CP2101-GMR - USB 2.0 to UART Bridge | Silicon Labs
MPN: CP2101-GMR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.1063 | $4.11 |
| 10 | $3.95 | $39.50 |
| 100 | $3.5 | $350.00 |
| 500 | $3.1 | $1,550.00 |
| 1,000 | $2.8 | $2,800.00 |
CP2101-GMR Overview
A USB-to-UART bridge is an interface IC that translates USB host traffic into a conventional UART serial stream, allowing legacy serial equipment, embedded controllers, and service ports to communicate through a USB connector. The CP2101 belongs to the USB interface-controller and interface-IC hierarchy, where USB signaling, UART conversion, clocking, and device identification are consolidated into one controller. Its integrated USB transceiver removes the need for external USB transceiver resistors, while its integrated clock eliminates the need for an external crystal in supported configurations.
The CP2101-GMR provides 28 QFN pins and includes an integrated 512-byte EEPROM according to the verified distributor and technical search data. The device is identified as a USB-to-UART controller for USB applications and is available in a lead-free, RoHS-compatible package designation. The search data identifies the CP2101 as a mature product that is not recommended for new designs, while the CP2102 is described as a pin- and software-compatible alternative recommended for new designs.
Typical uses include USB-to-RS-232 adapters, embedded development systems, industrial equipment, instrumentation, and legacy serial-port upgrades. Designers should evaluate the CP2102 family for new products when appropriate because the verified CP2101 data sheet material identifies CP2101 as mature and points engineers to CP2102 for new designs. Existing CP2101-GMR boards can use the device when its supply, package, driver, and interface requirements remain unchanged.
Layout should preserve the exposed-pad thermal and electrical requirements of the 28-QFN package, route USB differential pairs with controlled impedance, and follow the manufacturer’s recommended decoupling and grounding arrangement. For a replacement decision, verify the exact package, pinout, USB power configuration, UART voltage levels, and host-driver behavior rather than relying only on the USB-to-UART function.
Drop-in alternatives for CP2101-GMR — 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 CP2101-GMR (same form factor and footprint) — differing in Package, Product Type, RoHS Status, UART Interface, Supply Voltage.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
CP2102-GMR
✅ Drop-In✓ In Stock
$1.4897 / Unit
View Datasheet →CP2102N-A01-GQFN28R
✅ Drop-In✓ In Stock
$2.31 / Unit
View Datasheet →CP2103-GMR
✅ Drop-In✓ In Stock
Contact for price
View Datasheet →CP2101-GM
✅ Drop-In✓ In Stock
$5.77834 / Unit
View Datasheet →CP2102C-A01-GQFN28
✅ Drop-In📋 Reference alternative (not in catalog)
CP2101-GMR Specifications
| Product Type | USB-to-UART bridge controller |
| USB Interface | USB 2.0 |
| Supply Voltage | 3 V to 3.6 V |
| Package | 28-QFN (5 x 5 mm) |
| Pin Count | 28 pins |
| Mounting Type | Surface mount |
| Integrated USB Transceiver | Yes |
| External USB Transceiver Resistors | No external resistors required |
| Integrated Clock | Yes |
| External Crystal | No external crystal required |
| Integrated EEPROM | 512 byte |
| UART Interface | RS-232 UART signals |
| Lead-Free Status | Lead free |
| RoHS Status | RoHS status reported as compliant in search data |
| DigiKey Listing | In stock listing shown as ships today |
| LCSC Price Reference | $4.1063 as shown in search result |
CP2101-GMR 28-qfn (5 x 5 mm) Pin Configuration Guide
Pin configuration for CP2101-GMR (28-qfn (5 x 5 mm) package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for CP2101-GMR.
Refer to the datasheet for full pin configuration.
Typical Applications
CP2101-GMR is suitable for 6 applications: USB-to-RS-232 Adapter, Embedded Development Boards, Industrial Serial-to-USB Conversion, Test and Measurement Equipment, Legacy Equipment USB Upgrade, Instrumentation and Data Acquisition.
USB-to-RS-232 Adapter
CP2101-GMR is suitable for replacing a conventional serial interface in an RS-232 adapter because the verified data identifies it as a USB-to-UART bridge supporting RS-232 UART signals. Its integrated USB transceiver and integrated clock reduce the number of external components and simplify the transition from an RS-232 connector to USB. The 3 V to 3.6 V supply range should be checked against the adapter’s power architecture. Before production, verify the complete pinout, USB power configuration, UART logic levels, and host-driver support in the manufacturer data sheet.
Recommended
Embedded Development Boards
CP2101-GMR can provide a compact USB console connection for embedded development boards that expose a UART debug or programming interface. The USB 2.0 interface, integrated transceiver, and integrated clock make it a practical bridge between a host computer and an embedded controller. The 28-QFN 5 x 5 mm package supports compact layouts, although the exposed pad and USB routing must follow the manufacturer’s guidance. Firmware and host software should be tested for the exact operating system, baud rate, and USB enumeration behavior.
Recommended
Industrial Serial-to-USB Conversion
CP2101-GMR can be used in industrial equipment that needs to expose an existing UART through USB for configuration, diagnostics, or service access. The bridge consolidates USB and UART functions into one interface IC, while the verified integrated clock and USB transceiver reduce external support circuitry. Industrial suitability must be confirmed because the supplied data does not state the operating-temperature range, isolation rating, EMC class, or lifecycle commitment. Use the final electrical limits and application guidance before deploying it in safety- or production-critical equipment.
Recommended
Test and Measurement Equipment
CP2101-GMR is applicable to test and measurement instruments that need a compact computer-to-instrument serial connection. Its USB-to-UART conversion allows legacy control protocols to be retained while the external connector changes to USB. The verified 28-QFN package and integrated USB transceiver can help reduce board area, but the complete pinout and operating limits are not included in the supplied search data. Designers should verify isolation, grounding, ESD protection, cable behavior, and host-driver support according to the instrument’s safety requirements.
Recommended
Legacy Equipment USB Upgrade
CP2101-GMR can modernize legacy serial equipment by adding USB connectivity without redesigning the equipment’s existing UART-based control protocol. The verified data describes the device as a highly integrated USB-to-UART bridge intended to update RS-232 designs using minimal components and PCB space. This makes it useful for service ports, configuration interfaces, and legacy peripherals. The replacement should be evaluated against the original system’s voltage levels, handshake signals, baud rates, and software drivers; those complete requirements are not supplied in the verified snippets.
Recommended
Instrumentation and Data Acquisition
CP2101-GMR can serve as the host interface in compact instrumentation or data-acquisition equipment that communicates through a UART command protocol. The USB 2.0 bridge provides a modern connector while preserving the simple serial interface used by the embedded measurement controller. The integrated transceiver and clock simplify the USB-side implementation, while the 28-QFN footprint helps control board size. Verify the instrument’s isolation strategy, UART electrical levels, timing requirements, and driver compatibility before production; the supplied data does not confirm those application-specific limits.
Recommended
Recommended Products Summary
Engineering reference data for CP2101-GMR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | CP2102-GMR | CP2102N | CP2103-GMR | CP2101-GM | CP2102C-A01-GQFN28 |
|---|---|---|---|---|---|---|
| Brand | Silicon Labs | Silicon Labs | Silicon Labs | Silicon Labs | Silicon Labs | Silicon Labs |
| Package | 28-QFN 5 x 5 mm | 28-QFN, exact suffix details need verification | 28-QFN, exact suffix details need verification | 28-QFN | 28-QFN, exact suffix details need verification | 28-QFN |
| Interface | USB 2.0 to UART | USB-to-UART, details need verification | USB-to-UART, details need verification | USB-to-UART | USB-to-UART, details need verification | USB-to-UART |
| Design Recommendation | Mature product; CP2102 identified as recommended for new designs | Recommended alternative family for new designs | Replacement and upgrade family identified in porting documentation | Related CP210x USB-to-UART family | CP2101-family comparison part | Pin-compatible CP2102C variant with USB-pin divider consideration |
Key Differentiators
- Mature CP2101 USB-to-UART platform with established CP210x ecosystem (vs CP2102-GMR)
- Integrated USB transceiver reduces external USB support circuitry (vs CP2102C-A01-GQFN28)
- Integrated clock avoids an external crystal (vs CP2102-GMR)
- Compact 28-QFN package for space-constrained serial bridges (vs CP2102N)
Design Notes
Use the manufacturer’s 28-QFN land pattern and exposed-pad recommendations rather than constructing the footprint from the package dimensions alone. Keep USB D+ and D+ routing as a controlled-impedance differential pair, minimize stubs, and place USB connector ESD protection close to the connector. The verified search results identify the package as 28-QFN 5 x 5 mm, but the complete pinout and land pattern were not supplied.
Design the 3 V to 3.6 V supply path and local decoupling around the CP2101-GMR according to the manufacturer’s recommended schematic. USB-powered and self-powered systems must be treated as separate implementation cases because the verified porting-guide result specifically mentions a voltage-divider arrangement for CP2102C USB pins. Confirm the actual USB power architecture before copying a reference design.
Do not assume that every CP2102 or CP210x-family ordering code is a direct drop-in replacement for CP2101-GMR. The verified data supports compatibility at a family or porting-guide level, but the exact suffix, package, USB power configuration, exposed pad, driver, and UART behavior must be checked. For new designs, the verified CP2101 documentation recommends evaluating CP2102 because CP2101 is described as mature and not recommended for new designs.
Keep the USB interface electrically and physically separated from sensitive analog or high-current paths where practical. Provide a continuous ground reference beneath the USB region, follow the recommended USB trace geometry, and verify differential impedance with the actual board stack-up. The integrated transceiver can simplify the circuit, but it does not eliminate connector, routing, ESD, or grounding design requirements.
Compliance Information
The verified technical-search data reports RoHS compliance and lead-free status. It does not provide verified REACH, AEC-Q100, halogen-free, or conflict-minerals information. The supplied data also does not establish an automotive qualification.
