART Transmit Data (output from CP2104) |
| Pin 9 | VBUS — USB VBUS input (5 V from host) |
| Pin 10 | GND — Ground |
| Pin 11 | D+ — USB Data Plus |
| Pin 12 | D- — USB Data Minus |
| Pin 13 | VDD — 3.3 V regulated output (from internal LDO) |
| Pin 14 | REGIN — Voltage regulator input |
| Pin 15 | RESETb — Active-low reset (tie to VDD for normal operation) |
| Pin 16 | GPIO0 — General-purpose I/O 0 |
| Pin 17 | GPIO1 — General-purpose I/O 1 |
| Pin 18 | GPIO2 — General-purpose I/O 2 |
| Pin 19 | GPIO3 — General-purpose I/O 3 |
| Pin 20 | NC — Not connected (per datasheet) |
| Pin 21 | NC — Not connected (per datasheet) |
| Pin 22 | NC — Not connected (per datasheet) |
| Pin 23 | NC — Not connected (per datasheet) |
| Pin 24 | EPAD — Exposed thermal pad; tie to GND for thermal relief |
Power & Thermal Characteristics
| Power Input | 5 V from USB |
| Operating Temperature | -40C to +85C |
Power input and thermal parameters for CP2104-MINIEK as published by the manufacturer.
Typical Applications
CP2104-MINIEK is suitable for 7 applications: Industrial Control Module USB Interface, Point-of-Sale Terminal Data Upload, Embedded MCU Firmware Development Bridge, Medical Instrumentation Data Port, USB Dongle for Wireless Sensor Network Gateway, Robotics Debug and Programming Interface, Education and Maker-Focused USB-to-UART Learning Kit.
Industrial Control Module USB Interface
The CP2104-MINIEK evaluation kit accelerates prototype development of industrial control modules that need USB connectivity to a host PC for configuration upload, firmware update, and runtime diagnostics. The CP2104's integrated 3.3 V LDO eliminates the need for an external regulator in the target design, while its 2 Mbps maximum UART rate supports high-speed fieldbus data logging via Modbus-RTU or similar serial protocols. Place the kit between a host laptop and a target MCU board via UART handshake lines; the CP2104's hardware RTS/CTS flow control handles industrial-grade burst traffic without overrun, and four configurable GPIO pins let engineers toggle industrial relays or read button states directly from the host driver.
Recommended
Point-of-Sale Terminal Data Upload
The CP2104-MINIEK provides the host-side USB link for point-of-sale terminals that push transaction logs, receipt image metadata, or inventory syncs to a back-office PC. The CP2104's on-chip oscillator and integrated voltage regulator reduce POS enclosure BOM cost by removing the external crystal and LDO, while its USB 2.0 full-speed compliance ensures USB-IF interoperability with retail docking cradles. Use it during development to validate the UART framing for fiscal printer interfaces (often 9600/19200/115200 baud with odd parity) and to certify the driver stack across Windows POS-Ready and Linux-based POS distros.
Recommended
Embedded MCU Firmware Development Bridge
The CP2104-MINIEK is the canonical bench tool for engineers flashing and debugging custom firmware on MCUs that lack native USB, such as the ATmega128A or STM32F4 series in legacy boards. With UART data rates up to 2 Mbps, the CP2104 supports fast bootloader protocols (STM32 system memory boot, AVR ISP-via-UART, ESP8266/ESP32 firmware upload) without becoming the throughput bottleneck. Engineers connect the kit's TX/RX/3V3/GND lines to the target MCU's UART header, leaving the CP2104-MINIEK's four GPIO free for use as reset-and-boot strap signals via the host driver API.
Recommended
Medical Instrumentation Data Port
Medical device prototypes use the CP2104-MINIEK to evaluate USB-to-UART data acquisition channels for patient-monitoring peripherals, blood-analyzer modules, and portable ultrasound probes. The CP2104's wide -40C to +85C operating range supports clinical environments, while its integrated electrostatic-discharge protection on D+/D- lines (per USB compliance) reduces accessory BOM. During development the kit exposes the full UART handshake set so designers can validate hardware flow control for continuous waveform streaming at 921600 baud.
Recommended
USB Dongle for Wireless Sensor Network Gateway
IoT gateway prototypes use the CP2104-MINIEK as the host-side bridge into a wireless sensor network hub built around Sub-GHz radios, BLE modules, or LoRa transceivers. The CP2104's four GPIs let the gateway software toggle radio reset lines, drive TX-enable pins, and read interrupt flags directly through the VCP driver API, avoiding an extra MCU just for pin control. With the on-chip 3.3 V LDO supplying up to 100 mA, the kit can power low-current sensor frontend boards during bench bring-up without a separate bench supply.
Recommended
Robotics Debug and Programming Interface
Robotics engineers use the CP2104-MINIEK as a compact debug bridge between a host PC and robot controllers, motor-driver boards, and sensor-fusion IMUs that expose UART debug headers. The kit's small form factor suits cramped robot enclosures during bench testing, and the 2 Mbps UART rate allows fast firmware flashing for time-critical robotics middleware. Connect TX/RX to the controller's primary UART, route RTS/CTS to the motor-driver enable lines, and reserve two GPIO channels for emergency-stop and watchdog-reset control via host script.
Recommended
Education and Maker-Focused USB-to-UART Learning Kit
The CP2104-MINIEK is used in university embedded-systems courses and maker workshops to teach USB protocol fundamentals, driver installation, and serial-port programming. Because the VCP drivers are royalty-free across Windows, macOS, and Linux, students install once and switch operating systems without licensing concerns. The kit's four GPIOs are ideal for lab exercises in bit-banging peripherals (LEDs, pushbuttons, simple SPI slaves) from host-side C/Python code via the Silicon Labs library, accelerating project demos.
Recommended
Recommended Products Summary
Engineering reference data for CP2104-MINIEK — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | CP2104-EK | CP2102N-MINIEK | CH9102F | CH340G | FT232RL |
|---|---|---|---|---|---|---|
| Brand | Silicon Labs | Silicon Labs | Silicon Labs | WCH | WCH | FTDI |
| Package | QFN-24 (4x4 mm) on mini EK board | QFN-24 (4x4 mm) on full-size EK board | QFN-28 (5x5 mm) on mini EK board | QFN-24 (4x4 mm) | SOP-16 | SSOP-28 |
| USB Compliance | USB 2.0 Full-Speed (12 Mbps) | USB 2.0 Full-Speed (12 Mbps) | USB 2.0 High-Speed (480 Mbps) | USB 2.0 Full-Speed (12 Mbps) | USB 2.0 Full-Speed (12 Mbps) | USB 2.0 Full-Speed (12 Mbps) |
| Maximum UART Baud Rate | 2 Mbps | 2 Mbps | 3 Mbps | 3 Mbps | 2 Mbps | 3 Mbps |
| Integrated 3.3 V LDO | Yes (up to 100 mA) | Yes (up to 100 mA) | Yes | Yes | No (requires external 3.3 V) | Yes (internal 3.3 V LDO) |
| Internal Oscillator | Yes (no external crystal) | Yes (no external crystal) | Yes | Yes | Yes (12 MHz internal) | Yes (12 MHz internal, clock-out pin) |
| Modem Control Lines | Full set (RTS/CTS/DTR/DSR/DCD/RI) | Full set | Full set | Full set | Limited (TX/RX only in default mode) | Full set |
| Driver Model | Silicon Labs VCP (royalty-free Windows/macOS/Linux) | Silicon Labs VCP | Silicon Labs VCP | WCH VCP (royalty-free) | WCH VCP (royalty-free) | FTDI D2XX / VCP |
Key Differentiators
- Compact QFN-24 (4x4 mm) with full modem-control line set (vs FT232RL (SSOP-28))
- Integrated 3.3 V LDO with up to 100 mA drive (vs CH340G (SOP-16, no integrated LDO))
- Four configurable GPIO pins accessible via VCP driver API (vs CH340G (0 GPIO))
- Royalty-free VCP drivers for Windows, macOS, and Linux (vs FT232RL (FTDI VCP drivers))
- Integrated USB transceiver and 48 MHz oscillator (vs Discrete USB-to-UART implementations)
Design Notes
Route the USB D+ and D- traces as a 90-ohm differential pair with no stubs and matched length within 150 mil. Keep the trace length under 50 mm total when possible to stay within USB 2.0 full-speed signal-integrity margins. Place the CP2104's VBUS decoupling capacitor (typically 4.7 uF) within 2 mm of the VBUS pin to suppress inrush transients during host enumeration. The exposed thermal pad (EPAD) on the QFN-24 must be soldered to a ground copper pour with at least 4 thermal vias for heat dissipation.
The CP2104's internal 3.3 V LDO can deliver up to 100 mA to external circuitry. Do not exceed this limit, or the LDO will enter thermal shutdown on the small QFN-24 package. For designs needing more 3.3 V current, disable the internal LDO and use an external regulator tied to VBUS. The VBUS pin must see 5 V from the host; undervoltage triggers a USB detach event that drops the VCP port on the host.
Do not leave unused GPIO pins floating - they can draw extra current and cause spurious interrupts. Tie unused GPIOs to VDD or GND through 10 kohm resistors. When designing the UART side, ensure voltage compatibility: the CP2104's UART is 3.3 V CMOS-logic-level; connecting directly to a 5 V MCU UART may exceed absolute-maximum ratings. Use a level translator (such as a resistor divider or dedicated IC like MAX3232 for RS-232) if the target operates at a different logic level.
Estimated: With the CP2104 in USB 2.0 full-speed mode, the upstream cable and connector losses typically add 1.5 to 3 dB at 12 MHz; combined with the device's own jitter budget, this leaves only 4-5 dB margin from the USB-IF compliance template. To stay compliant, keep the D+/D- pair matched to 90 ohms +/- 10%, avoid sharp bends, and isolate the USB differential pair from any switching signals (such as the CP2104's own UART at high baud rates) by at least 3 trace widths. EMI from the CP2104's internal oscillator may couple into adjacent traces if not properly ground-walled.
Estimated: The CP2104's QFN-24 package has a theta-JA of approximately 50 C/W on a 2-layer JEDEC-standard test board. When the internal 3.3 V LDO delivers the full 100 mA to external load, internal dissipation is roughly 170 mW (5 V minus 3.3 V at 100 mA). Junction temperature rise over ambient is therefore approximately 8.5 C above 25 C ambient, well below the 125 C maximum. If the application places the CP2104 in a sealed enclosure with no airflow, derate LDO current to 60 mA or provide additional copper pour under the EPAD to spread heat.
Compliance Information
RoHS and REACH compliance confirmed via Silicon Labs product documentation for the CP2104 silicon. AEC-Q100 not applicable for commercial-grade evaluation kit. Lead-free assembly and packaging per Silicon Labs environmental compliance statement. Halogen-free status not explicitly stated in retrieved data.
