LM845 - WiFi 802.11ac + Bluetooth 4.2 USB Nano Adapter | LM Technologies
MPN: LM845 ✓ نشطLM845 نظرة عامة
A WiFi + Bluetooth USB combo dongle is a peripheral that adds short-range wireless connectivity to a host PC, embedded board, or industrial appliance via the USB bus. Inside the dongle, a single radio SoC handles both WiFi (the 802.11 family) and Bluetooth (BR/EDR/LE), sharing one antenna chain through an internal RF front-end. The host sees two logical interfaces (a network interface for WiFi and an HCI interface for Bluetooth) over USB, which simplifies driver integration and shrinks the dongle to a nano form factor that can be left plugged into a laptop or set-top box.
Key features of the LM845 include 1-stream 802.11ac Wave-2 operation with MU-MIMO, dual-band 2.4/5 GHz support, Bluetooth 4.2 Dual Mode (BR/EDR + LE) with simultaneous Classic + LE links, a USB 2.0 high-speed host interface, and a Realtek-based single-chip radio that minimizes BOM and power draw. The dongle form factor is sized for always-on installation in laptops, mini-PCs, and industrial HMIs.
The internal architecture relies on a Realtek combo MAC/baseband IC with an integrated 2.4/5 GHz PA/LNA chain. WiFi throughput reaches 433 Mbps on the 5 GHz 802.11ac 1x1 link, while Bluetooth supports the standard BR/EDR profiles plus BLE GATT services for IoT pairing and beaconing. Because WiFi and Bluetooth share the same RF chain, the firmware coordinates time-division scheduling to avoid mutual interference.
Typical applications include adding dual-band WiFi 5 + Bluetooth to legacy desktop or embedded systems, IoT gateways and industrial PCs that need a quick wireless drop-in upgrade, point-of-sale terminals that pair with BLE peripherals, retrofitted media PCs and set-top boxes that need 5 GHz WiFi for HD streaming, and developer/test rigs that require a stable Realtek-based combo radio for driver qualification.
When designing with the LM845, remember that it is a finished USB dongle, not a bare IC: designers cannot change the antenna, regulators, or USB stack. Host drivers must support the underlying Realtek chipset for full 802.11ac + Bluetooth 4.2 functionality, and the host OS USB port must provide enough bus power for the 5 GHz PA under load.
This page synthesizes verified distributor information, parametric specifications, and design guidance not consolidated on any single manufacturer or distributor page, including practical notes on host-driver compatibility and concurrent WiFi + Bluetooth operation.
بدائل مباشرة لـ LM845 — نفس الحزمة، متوافق دبوس بدبوس. تُستثنى القطع ذات الحزم المختلفة التي تتطلب تعديل PCB.
الطرازات في هذه السلسلة
طرازات من نفس السلسلة متوافقة تمامًا مع LM845 (نفس عامل الشكل والبصمة) — يختلف في Chipset, Form Factor, Host Interface, Modulation, Product Type.
LM808
✅ بديل مباشر ⚠️ مواصفات غير مُتحقق منهاتواصل لمعرفة السعر
عرض ورقة البيانات ←LM816
✅ بديل مباشر ⚠️ مواصفات غير مُتحقق منهاتواصل لمعرفة السعر
عرض ورقة البيانات ←Archer T2U Nano
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
EW-7611ULB
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
UB500
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
LM845 المواصفات (منشورة من الشركة المصنعة)
| Product Type | USB WiFi + Bluetooth combo nano adapter (dongle) |
| WiFi Standard | IEEE 802.11ac/a/b/g/n (WiFi 5, 1-stream) |
| WiFi Bands | 2.4 GHz and 5 GHz dual-band |
| MU-MIMO | Supported (Multi-User MIMO) |
| Maximum WiFi Throughput | 433 Mbps (802.11ac 1x1, 80 MHz) |
| Bluetooth Standard | Bluetooth v4.2 Dual Mode (BR/EDR + LE) |
| Bluetooth Backward Compatibility | v2.1+EDR, v3.0 |
| Concurrent Bluetooth Operation | Classic (BR/EDR) and Low Energy (LE) simultaneously |
| Host Interface | USB 2.0 (Type-A connector, nano form factor) |
| Chipset | Realtek single-chip WiFi + Bluetooth combo |
| Antenna | Internal printed/shared antenna chain (per datasheet) |
| Form Factor | Nano USB dongle |
| Power Supply | USB bus powered (5 V from host) |
| حالة RoHS | Compliant (per LM Technologies product page) |
| Compliance | IEEE 802.11ac, Bluetooth v4.2 |
LM845 الواجهات والموصلات
يكشف LM845 عن الواجهات والموصلات التالية كما نشرتها الشركة المصنعة: لاسلكي, Bluetooth. يتم تعريف توزيع أطراف رأس التوسعة وترقيم أطراف الموصل والحدود الكهربائية في وثائق الشركة المصنعة.
| لاسلكي | IEEE 802.11ac/a/b/g/n (WiFi 5, 1-stream) |
| Bluetooth | Bluetooth v4.2 Dual Mode (BR/EDR + LE) |
راجع وثائق الشركة المصنعة للحصول على مخطط توصيلات رأس التوسعة الكامل وترقيم دبابيس الموصل.
التطبيقات النموذجية
LM845 مناسب لـ 6 التطبيقs: Legacy Desktop WiFi 5 Upgrade, Industrial PC and HMI Wireless Drop-In, Point-of-Sale Terminal Bluetooth Pairing, Set-Top Box and Media PC WiFi Add-On, IoT Gateway and Developer Test Rig, Embedded Linux Single-Board Computer Wireless.
Legacy Desktop WiFi 5 Upgrade
The LM845 brings 5 GHz 802.11ac to a desktop PC that only has 10/100 Ethernet or an obsolete 2.4 GHz WiFi card. Its 433 Mbps peak throughput on a clean 5 GHz channel is more than enough for 4K streaming and large file transfers, and the nano housing leaves adjacent USB ports unobstructed. With 1-stream 802.11ac and MU-MIMO awareness, the LM845 negotiates properly with modern WiFi 5 routers without driver stack changes on Windows or Linux hosts that ship the Realtek driver for this chipset.
موصى به
Industrial PC and HMI Wireless Drop-In
Factory HMIs and industrial PCs frequently ship without 5 GHz radios or Bluetooth, and the LM845 is a clean field-upgrade path. Plug the dongle into any USB 2.0 port on the HMI, load the Realtek driver on the Linux BSP, and the device gains concurrent WiFi 5 to the plant network and BLE to nearby sensors or barcode scanners. Because the LM845 draws all power from the USB 5 V rail, no internal wiring or PSU changes are required, which simplifies retrofit installation on legacy IPCs.
موصى به
Point-of-Sale Terminal Bluetooth Pairing
POS terminals need a stable Bluetooth link to receipt printers, barcode scanners, and payment PEDs while staying on the store WiFi. The LM845's Bluetooth 4.2 Dual Mode lets the POS pair with a BLE payment terminal and a Classic Bluetooth printer simultaneously, while its 5 GHz WiFi 5 link keeps transactions flowing on a low-interference band. The nano form factor stays flush with the POS chassis and survives the constant plugging typical of retail environments.
موصى به
Set-Top Box and Media PC WiFi Add-On
Older set-top boxes, Android TV sticks, and media PCs without 5 GHz WiFi choke on HD streaming when forced onto a congested 2.4 GHz network. The LM845 upgrades them to dual-band 802.11ac with 433 Mbps of clean 5 GHz throughput, enough for multiple HD streams and over-the-top services. Its USB bus-powered design and Realtek driver support on Linux-based media player distributions make it a common drop-in accessory in this segment.
موصى به
IoT Gateway and Developer Test Rig
IoT gateways and engineering test rigs often need a known-good combo radio to validate WiFi coexistence, BLE provisioning flows, or driver bring-up. The LM845 is a popular reference design built around the Realtek 1x1 802.11ac + BT 4.2 chipset, which is the same silicon family used in many commercial gateways. Designers can plug it into a Linux dev board, validate throughput and coexistence behavior, and then port the same driver stack to a custom gateway design.
موصى به
Embedded Linux Single-Board Computer Wireless
Single-board computers like the Raspberry Pi or industrial SBCs often ship with 2.4 GHz-only radios or no radio at all, and developers need a quick path to dual-band WiFi plus Bluetooth. The LM845 plugs into any USB 2.0 host port and is recognized by mainstream Linux kernels (with the appropriate Realtek out-of-tree driver) as both a WiFi network interface and a Bluetooth HCI device. This dual personality from one dongle saves a USB port compared to using separate WiFi and Bluetooth adapters.
موصى به
ملخص المنتجات الموصى بها
بيانات مرجعية هندسية لـ LM845 — المقارنة وإرشادات التصميم ومعلومات الامتثال.
دليل الاختيار
المقارنة مع البدائل
| المعامل | هذا المنتج | LM808 | LM816 | Archer T2U Nano | EW-7611ULB | UB500 |
|---|---|---|---|---|---|---|
| Brand | LM Technologies | LM Technologies | LM Technologies | TP-Link | Edimax | TP-Link |
| Package | USB Nano Dongle | USB Nano Dongle - same | USB Nano Dongle - same | USB Nano Dongle - same | USB Nano Dongle - same | USB Nano Dongle - same |
| WiFi Standard | 802.11ac/a/b/g/n (WiFi 5) | 802.11b/g/n (WiFi 4, 2.4 GHz only) | N/A (Bluetooth-only) | 802.11ac/a/b/g/n (WiFi 5) | 802.11ac/a/b/g/n (WiFi 5) | N/A (Bluetooth-only) |
| WiFi Bands | 2.4 GHz + 5 GHz dual-band | 2.4 GHz only | N/A | 2.4 GHz + 5 GHz dual-band | 2.4 GHz + 5 GHz dual-band | N/A |
| Max WiFi Throughput | 433 Mbps (1x1 802.11ac) | 150 Mbps (1x1 802.11n) | N/A | 433 Mbps (1x1 802.11ac) | 433 Mbps (1x1 802.11ac) | N/A |
| Bluetooth | v4.2 Dual Mode (BR/EDR + LE) | None | Bluetooth (Classic) | None | Bluetooth 4.2 | Bluetooth 5.0 |
| MU-MIMO | Yes | No | N/A | No (1x1) | No (1x1) | N/A |
| Host Interface | USB 2.0 Type-A | USB 2.0 Type-A | USB 2.0 Type-A | USB 2.0 Type-A | USB 2.0 Type-A | USB 2.0 Type-A |
أبرز الفروقات
- True dual-band WiFi 5 + Bluetooth 4.2 in one nano dongle (مقابلLM808)
- MU-MIMO awareness on a 1-stream radio (مقابلArcher T2U Nano)
- Concurrent Classic Bluetooth + BLE (مقابلUB500)
ملاحظات التصميم
Estimated: The LM845 is a finished USB dongle, not a pin-compatible IC. There is no PCB-level 'drop-in' alternative at the silicon level because the antenna, regulators, and USB connector are pre-integrated into the housing. When a design seems to require a replacement, treat any alternative USB dongle as a peripheral swap and re-validate the host driver stack and regulatory certifications rather than treating it as a true IC drop-in.
Estimated: The LM845 draws all power from the host USB 5 V rail. Under 5 GHz 802.11ac transmit bursts, the dongle can pull close to the USB 2.0 high-power unit load (500 mA). If the host is a power-constrained SBC or a hub without an external supply, throughput on the 5 GHz radio can degrade during PA peaks; in that case, plug the LM845 directly into the host or use a powered hub.
Because the LM845 is a sealed nano dongle with an internal antenna, the RF environment around the USB port directly affects throughput. Plugging the dongle into a USB port on the rear of a metal PC chassis, or behind a TV, can attenuate the 5 GHz signal by 10-15 dB. Use a short USB extension cable to move the dongle into line-of-sight with the access point whenever possible.
On Linux hosts, the LM845 typically requires the out-of-tree Realtek driver (rtl88XX series) plus Bluetooth firmware files placed in /lib/firmware. Build the module against the running kernel and confirm that bluetoothd can attach the HCI device; without the firmware blob, WiFi may associate but Bluetooth will fail to enumerate. macOS support is not guaranteed for every Realtek combo chipset and should be tested before deployment.
معلومات الامتثال
RoHS compliance per LM Technologies product page. Detailed REACH, halogen-free, and conflict-minerals disclosures are not published on the public datasheet; request the full compliance statement from LM Technologies for industrial procurement.