Microcyber HT1200M, Руководство пользователя

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HART Modem ASIC | HT1200M | Page
Email | fang.siqi@microcyber.cn
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General Description
The HT1200M is a single-chip, CMOS modem for use in Highway Addressable
Remote Transducer (HART) field instruments and masters. The modem and a few
external passive components provide all of the functions needed to satisfy HART
physical layer requirements including modulation, demodulation, receive filtering,
carrier detect and transmit-signal shaping. The HT1200M is pin-compatible with the
SYM20C15. See the Pin Description and Functional Description sections for details
on pin compatibility with the SYM20C15.
The HT1200M uses Phase Continuous Frequency Shift Keying (FSK) at 1200 bits
per second. To conserve power the receive circuits are disabled during transmit
operations and vice versa. This provides the half-duplex operation used in HART
communications.
Features

Can be used in designs presently using the SYM20C15 or equivalent type chip

Single-chip, half-duplex 1200 bits per second FSK modem

Bell 202 shift frequencies of 1200 Hz and 2200 Hz

3.3V-5.0V power supply

Transmit-signal wave shaping

Receive band-pass filter

Low power: optimal for intrinsically safe applications CMOS compatible

Internal oscillator requires 460.8kHz crystal or ceramic resonator

Meets HART physical layer requirements

Industrial temperature range of -40 °C to +85 °C

Available in a 28-pin PLCC and 32-pin LQFP packages