Classic CC2430 hardware application circuit

RF card terminal selected as TI's CC2430 RF chip, which is Chipcon company's first in line 802.15.14 / Zigbee technology RF system-on-chip. ZigBee or the like for a variety of ZigBee wireless network nodes, including a tuner, routers and end devices. It has a very significant low cost, and low power consumption, multi-node network, transmission distance and other advantages, has the following main features: integrated in line with IEEE802.15.4 standard RF transceiver; excellent wireless receiver sensitivity and strong anti-jamming ; hardware support CSMA / CA function; digital RSSI / LQI support.

　　CC2430 hardware application circuit is shown below, given the radio frequency terminals of each employee are required to wear one, from a cost savings perspective, to take a simple classic design approach, using an unbalanced antenna circuit, connecting unbalanced Transformer enables better antenna performance.

　　

　　Figure 1 CC2430 application circuit diagram

　　Balun circuit by the capacitor C341 and inductors L341, L321, L331, and a microwave transmission line consisting of PCB, the entire structure to meet the RF input / output matching resistors (50Ω) requirements. Internal T / R switching circuit to complete the exchange between LNA and PA. R221 and R261 for the bias resistors, resistor R221 is mainly used to provide a suitable operating current of 32 MHz crystal. Using a 32 MHz quartz resonator (XTAL1) and two capacitors (C191 and C211) constitute a 32MHz crystal oscillator circuit. Constitute a 32.768 kHz crystal oscillator circuit with a 32.768 kHz quartz resonators (XTAL2) and two capacitors (C441 and C431). Voltage regulator for all requirements and internal 1.8V voltage supply pin, C241 and C421 capacitive decoupling capacitors are used to supply filtered to improve the stability of the chip work.