This document describes the features and characteristics of the STEL-1108 product, including functional block descriptions, input/output signal descriptions, mode control registers, register summaries, and electrical characteristics.
The STEL-1108 is a single ASIC digital modulator capable of operating at data rates up to 6.3 Mbps in BPSK mode and 12.6 Mbps in QPSK mode. It operates at a clock frequency of up to 126 MHz, allowing it to generate output signals at carrier frequencies up to 50 MHz. The device uses digital FIR filtering to optimally shape the spectrum of the modulating data prior to modulation, thereby optimizing the spectrum of the modulated signal while minimizing the analog filtering required after the modulator.
The STEL-1108 incorporates a Numerically Controlled Oscillator (NCO) to synthesize the carrier in the modulator. It features selectable 10- or 12-bit outputs and operates in continuous and burst modes. The device is designed to operate from a 3.3 volt power supply and includes provision to interface with other logic operating at 5 volts.
| Modulation Modes | BPSK / DBPSK / QPSK / DQPSK |
|---|---|
| Maximum Data Rate (BPSK) | 6.3 Mbps |
| Maximum Data Rate (QPSK) | 12.6 Mbps |
| Maximum Clock Frequency | 126 MHz |
| Power Supply Voltage | 3.3 V |
| Package Type | 80-pin MQFP |
The device supports BPSK, DBPSK, QPSK, and DQPSK modulation formats.
The maximum data rate for QPSK mode is 12.6 Mbps.
Yes, the device operates in both continuous and burst modes.