Gym & 24/7 Fitness Club Access Control Hardware
Gym access control system hardware for 24/7 clubs: fob and wristband readers, face and QR terminals, anti-passback controllers and no-touch exit buttons.
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LF-140 Mini 125 kHz EM RFID Module with Wiegand and UART Output
24.3 × 16 × 11.8 mm, 2.1 g low-frequency module with an external antenna that reads EM4100-family credentials at 0–8 cm and reports over Wiegand or 5 V UART.
- Reads EM4100, EM4102, EM4200, EM4305 and EM4450 credentials at 0–8 cm
- 24.3 × 16 × 11.8 mm board (antenna excluded), about 2.1 g
- Wiegand and UART communication at 5 V logic; UART at 9600 baud
- External LF antenna that can be shaped to fit your enclosure
- ≤ 80 mA reading and ≤ 50 mA standby from a 5 V DC supply
- Frequency
- 125 kHz
- Credentials
- EM4100/4102/4200/4305/4450
- Read range
- 0–8 cm
- Output
- Wiegand and UART, 5 V (UART 9600 baud)
- Power
- 5 V DC, ≤ 80 mA
- Dimensions
- 24.3 × 16 × 11.8 mm (excl. antenna)
Reply within 24 hours Tested before dispatch Worldwide shipping
Mini 125 kHz EM RFID Module with Wiegand and UART Output: overview
The LF-140 is a mini 125 kHz RFID module for engineers adding card or fob identification to compact electronics such as handheld devices, tablets, keyboards, displays, self-service terminals and fare-collection equipment. The board measures 24.3 × 16 × 11.8 mm without its antenna and weighs about 2.1 g, so it drops into housings that cannot take a conventional reader module.
It reads EM4100, EM4102, EM4200, EM4305 and EM4450 credentials at 0–8 cm, depending on the tag and the installation. Budget up to 80 mA from the 5 V rail while it reads and up to 50 mA in standby.
Because the LF antenna is external, you can shape it around your product: a coil behind a front bezel, around a display window or inside a keypad. Antenna size and placement affect range, so validate the final geometry in production-intent enclosures.
Integration notes
The module runs from 5 V DC and supports both Wiegand and UART communication at 5 V logic, with the UART at 9600 baud. Operating range is –20 to +70 °C (–4 to +158 °F) at 20–80% RH non-condensing, and storage is rated –40 to +80 °C. No product certification is listed for the module, so plan compliance testing at the finished-device level.
More features
- Operates from –20 to +70 °C, 20–80% RH non-condensing
LF-140 specifications
RF & credentials
| Frequency | 125 kHz |
|---|---|
| Supported credentials | EM4100, EM4102, EM4200, EM4305, EM4450 |
| Read distance | 0–8 cm (depends on installation and credential) |
| Antenna | External LF antenna |
Interfaces
| Communication | Wiegand and UART (5 V logic) |
|---|---|
| UART baud rate | 9600 |
Electrical
| Supply voltage | 5 V DC |
|---|---|
| Operating current | ≤ 80 mA |
| Standby current | ≤ 50 mA |
Mechanical & environment
| Dimensions | 24.3 × 16 × 11.8 mm ±0.5 mm (excluding antenna) |
|---|---|
| Weight | Approx. 2.1 g |
| Operating temperature | –20 to +70 °C (–4 to +158 °F) |
| Operating humidity | 20–80% RH, non-condensing |
| Storage temperature | –40 to +80 °C (–40 to +176 °F) |
| Certification | None listed for the module |
Specifications can change between production batches. Confirm the current revision with us before placing volume orders.
Ordering options
Quote the SKU that matches your frequency, interface and mounting. Not sure? Send us your controller model and we will pick the variant for you.
| SKU | Configuration | Actions |
|---|---|---|
| LF-140-E-W-T | Mini 125 kHz EM module, Wiegand and 5 V UART (9600 baud), external LF antenna |
Where the LF-140 is used
- Handheld terminals that log EM4100 key fobs or tool tags in the field
- Keyboards, displays or kiosks that sign in operators with a badge
- Self-service and fare-collection terminals with very little internal space
- Locker keypads that accept a 125 kHz member fob alongside a PIN
RFID Asset & Tool Tracking
Build an RFID asset tracking system: on-metal, ceramic and tie-on tags matched to each asset, handheld audits, smart cabinets and IP67 HF heads for tooling.
LF-140 FAQ
Which 125 kHz chips can the LF-140 read?
EM4100, EM4102, EM4200, EM4305 and EM4450 credentials, plus cards and fobs compatible with them.
What read range should I plan for?
Between 0 and 8 cm. The result depends on your antenna, the credential and nearby materials, so measure it in the finished housing.
What UART settings does it use?
The UART runs at 9600 baud with 5 V logic levels. Wiegand output is also supported on the same module.
Does the module carry CE or FCC certification?
No certification is listed for this module. Treat it as a component and cover it in the compliance testing of your finished product.
Can the antenna be designed around my enclosure?
Yes. The antenna sits off the board, so its coil size and placement can be adapted to your housing; send your mechanical constraints with the RFQ and we will confirm an antenna option.
Before you buy
Related buyer guides
Wiegand vs OSDP vs RS485: Which Reader Interface Should You Specify?
Compare Wiegand, OSDP and RS485 reader interfaces: wiring, cable limits, AES-128 Secure Channel and steps for a compatible access-control migration.
125kHz vs 13.56MHz: Choosing Access Cards and Readers
125 kHz cards are cheap but easy to clone; 13.56 MHz cards add memory and, on DESFire-class chips, AES security. Compare range, chips, security and migration.
Wiegand 26-Bit Format Explained (with a Free Calculator)
Wiegand 26-bit is an even parity bit, 8-bit facility code, 16-bit card number and odd parity bit. Convert card numbers to hex and back with the calculator.
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Get pricing for the LF-140
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