The MAX199 multi-range, 12-bit data-acquisition system
(DAS) requires only a single +5V supply for operation,
and converts analog signals up to ±4V at its inputs. This
system provides eight analog input channels that are
independently software programmable for a variety of
ranges: ±VREF, ±VREF/2, 0V to VREF, or 0V to VREF/2.
This increases effective dynamic range to 14 bits, and
provides the user flexibility to interface 4mA-to-20mA,
±12V, and ±15V powered sensors to a single +5V system.
In addition, the converter is fault-protected to
±16.5V; a fault condition on any channel will not affect
the conversion result of the selected channel. Other features
include a 5MHz bandwidth track/hold, 100ksps
throughput rate, internal/external clock, internal/external
acquisition control, 8+4 parallel interface, and operation
with an internal 4.096V or external reference.
A hardware active-low SHDN pin and two programmable power-down
modes (STBYPD, FULLPD) provide low-current
shutdown between conversions. In STBYPD mode, the
reference buffer remains active, eliminating start-up
delays.
The MAX199 employs a standard microprocessor (µP)
interface. Its three-state data I/O interface is configured
to operate with 8-bit data buses, and data-access and
bus-release timing specifications are compatible with
most popular µPs. All logic inputs and outputs are
TTL/CMOS compatible.
The MAX199 is available in 28-pin DIP, wide SO, SSOP,
and ceramic SB packages.
For a different combination of input ranges (±10V, ±5V,
0V to 10V, 0V to 5V), see the MAX197 data sheet. For 12-bit
bus interfaces, see the MAX196/MAX198 data sheet.