参数资料
型号: SX1223SK915
厂商: Semtech
文件页数: 7/25页
文件大小: 0K
描述: KIT STARTER FOR XE1223 915MHZ
产品培训模块: SX1223 ISM Transmitter
标准包装: 1
类型: 发射器,UHF
频率: 915MHz
适用于相关产品: XE1223(915MHz)
已供物品: 2 个板,2 个模块,2 根天线,线缆,文档
产品目录页面: 584 (CN2011-ZH PDF)
SX1223
4
GENERAL DESCRIPTION
The SX1223 is a 2-level FSK transmitter. The circuit operates in one of two frequency ranges, 425 to 475 MHz, and
850 to 950 MHz, allowing the 3 main ISM frequency bands (434 MHz, 869 MHz and 915 MHz) to be addressed by
the circuit. It is capable of operating at data rates between 1.2 and 153.6 kbit/s, making it ideally suited for
applications where high data rates are required.
The SX1223 is a highly programmable device – channel, bit rate, frequency deviation and output power – which
makes it extremely flexible to meet a large number of end user requirements.
The main functional blocks of the SX1223 are the frequency synthesizer, the modulator, the power amplifier (PA),
the voltage regulators and some additional service blocks. The device also includes a set of configuration registers
and a digital interface. In a typical application, the SX1223 is programmed by a microcontroller via the 3-wire serial
bus SI, SO, SCK to write to and read from the internal registers.
The Frequency Synthesizer generates the carrier (the local oscillator (LO) signal).
The Modulator performs the modulation of the carrier by the input bit stream.
The Power Amplifier amplifies the modulated RF signal to the antenna port.
The Voltage Regulators generate regulated supply voltages for the different parts of the chip, and allow battery
voltages up to 3.6 V to be used.
The Service Blocks provide the internal voltage and current sources and provide all the necessary functions for the
circuit to work properly.
The Configuration Registers are a set of registers that are used to store various settings to operate the SX1223
transmitter circuit. Please refer to Section 5.2 for the detailed descriptions of these registers. These registers are
accessed in write or read mode through the 3-wire serial bus, as described in Section 5.1.
The Digital Interface provides internal control signals for the whole circuit according to the configuration register
settings.
4.1
FREQUENCY SYNTHESIZER
4.1.1 General Structure
The frequency synthesizer is an integer-N PLL and consists of a voltage-controlled oscillator (VCO), a crystal
oscillator, a prescaler, programmable frequency dividers and a phase-detector. The loop-filter is external for
flexibility and can be a simple passive circuit. The lengths of the M and N and A counters are respectively 12, 12
and 6 bits.
To enable the prescaler Prescal_s register (address 16, bit 4) has to be written to 1. The M, N and A values can be
calculated from the formula:
where
f XCO :
f RF :
FreqBand:
f RF =
Crystal oscillator frequency
RF frequency
0: RF frequency 425-475 MHz
f XCO
M ? ( 2 ? FreqBand )
( 16 ? N + A )
1: RF frequency 850-950 MHz
M is the divide factor applied to the reference frequency, N and A are the counters of the frequency divider in the
feedback loop of the PLL.
There are two sets of each of these divide factors (M0, N0, A0 and M1, N1, A1). In modulation modes mw1 and
mw2 (register bit Modulation1=0), only the M0, N0 and A0 are used to fix the carrier frequency. If modulation by
using the dividers is selected (mw3, Modulation1=1, Modulation0=0), the two sets are used to program the two RF
? Semtech 2007
7
www.semtech.com
相关PDF资料
PDF描述
TC50V6A32K7680 OSCILLATOR 32.7680 KHZ 1.5V SMD
TC70V3A32K7680 OSCILLATOR 32.7680 KHZ 1.5V SMD
3341-07 PROGRAMMING BOARD FOR PE3341
3342-07 PROGRAMMING BOARD FOR PE3342
TC70V3C32K7680 OSCILLATOR 32.7680 KHZ 1.5V SMD
相关代理商/技术参数
参数描述
SX1230 制造商:SEMTECH 制造商全称:Semtech Corporation 功能描述:Integrated Transmitter IC Narrow/wideband 315 MHz, 434 MHz 868 MHz and 915 MHz band Transmitter
SX1230-11SKA433 制造商:Semtech Corporation 功能描述:Evaluation Kit For SX1230-11SKA 433 mHz (SX1230SKA /SX1211SKA board) Transmitter
SX1230-11SKA868 制造商:Semtech Corporation 功能描述:NARROW/WIDEBAND RF TRANSMITTER 868MHZ
SX1230-11SKA915 制造商:Semtech Corporation 功能描述:NARROW/WIDEBAND RF TRANSMITTER 915MHZ 制造商:Semtech Corporation 功能描述:Evaluation Kit For SX1230-11SKA 915 mHz (SX1230SKA /SX1211SKA board)
SX1230-12SKA433 制造商:Semtech Corporation 功能描述:USB KIT - SX1230 433MHZ 制造商:Semtech Corporation 功能描述:Deluxe USB Starter Kit for SX1230, Includes Two USB Interface Boards at 433MHz