THE SPECS
The MS1001 offers multiple front-end inputs for LW/MW/SW (150 kHz to 30 MHz),
VHF Band II (76 to 108 MHz), Band III (174 to 240 MHz), Band IV/V (470 to 960
MHz), and L-band (1450 to 1675 MHz) (Fig.
1). Separate low-noise amplifiers (LNAs) are provided, in addition to all
input switching. A few capacitors are needed on the front end for impedance
matching.
The LW/MW input is designed to take an external ferrite antenna. Most of these
inputs may be connected in a balanced or unbalanced configuration. The typical
input impedance is 75 or 100 Ω. An external balun is needed on the L-band
input.
A fast-settling fully integrated synthesizer drives the I/Q mixers. An external
crystal reference is required, but the master oscillator in a cell phone or
other host device usually will supply it. The IF may be set to a low IF value
(typically 450 kHz or less) or zero for direct conversion. The IF/baseband does
the filtering once the mixers are fully programmable from 300 kHz to 4 MHz.
The automatic-gain-control (AGC) amps are available at the outputs to be sent
to the analog-to-digital converters (ADCs) and baseband processor for signal
recovery. The output voltage ranges up to a 4-V p-p differential. A three-wire
serial port is used for all programming and control. The external parts count
is very low, but it depends significantly on the bands and modes being used.
Power consumption is another crucial specification when making a chip for battery-powered
devices. The MS1001 was designed with low-power operation in mind. In fact,
the company claims that the chip has the lowest power consumption of any tuner
announced to date.
As an example, it draws only 46 mA when operating in the L-band with DVB-H
mobile TV. Power consumption drops to 13 mW with the 10% time-slicing that's
a part of the DVB-H standard. In powered-down mode, the chip draws less than
10 A.
The MS1001, which comes in a 6- by 6-mm, 40-pin quad flat no-lead package,
costs $3.50 in 10,000-unit quantities. Samples are available now. A customer
sample board goes for $1000 (Fig. 2).
Mirics Semiconductor Inc.
www.mirics.com