NFC-based batteryless keyboard design
This solution implements a batteryless keyboard using Near Field Communication ( NFC ) technology. At the heart of this solution is the TI Dynamic NFC tag that can be read and written by the host microcontroller. An NFC-enabled phone can quickly discover and recognize the keyboard and then establish a connection between the keyboard and the application. The design is a battery-free system (ie, working without a battery) that can be used to build products with optimized dimensions (such as thin keyboards) and lighter weight products (such as easy to carry).
characteristic
â— No battery solution
â— Standard PC/AT keyboard character set
â— Input capability greater than 400 characters per minute
â— MSP430 MCU and RF430CL330 tags consume approximately 20 mW
â— Low cost PCB coil antenna for energy harvesting
â— Provide Android test tools and InputMethod applications
Block diagram
Batteryless Near Field Communication (NFC) Keyboard Schematic
Hardware block diagram
Battery-free near field communication (NFC) keyboard hardware block diagram
Related device
1.(TI)MSP430FR573x MSP430FR572x Mixed Signal Microcontroller
The Texas Instruments MSP430FR573x family of ultra-low-power microcontrollers consists of multiple devices featuring embedded FRAM non-volatile memory, an ultra-low-power 16-bit MSP430 CPU, and different peripherals for multiple applications. This architecture, FRAM, and peripherals, combined with seven low-power modes, is optimized for extended battery life in portable and wireless sensing applications. FRAM is a new non-volatile memory that combines the speed, flexibility, and durability of SRAM with the stability and reliability of flash memory for lower overall power consumption. The peripheral includes a 10-bit analog-to-digital converter (ADC), a 16-channel comparator with voltage reference generation and hysteresis, three enhanced serial channels supporting I2C, SPI, or UART protocol, an internal DMA, and a Hardware multiplier, a real-time clock (RTC), five 16-bit timers and digital I/O.
MSP430FR573x MSP430FR572x Mixed-Signal Microcontroller Functional Block Diagram
2.RF430CL330H Dynamic NFC Interface Repeater
The Texas Instruments Dynamic NFC Interface Transponder RF430CL330H is an NFC Tag Type 4 device that combines a wireless NFC interface with a wired SPI or I2C interface to connect this device to a host. The NDEF messages in the SRAM can be written and read by the integrated SPI or I2C serial communication interface, and this message can also be wirelessly accessed and updated via the integrated ISO14443B compatible RF interface (supporting data rates up to 848 kbps).
This enables NFC connection switching for alternate carriers, like low power (BLE), and Wi-Fi, with a simple and intuitive pairing process or authentication process with one tap. As a common NFC interface, the RF430CL330H enables end devices to communicate with the fast-growing infrastructure of NFC-enabled smartphones, tablets and laptops.
RF430CL330H Dynamic NFC Interface Repeater Functional Block Diagram
3.TPS70933 150mA, 30V Ultra Low IQ, Wide Input, Low Dropout Regulator with Reverse Current Protection
The TPS709xx family of linear regulators are ultra-low quiescent current devices designed for power sensitive applications. A precision bandgap and error amplifier has an accuracy of 2% over temperature. Only 1μA of quiescent current makes these devices an ideal solution for battery-powered normally-on systems that require minimal idle power dissipation. For added safety, these devices also feature thermal shutdown, current limiting, and reverse current protection. These regulators can be placed in shutdown mode by pulling the enable (EN) pin low. This mode has a shutdown current as low as 150nA (typical).
TPS70933 functional block diagram
The 45W MagSafe Power Adapter has a magnetic DC connector, so if someone trips on it, the power cord disconnects harmlessly, keeping your MacBook Air safe. It also helps prevent the cable from fraying or weakening over time. Additionally, the magnetic DC helps guide the plug into the system for a quick and safe connection.
45W Macbook charger air,macbook 45watt charger,45W Macbook pro charger
Shenzhen Waweis Technology Co., Ltd. , https://www.waweisasdapter.com