This page covers the ELECHOUSE PN7160 NFC RFID Module — I2C Version and
PN7161 NFC RFID Module — I2C Version. The two I2C modules use the same practical host wiring style,
module connector, on-board PCB antenna structure, and I2C/NCI workflow. PN7161 adds hardware support for
Apple ECP-related reader projects, while Apple Wallet / Apple VAS authorization, certification, and application-level
software integration remain the customer’s responsibility.
Important: This documentation is for the standard I2C modules. The PN7161 MINI V1 SPI module uses a different hardware interface and should follow the PN7161 SPI documentation.
1. Quick Start
- Connect the module to the host through the 8-pin MX1.25 / JST1.25 I2C cable.
- Provide both power rails: VDD for host-interface logic and VANT for RF transmitter / antenna power. VANT may be 3.3 V or 5 V, but the software power preset must match the connected voltage.
- Use host-side I2C pull-up resistors. ELECHOUSE recommends 2.2 kΩ for both 1.8 V and 3.3 V systems.
- For Raspberry Pi / Linux, enable I2C and use the NXP
linux_libnfc-ncistack. - For ESP32 / Arduino IDE, use the ELECHOUSE PN7150 / PN7160 / PN7161 library workflow.
- Run a basic polling / tag-detection example to confirm communication and card reading.
2. PN7160 vs PN7161 I2C
| Variant | SKU | Populated IC | Apple ECP Hardware Support | Typical Use |
|---|---|---|---|---|
| PN7160 NFC RFID Module — I2C Version | NFC_PN7160_I2C | NXP PN7160A | No | Recommended default choice for Linux, Android, Raspberry Pi, ESP32, and general embedded NFC reader/writer projects where Apple ECP is not required. |
| PN7161 NFC RFID Module — I2C Version | NFC_PN7161_I2C | NXP PN7161 | Yes — hardware support only | Use when Apple ECP-related hardware support may be required. Apple Wallet / Apple VAS authorization, certification, and software integration are handled by the customer. |
3. Module Specifications
The table below lists module-level specifications and recommended operating conditions. Typical observed test results are separated in the next section.
| Parameter | Value / Recommendation |
|---|---|
| Host interface | I2C with IRQ, VEN, and DWL_REQ control pins. |
| I2C interface speed | Supports Standard-mode up to 100 kHz, Fast-mode up to 400 kHz, and High-speed mode up to 3.4 MHz. Fast-mode Plus (1 MHz) is not supported. |
| Connector / cable | Board connector: MX1.25 8P / 1.25 mm pitch vertical SMT header, 8-pin. Compatible reference: Molex PicoBlade™ 53398-0871 or equivalent. Matching cable / wire harness: JST1.25 8P / 8-pin matching housing. Compatible reference: Molex PicoBlade™ 51021-0800 or equivalent with pre-crimped terminal wires. |
| Default I2C address | 7-bit 0x28; 8-bit write/read 0x50 / 0x51. |
| I2C address range | 0x28 to 0x2B via ADR0 / ADR1 configuration. |
| ADR0 / ADR1 address setting | When 100 kΩ pulldown resistors are present, unpopulated ADRx = 0 and populated/soldered ADRx = 1. Recommended 0402 address-setting resistor: 10 kΩ, or 0 Ω jumper resistor; common for 1.8 V and 3.3 V systems. |
| I2C pull-up resistors | Recommended 2.2 kΩ pull-ups for both 1.8 V and 3.3 V logic levels. |
| VDD | Standard recommendation: 3.0–3.6 V, typ. 3.3 V. Optional 1.65–1.95 V operation, typ. 1.8 V, is supported for 1.8 V host-interface systems. |
| VDD optional 1.8 V mode | The module supports VDD(PAD) operation at 1.65–1.95 V. I2C signals (SDA/SCL), control inputs (VEN/DWL_REQ), and IRQ operate at the selected VDD logic level. Use 1.8 V I/O and 1.8 V I2C pull-ups when VDD is 1.8 V. The onboard PWR LED may be very dim or off at 1.8 V; this is normal and does not affect operation. |
| VANT | Supported RF supply modes: fixed 3.3 V or external 5 V (4.75–5.25 V for the 5 V mode). Host software must apply the matching PMU/TXLDO preset before RF configuration. |
| VANT absolute maximum | 6.0 V max recommended at module pin. |
| Operating temperature | -30°C to +85°C. |
| Storage temperature | -40°C to +85°C. Keep +85°C as the module-level limit because connector plastics, LEDs, labels, and standard assembly materials are typically rated to +85°C. |
| Operating humidity | 20% to 90% RH, non-condensing. |
| Storage humidity | 5% to 90% RH, non-condensing. Store in ESD shielding bags in a dry, temperature-controlled environment. |
| Crystal | 27.12 MHz, 3225 package, 10 pF load. |
| Antenna | On-board PCB antenna with tuned RF matching network. |
| PCB dimensions | 42.70 mm × 40.10 mm. |
| PCB thickness | 1.6 mm. |
| Mounting holes | 2 pcs, Ø 3.048 mm. |
| Compliance | CE and RoHS certified. Certificate packages and test reports are available from ELECHOUSE resources; see the download links below. |
4. Typical Observed Test Results
The following values are typical observed reference data. They are not production test limits, not guaranteed maximum ratings, and not guaranteed minimum read distances unless separately defined for a specific project.
| Item | Typical Observed Result | Condition / Limitation |
|---|---|---|
| Power consumption | See the power table below. Observed values include <2 mA in sleep/idle/polling/listen states, approx. 20 mA card-emulation active, approx. 102 mA stable active communication, approx. 114 mA peak stress read loop, and approx. 145 mA max observed active-communication peak. | Observed at VDD=3.3 V and VANT=5.0 V on test samples. Reference data only; not production test limits. |
| Read range | Typical observed values in the supplied PN7160 I2C card/tag table are approx. 5.5–14 cm depending on card/tag type. | Observed at VDD=3.3 V and VANT=5.0 V, in a metal-free environment and without metal anti-magnetic/shielding sticker. Values may vary between modules, cards/tags, orientations, and installation environments. |
5. Pinout and Wiring
5.1 Connector Pinout
The module uses an MX1.25 8P board connector. The matching cable / wire harness is JST1.25 8P.
| Pin | Signal | Direction | Description / Notes |
|---|---|---|---|
| 1 | DWL / DWL_REQ | Input | Download request / firmware mode control. 10 kΩ pulldown to GND; default low for normal boot. |
| 2 | SDA | I/O | I2C data. Host-side pull-up required. Recommended pull-up: 2.2 kΩ for both 1.8 V and 3.3 V. |
| 3 | SCL | Input | I2C clock. Host-side pull-up required. Recommended pull-up: 2.2 kΩ for both 1.8 V and 3.3 V. |
| 4 | IRQ | Output | Interrupt output to host. Logic level follows VDD(PAD). |
| 5 | VEN | Input | Enable / reset control from host. Logic level follows VDD(PAD). |
| 6 | VDD | Power | Logic / host-interface supply. Standard recommendation 3.3 V; 1.8 V operation is supported when host I/O and pull-ups also use 1.8 V. |
| 7 | GND | Power | Ground reference. |
| 8 | VANT | Power | Antenna / RF transmitter supply. Connect either a stable 3.3 V supply with the fixed-3.3V preset or a 5 V supply with the normal external-5V preset. |
5.2 Raspberry Pi I2C Wiring
| PN7160 / PN7161 I2C | Raspberry Pi 4 | Notes |
|---|---|---|
| SDA | Pin 3 / SDA | I2C data |
| SCL | Pin 5 / SCL | I2C clock |
| IRQ | Pin 16 / GPIO23 | Interrupt |
| VEN | Pin 18 / GPIO24 | Enable / reset |
| VDD | Pin 1 / 17, 3.3 V | Logic supply |
| VANT | 3.3 V mode: stable 3.3 V supply (Pi Pin 1 / 17 only if rail budget is sufficient); 5 V mode: Pin 2 / 4 | RF supply; Linux PMU/TXLDO configuration must match the selected rail |
| GND | Pin 6 / GND | Common ground |
| DWL / DWL_REQ | Pin 22 or leave default low | Optional firmware download / maintenance pin |
5.3 ESP32 I2C Wiring
| PN7160 / PN7161 I2C | ESP32 | Notes |
|---|---|---|
| DWL / DWL_REQ | GPIO19 | Optional control pin used by sample workflow |
| SDA | GPIO21 | I2C data |
| SCL | GPIO22 | I2C clock |
| IRQ | GPIO14 | Interrupt |
| VEN | GPIO13 | Enable / reset |
| VDD | 3V3 | Logic supply |
| GND | GND | Common ground |
| VANT | 3V3 (3.3 V mode) or 5V/VIN (5 V mode) | RF supply; ELECHOUSE library preset must match |
6. Power Supply Requirements
| Supply | Recommended Operating Condition | Absolute Maximum / Caution |
|---|---|---|
| VDD | 3.0–3.6 V, typ. 3.3 V for standard use. Optional 1.65–1.95 V, typ. 1.8 V, for direct connection to 1.8 V MCUs. When using 1.8 V, tie host-side I2C pull-ups to the 1.8 V rail and use 1.8 V host I/O for SDA, SCL, IRQ, VEN, and DWL_REQ. | VDD(PAD) absolute max 4.2 V per NXP. Do not drive 3.3 V GPIO into the module when VDD is 1.8 V. The onboard PWR LED may be very dim or off at 1.8 V; this is expected and does not affect chip operation. |
| VANT | Use either a stable fixed 3.3 V supply or 4.75–5.25 V (typ. 5.0 V). Apply the matching fixed-3.3V or normal external-5V software preset before RF configuration. | Recommended module absolute max 6.0 V. Do not connect 5 V to VDD, do not switch VANT while powered, and do not run a preset that does not match the connected VANT voltage. |
| GND | Common ground between module and host. | Required for all signal and power connections. |
6.1 Choose and Match the RF Supply Mode
PN7160 and PN7161 do not auto-detect VANT. The physical RF supply and host configuration must be selected as one matched pair:
| Mode | Typical 3.3 V host wiring | Arduino / ESP32 | Raspberry Pi / Linux |
|---|---|---|---|
| 3.3 V RF supply | VDD=3.3 V, VANT=3.3 V, common GND | Library source version 3.1.2, commit 10a1cb2 or later; use the fixed-3.3V preset. |
Requires a fixed-3.3V-equivalent PMU/TXLDO configuration. Arduino macros do not apply, and the copy-paste ELECHOUSE Linux procedure is still being validated; see Section 10.1. |
| 5 V RF supply | VDD=3.3 V, VANT=5 V, common GND | Use the normal external-5V preset. | Use the normal external-5V PMU/TXLDO configuration. |
Important: power down before moving VANT or changing modes. After changing mode, rebuild or reconfigure the host software, perform a full power cycle, and verify RF discovery and card reading. Current published power and read-range tables were measured at VDD=3.3 V and VANT=5 V and are not claims of identical 3.3 V performance.
6.2 Typical Observed Power Consumption
| Operating State | Typical Observed Current Consumption (reference only; not production test limit) |
|---|---|
| Sleep / Idle / Polling / Card emulation listen | < 2 mA |
| Card emulation active | approx. 20 mA |
| Active card communication, stable | approx. 102 mA |
| Peak stress read loop, typical observed | approx. 114 mA |
| Active card communication, max observed peak in test sample | approx. 145 mA |
7. I2C Interface and Addressing
- Default 7-bit I2C address: 0x28.
- 8-bit write/read addresses at default setting: 0x50 / 0x51.
- Supported I2C bus modes: Standard-mode up to 100 kHz, Fast-mode up to 400 kHz, and High-speed mode up to 3.4 MHz.
- Fast-mode Plus (1 MHz) is not supported.
- Host-side SDA/SCL pull-ups are required; recommended value is 2.2 kΩ.
- Pull-up voltage must match the selected VDD logic level.
7.1 Power-up, Reset, and Control Pins
| Item | Requirement / Behavior |
|---|---|
| Hardware reset via VEN | Hold VEN low for ≥10 µs to reset the module. |
| Boot-up delay | After pulling VEN high with stable VANT and VDD, wait at least 2.5 ms before initiating the first I2C communication. |
| IRQ behavior | IRQ is an active-high digital output. It rises to the VDD logic level when NCI data is pending and returns low after the host reads the data packet over I2C. |
| Normal boot | Keep DWL_REQ low during boot. The module’s onboard 10 kΩ pulldown keeps DWL_REQ low by default. |
| Firmware download boot | Pull DWL_REQ high before pulling VEN high. DWL_REQ high level is referenced to the VDD logic level. |
8. NFC / RF Capabilities
| Item | Description |
|---|---|
| Operating frequency | 13.56 MHz NFC / RFID band. |
| Supported modes | Reader/Writer, Peer-to-Peer, Card Emulation. |
| Protocols / technologies | ISO/IEC 14443A/B, ISO/IEC 15693, FeliCa, MIFARE, NFC Forum Type 1–5 tags. Final supported features may depend on host software stack and integration. |
| Antenna | On-board PCB antenna with tuned matching network. |
| PN7160 / PN7161 RF performance | The two I2C module versions use the same module RF front-end and antenna layout, so read-range performance is expected to be similar. If PN7161 read range is critical, validate using PN7161 samples in the final installation. |
| Apple ECP / Apple Wallet / Apple VAS | PN7161 provides hardware support related to Apple ECP reader projects. Apple Wallet / Apple VAS authorization, certification, and application-level software integration remain the customer’s responsibility. |
8.1 Read Range Test Data
The following table is transcribed from ELECHOUSE supplied PN7160 I2C read-range test data. Test condition: VANT=5 V, VDD=3.3 V, no surrounding metal, and no metal anti-magnetic/shielding sticker. Values are typical observed reference results only; they are not production test limits and not guaranteed minimum read distances.
| Tag / Model | Standard | Protocol | Chip / Variant | Size (cm) | Typical Observed Read Range (cm) not guaranteed minimum |
|---|---|---|---|---|---|
| NFC Type 1 Tag | ISO 14443A | T1T (0x1) | Topaz 512 | 8.5 × 5.4 | 10.5 |
| NFC Type 2 Tag | ISO 14443A | T2T (0x2) | MIFARE Ultralight C | 8.5 × 5.4 | 5.5 |
| NFC Type 2 Tag (Ultralight AES) | ISO 14443A | T2T (0x2) | Ultralight AES | 8.5 × 5.4 | 10.5 |
| NFC Type 2 Tag (Ultralight EV1) | ISO 14443A | T2T (0x2) | Ultralight EV1 | 8.5 × 5.4 | 10.5 |
| NFC Type 2 Tag (NTAG213) | ISO 14443A | T2T (0x2) | NTAG213 | 8.5 × 5.4 | 10.4 |
| NFC Type 2 Tag (NTAG215) | ISO 14443A | T2T (0x2) | NTAG215 | 8.5 × 5.4 | 10 |
| NFC Type 2 Tag (NTAG216) | ISO 14443A | T2T (0x2) | NTAG216 | 8.5 × 5.4 | 10.5 |
| NFC Type 3 Tag | ISO 14443A | T3T / FeliCa (0x3) | FeliCa Lite-S RC-S966 | 8.5 × 5.4 | 9 |
| NFC Type 4 Tag (DESFire 8K) | ISO 14443A | ISO-DEP / Type 4 (0x4) | MIFARE DESFire 8K | 8.5 × 5.4 | 7 |
| NFC Type 4 Tag (NTAG424 DNA) | ISO 14443A | ISO-DEP / Type 4 (0x4) | NTAG424 DNA | 8.5 × 5.4 | 10.7 |
| NFC Type 4 Tag | ISO 14443B | ISO-DEP / Type 4 (0x4) | — | 8.5 × 5.4 | 6.5 |
| NFC Type 5 Tag | ISO 15693 | ISO15693 / NFC-V (0x6) | ICODE SLS | 8.5 × 5.4 | 14 |
| NFC Type 5 Tag (ICODE SLIX2) | ISO 15693 | ISO15693 / NFC-V (0x6) | ICODE SLIX2 | 8.5 × 5.4 | 14 |
| NFC Type 5 Tag (ICODE SLIX) | ISO 15693 | ISO15693 / NFC-V (0x6) | ICODE SLIX | 8.5 × 5.4 | 14 |
| MIFARE One S70 | ISO 14443A | — | MIFARE One S70 | 8.5 × 5.4 | 10.5 |
| MIFARE One S70 compatible card | ISO 14443A | — | MIFARE One S70 compatible card | 8.5 × 5.4 | 8.5 |
| NFC Type 4 Tag | ISO 14443A | ISO-DEP / Type 4 (0x4) | MIFARE DESFire EV1 2K | 8.5 × 5.4 | 7.3 |
9. Installation Environment and Antenna Guidelines
9.1 Metal Clearance
| Condition | Recommendation / Expected Effect |
|---|---|
| Metal behind read-card area, distance ≥50 mm | Recommended best-performance installation distance. At this distance, metal has little effect on antenna parameters. |
| Metal behind read-card area, distance <50 mm | If operation at this distance is unavoidable, add a ferrite absorber sheet between the module/read-card area and the metal to reduce antenna detuning. Typical ferrite absorber sheet specification: thickness 0.1–0.3 mm; real permeability μ′ recommended 60–150 at 13.56 MHz. |
9.2 Cable Routing Guidelines
- Preferred routing: Route the connection cable straight away from the connector and keep it completely outside the PCB antenna boundary / active card-reading zone.
- If crossover is unavoidable: Route the cable harness perpendicular (90°) to the nearest on-board antenna trace to minimize magnetic coupling.
- Critical warning: Do not route cables in a closed loop or bundle excess wire within the active card-reading zone. A closed loop of wire can behave as a shorted turn, absorbing the 13.56 MHz RF field and drastically reducing read range.
9.3 Card-Specific Matching / Custom Tuning Service
For projects that require best performance with a fixed card/tag type, ELECHOUSE can provide card-specific debugging and matching/tuning as a customization service. This is normally only needed when the application environment is demanding, such as close metal, constrained installation space, strict read-distance requirements, or harsh RF conditions.
10. Software Setup
10.1 Raspberry Pi / Linux
- Enable I2C in
raspi-configand verify that/dev/i2c-1exists. - Install prerequisites such as
autoconf,automake,libtool, andgit. - Clone NXP
linux_libnfc-nciand use the PN7160 / NCI 2.0 configuration flow. - Set
NXP_TRANSPORT=0x02andNXP_NFC_DEV_NODE="/dev/i2c-1"inlibnfc-nxp.conf. - Select PMU/TXLDO settings that match the actual 3.3 V or 5 V VANT rail, then build, install, fully power-cycle, and test with
nfcDemoApp poll.
# Raspberry Pi / Linux quick test
sudo raspi-config
# Enable I2C
ls /dev/i2c*
git clone https://github.com/NXPNFCLinux/linux_libnfc-nci.git -b NCI2.0_PN7160
cd linux_libnfc-nci
./bootstrap
./configure
make
sudo make install
export LD_LIBRARY_PATH=/usr/local/lib
nfcDemoApp pollLinux power configuration: setPn7160FixedVbat3V3() and PN71XX_FIXED_VBAT_3V3 belong to the ELECHOUSE Arduino library and do not configure NXP’s Linux stack. For 3.3 V VANT, the Linux middleware must use the equivalent fixed-3.3V PMU/TXLDO configuration and disable any voltage check that is not applicable to that supply path. For 5 V VANT, retain the normal external-5V configuration.
The byte layout of NXP_EXT_TVDD_CFG, NXP_EXT_TVDD_CFG_1, and NXP_EXT_TVDD_CFG_2 depends on the NXP middleware version. A copy-paste ELECHOUSE 3.3 V Linux configuration is still being validated; do not reuse Arduino preset bytes in libnfc-nxp.conf. Until the exact module and middleware combination has been validated, use a known-good 5 V Linux configuration or contact ELECHOUSE support. Any 3.3 V candidate must be checked for RF field start, tag reading, and cold boot on the target board.
10.2 ESP32 / Arduino IDE
- Install ELECHOUSE library source version 3.1.2, commit
10a1cb2or later from ELECHOUSE_PN7150_PN7160. - Wire VDD, VANT, and GND according to one of the two power modes above.
- Before including
Electroniccats_PN71xx_ExampleTransport.h, setPN71XX_USE_SPI 0and select the matchingPN71XX_FIXED_VBAT_3V3value. - Build and upload the example, then verify tag detection after a complete power cycle.
| I2C mode | Required definitions |
|---|---|
| VANT=3.3 V | #define PN71XX_USE_SPI 0#define PN71XX_FIXED_VBAT_3V3 1 |
| VANT=5 V | #define PN71XX_USE_SPI 0#define PN71XX_FIXED_VBAT_3V3 0 |
The shared I2C examples default PN71XX_FIXED_VBAT_3V3 to 0, so 3.3 V VANT users must enable it explicitly. These shared-example macros take effect through pn71xxConfigureExampleTransport(nfc); a custom sketch that does not use the helper must call the setter directly.
In a custom I2C sketch, explicitly select PN7160 in the constructor; the shorter three-argument constructor defaults to PN7150 and will not use the PN7160/PN7161 power path:
Electroniccats_PN7150 nfc(IRQ_PIN, VEN_PIN, 0x28, PN7160);For manual initialization, use this order: connectNCI() → setPn7160FixedVbat3V3(true) for 3.3 V or false for 5 V → configureSettings() → configMode() → startDiscovery(). The setter selects a preset; configureSettings() is what writes the selected configuration. If an application uses a begin() path that performs connection and configuration internally, select the power preset before calling begin().
11. Troubleshooting
| Symptom | Possible Cause / Check |
|---|---|
| No I2C response | Verify SDA/SCL wiring, GND, VEN, IRQ, VDD, VANT, and the selected I2C address. |
| Linux stack starts but no tags detected | Check NXP_TRANSPORT, NXP_NFC_DEV_NODE, IRQ/VEN wiring, and that the NXP PMU/TXLDO configuration matches the actual 3.3 V or 5 V VANT rail. |
| ESP32 sketch uploads but no tag read | Confirm pin definitions and both power rails. If NCI communication works but no RF field or tag is detected, check for a 3.3 V / 5 V VANT preset mismatch. |
| Read range is shorter than expected | Check for nearby metal, cable loops, card/tag type, card orientation, enclosure design, ferrite absorber sheet placement, and VANT supply stability. |
| Wrong I2C address | Check ADR0 / ADR1 resistor configuration and ensure the host uses the matching 7-bit address. |
Power-guidance update (2026-08-28): this web page reflects the dual-supply support in ELECHOUSE library 3.1.2. Until the linked PDFs are revised, a PDF that shows VANT=5 V only documents the existing 5 V mode; use this page for the current 3.3 V library configuration.
12. Official Downloads and Resources
13. Related Pages
- PN7160 vs PN7161 — when do you need Apple ECP?
- RFID & NFC Module Selection Guide
- PN7161 MINI V1 — SPI product page
14. Power and Test Reference Notes
- 3.3 V VANT support requires a matching fixed-3.3V PMU/TXLDO preset; it is not a wiring-only change.
- 5 V VANT remains fully supported with the normal external-5V preset.
- Published read-range and power-consumption values remain identified as VANT=5 V test data.
- For Linux, use configuration values that match the installed NXP middleware and verify them on the target hardware.
15. Update History
- 2026-08-28: Added software-matched 3.3 V and 5 V RF supply modes for Arduino/ESP32 and separate Linux PMU/TXLDO guidance; retained all VANT=5 V performance test conditions.
- 2026-06-24: Unified PN7160 / PN7161 I2C documentation page created from the existing PN7160/PN7161 docs and the formal PN716x datasheet V1.0 content.