BQ51050B - Qi Wireless Power Receiver & Li-Ion Charger | TI
Teilenummer: BQ51050B ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $3.2 | $3,20 |
| 10 | $2.85 | $28,50 |
| 100 | $2.4 | $240,00 |
| 500 | $2.05 | $1.025,00 |
| 1.000 | $1.8 | $1.800,00 |
| 3.000 | $1.55 | $4.650,00 |
BQ51050B Übersicht
A wireless power receiver (also called a Qi Rx or wireless charging receiver IC) sits between the receiver (Rx) coil and the battery in a Qi-charged device; it captures the AC magnetic field from a Wireless Power Consortium (WPC) Qi-compliant transmitter coil, rectifies it to DC, regulates the rail, and feeds a charging algorithm to the battery. In the broader system hierarchy it belongs to power management ICs -> battery chargers -> wireless charging front-ends -> semiconductor.
Key features include WPC v1.2 communication control, programmable charge current via an external resistor, dynamic rectifier clamp that prevents over-voltage on the RX coil at light load, and integrated thermal protection with an internal thermal shutdown. The chip also provides a STAT1/STAT2 status output pair and a CHG flag for host interrogation. Availability of single-wire communication pins allows a system microcontroller to monitor charge state and fault conditions.
The BQ51050B uses a bipolar-CMOS-DMOS (BCD) process that integrates the rectifier MOSFETs directly on-die, eliminating external Schottky diodes and shrinking the BOM to the RX coil and a few passives. The output LDO cleans residual 100 kHz ripple from the synchronous rectifier, providing clean rail voltage to the system load and battery management circuit.
Typical applications include Qi-charging sleeves for smartphones, wearable fitness bands, true-wireless earbud charging cases, low-power IoT sensors, and medical patches that need to be sealed against liquid ingress. The compact 3.5x4.5 mm VQFN package is engineered for space-constrained wearable and hearable designs where every square millimeter of PCB is at a premium.
When designing with the BQ51050B, observe the layout rule that the resonant RX tank capacitor must be placed within 2 mm of the AC1/AC2 pins to minimize radiated EMI. Also note that the AD pin sense resistor sets maximum charge current; an incorrect value may cause the device to enter thermal regulation prematurely at high ambient temperatures.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes - including thermal derating guidance and EMI mitigation - not aggregated on the manufacturer datasheet homepage.
Drop-in-Alternativen für BQ51050B – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
BQ51051BRHLR
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
BQ51050BRHLR
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
BQ51050BRHLT
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
BQ51050BYFPR
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
BQ51050B Technische Daten
| Standard | Qi (WPC) v1.2 compliant |
| Topologie | Secondary-side wireless power receiver + Li-Ion/Li-Pol charger |
| Supported Battery Voltages | 4.20 V / 4.35 V / 4.40 V (orderable variants) |
| Output Voltage Options | 4.20 V / 4.35 V / 4.40 V |
| Peak AC-DC Efficiency | 93% |
| Rectifier Type | Full synchronous rectifier (on-chip N-MOSFETs) |
| Synchronous MOSFET Rdson | 100 mOhm (typical) |
| Communication Control | WPC v1.2 compliant (Qi) |
| Adjustable Charge Current | External resistor programmable |
| Integrated LDO | Yes (output rail regulator) |
| Thermisches Abschalten | Integrated |
| Status Outputs | STAT1 / STAT2 / CHG |
| Package Options | 20-VQFN (RHL, 3.5x4.5 mm) / 28-DSBGA (YFP) |
| Montageart | Surface Mount |
| RoHS-Status | Compliant |
BQ51050B Pin-Konfiguration
| Pin 1 | AC1 — AC input from receiver coil (terminal 1) |
| Pin 2 | AC2 — AC input from receiver coil (terminal 2) |
| Pin 3 | VOUT — Regulated output to battery / load |
| Pin 4 | BAT — Battery connection / charge output |
| Pin 5 | GND — Ground |
| Pin 6 | AD — Sense resistor for charge-current programming |
| Pin 7 | TS — Thermal sense / temperature flag |
| Pin 8 | STAT1 — Charge status output 1 |
| Pin 9 | STAT2 — Charge status output 2 |
| Pin 10 | CHG — Active-high charge-complete flag |
| Pin 11 | CTRL — Control pin (enable / disable) |
| Pin 12 | COM — WPC v1.2 communication interface |
| Pin 13 | RECT — Rectifier output sense / clamp |
| Pin 14 | RREF — Reference resistor |
| Pin 15 | NC — Not connected (per datasheet) |
| Pin 16 | NC — Not connected (per datasheet) |
| Pin 17 | NC — Not connected (per datasheet) |
| Pin 18 | NC — Not connected (per datasheet) |
| Pin 19 | NC — Not connected (per datasheet) |
| Pin 20 | NC — Not connected (per datasheet) |
Typische Anwendungen
BQ51050B ist geeignet für 6 Anwendungs: Qi Smartphone Charging Sleeves, True-Wireless Earbud Charging Cases, Wearable Fitness Bands, Low-Power IoT Sensor Pads, Medical Skin Patches and Continuous Monitors, Game Controllers and Portable Accessories.
Qi Smartphone Charging Sleeves
The BQ51050B fits Qi smartphone charging sleeves because its 93 percent peak AC-DC efficiency minimizes the sleeve's surface temperature rise during a 5 W charge cycle. Placed between the receiver coil and the battery management IC, the chip's integrated synchronous rectifier (100 mOhm Rdson) replaces four discrete Schottky diodes and shrinks the BOM. Compared with discrete-rectifier designs it adds integrated FOD (foreign object detection) per Qi v1.2 and provides clean 4.20 V output to a downstream charger IC. Watch the thermal envelope of the flexible PCB - the device may enter thermal regulation above 50C ambient in sealed enclosures.
Empfohlen
True-Wireless Earbud Charging Cases
True-wireless earbud cases benefit from the BQ51050B's 3.5x4.5 mm 20-VQFN footprint, which fits within typical 30 mm x 30 mm case PCBs. The chip's WPC v1.2 communication control plus STAT1/STAT2/CHG outputs let the case microcontroller report charge state via Bluetooth to the host phone. With programmable charge current up to 1.5 A the part supports both 60 mA earbud-buds trickle and 200 mA rapid case-top-up profiles without changes to the IC. The 4.35 V or 4.40 V variant is preferred for higher-energy-density Li-Po cells used in premium buds.
Empfohlen
Wearable Fitness Bands
Wearable fitness bands use the BQ51050B to provide a Qi charging interface on a sealed, water-resistant enclosure - no exposed USB port required. The integrated synchronous rectifier and LDO deliver a clean 4.20 V rail that survives the typical 100 kHz ripple common in wireless charging bursts, while the dynamic rectifier clamp prevents over-voltage when the load suddenly disconnects. The chip's small thermal footprint (3.5x4.5 mm) suits confined PCBs and the part's ability to throttle charge current on temperature rise enables safe charging under a wearable's body-heat soak.
Empfohlen
Low-Power IoT Sensor Pads
Low-power IoT sensor pads use the BQ51050B to enable contactless provisioning and battery top-up without opening hermetic seals. With WPC v1.2 communication control, the device negotiates with the Qi transmitter to draw only the 100-500 mW required by an environmental sensor, allowing indefinite operation from intermittent wireless power. The integrated LDO downstream of the synchronous rectifier delivers low-ripple DC to the sensor and microcontroller rails, eliminating the need for external filtering capacitors. Foreign object detection per Qi v1.2 protects adjacent metal structures from heating.
Empfohlen
Medical Skin Patches and Continuous Monitors
The BQ51050B suits medical skin patches by removing the exposed charging connector, which improves patient comfort and patch adhesion time. The Qi v1.2 communication ensures the device responds to certified medical-grade transmitters only, addressing hospital asset-management concerns. Integrated thermal shutdown protects the patch from overheating during long charge sessions, particularly important when the patch sits against 35C body skin. The 4.40 V variant supports high-energy-density Li-Po medical cells that store enough energy for multi-day continuous monitoring.
Empfohlen
Game Controllers and Portable Accessories
Game controllers and portable consumer accessories benefit from the BQ51050B's small footprint, which can be dropped into a Type-C-or-Qi hybrid enclosure. The chip accepts the typical 5 W Qi power budget and delivers up to 1.5 A of programmed charge current to a single-cell Li-Ion battery inside the controller handle. The integrated synchronous rectifier (100 mOhm Rdson) maintains 93 percent peak efficiency, keeping the controller's surface below 40C during a typical 90-minute charge cycle. Status outputs feed the controller's haptic / LED state engine for user feedback.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für BQ51050B – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | BQ51051BRHLR | BQ51050BRHLR | BQ51050BRHLT | BQ51050BYFPR |
|---|---|---|---|---|---|
| Package | 20-VQFN (RHL, 3.5x4.5 mm) | 20-VQFN (RHL, 3.5x4.5 mm) - same | 20-VQFN (RHL, 3.5x4.5 mm) - same | 20-VQFN (RHL, 3.5x4.5 mm) - same | 28-DSBGA (YFP) - different package, same die |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Qi Version | v1.2 compliant | v1.2 compliant | v1.2 compliant | v1.2 compliant | v1.2 compliant |
| Float Voltage | 4.20 / 4.35 / 4.40 V (orderable) | 4.10 V (lower) | 4.20 / 4.35 / 4.40 V (orderable) | 4.20 / 4.35 / 4.40 V (orderable) | 4.20 / 4.35 / 4.40 V (orderable) |
| Peak Efficiency | 93% | 93% | 93% | 93% | 93% |
| On-chip Sync Rectifier MOSFETs | Yes (100 mOhm Rdson) | Yes (100 mOhm Rdson) | Yes (100 mOhm Rdson) | Yes (100 mOhm Rdson) | Yes (100 mOhm Rdson) |
| Charge Current Adjustable | Yes (external sense resistor) | Yes (external sense resistor) | Yes (external sense resistor) | Yes (external sense resistor) | Yes (external sense resistor) |
| Automotive Grade | No | No | No | No | No |
Wichtigste Unterscheidungsmerkmale
- Single-IC integration of rectifier, LDO, and charger (vs. Discrete-rectifier + standalone charger IC designs)
- 93% peak AC-DC efficiency with on-chip synchronous rectifiers (vs. Discrete Schottky-rectifier Qi receivers)
- WPC v1.2 compliance with integrated FOD (vs. Older Qi v1.0 / v1.1 receivers)
- Three programmable float voltages from one IC family (vs. BQ51051B (4.10 V only))
Designhinweise
Place the resonant RX tank capacitor within 2 mm of the AC1/AC2 pins on the BQ51050B to minimize radiated EMI. Use a 4-layer PCB with a continuous ground plane underneath the device to provide a thermal spreading path for the synchronous rectifiers, which dissipate up to approximately 0.3 W at 5 W Qi power. Add a 4.7 uF to 10 uF X7R ceramic decoupling capacitor on VOUT close to the IC pin. Keep the RX coil traces symmetric and short - imbalance between AC1 and AC2 introduces 100 kHz ripple on the output rail.
Estimated: at 5 W Qi input and 93 percent efficiency, rectifier+LDO dissipation is approximately 0.37 W. In a sealed wearable enclosure with 50C ambient, the 3.5x4.5 mm VQFN's thermal resistance (around 50 C/W on a small 2-layer flex PCB) drives the junction to 70C, near the thermal-regulation threshold. Add thermal vias to the exposed pad and use a 4-layer rigid section under the IC where possible. Above 1 W dissipation the chip will throttle charge current, so verifying adequate copper area is critical for fast-charge in wearables.
Do not run the BQ51050B without the on-chip rectifier clamp configured for the application - leaving RREF floating causes the device to mis-detect AC amplitude and may stress the synchronous MOSFETs. Also, ensure the AD-pin sense resistor matches the desired fast-charge current; substituting 0402 size resistors with higher power rating can shift the programmed current by 10-20 percent due to temperature coefficient mismatch. Finally, the TS pin requires an external NTC for accurate thermal regulation - omitting it causes the chip to default to internal sensor and may overcharge in hot environments.
WPC Qi v1.2 communication uses 2 kHz FSK on the AC coil current, which can radiate as common-mode noise on the regulated output. Add a common-mode choke in series with the VOUT line and a ferrite bead on BAT to suppress conducted emissions below EN 55011 Class B limits. The synchronous rectifier switching edges (around 5 ns rise time) generate 100-300 MHz harmonics, so place the VOUT ceramic capacitor as close to the IC as possible and keep the loop area to the BAT pin less than 5 mm x 5 mm.
Compliance-Informationen
RoHS compliant per TI product page. The BQ51050B industrial version is not AEC-Q100 qualified - for automotive Qi applications the TI BQ51221 (or BQ51050B-Q1) should be considered. WPC v1.2 compliance certified by Qi interoperability test labs.
