FEATURES *Programmable gain
*PLL controlled carrier frequency
*3-wire transmission bus
*5V supply voltage. APPLICATIONS *QPSK modulation GENERAL DESCRIPTION The Quadrature Phase Shift Keying (QPSK) transmitter IC is a monollthic bipolar IC dedicated to quadrature modulation of the I and Q signals. It includes: *Two double balanced mixers
*A balanced voltage controlled oscillator (VCO) with 0 to 90 degrees signal generation for modulation
*A phase locked loop (PLL) for IF frequency control
*A conversion mixer
*A PLL for RF frequency control
*A gain controlled output amplifier
*A 3-wire bus and an output buffer. Two PLLs are incorporated the first PLL includes: - A fixed main divider
- A crystal oscillator and its programmable reference divider
- A phase/frequency detector, combined with a fixed charge pump. The second PLL includes
- A divide-by-four preamplifier
- A 12-bit programmable divider
- A crystal oscillator and its programmable reference divider
- A phase/frequency detector, combined with a programmable charge pump which drives the tuning amplifier, including 30 V output.
| Power: | 230V/Ac Mains operated. | | Housing: | Mounted in sloping Fiber cabinet. | | Dimension: | 41.5cms X 31.5cms X 13.5cms | | Weight: | 750 gms |
|
