Rainbow Electronics MAX1301 - Manual (Page 13)

Detailed Description
The MAX1300/MAX1301 multirange, low-power, 16-bit
successive-approximation ADCs operate from a single
+5V supply and have a separate digital supply allowing
digital interface with 2.7V to 5.25V systems. These 16-bit
ADCs have internal track-and-hold (T/H) circuitry that
supports single-ended and fully differential inputs. For
single-ended conversions, the valid analog input voltage
range spans from -12V below ground to +12V above
ground. The maximum allowable differential input volt-
age spans from -24V to +24V. Data can be converted in
a variety of software-programmable channel and data-
acquisition configurations. Microprocessor (µP) control is
made easy through an SPI-/QSPI-/MICROWIRE-compati-
ble serial interface.
The MAX1300 has eight single-ended analog input
channels or four differential channels (see the Block
Diagram at the end of the data sheet). The MAX1301
has four single-ended analog input channels or two dif-
ferential channels. Each analog input channel is inde-
pendently software programmable for seven
single-ended input ranges (0 to +6V, -6V to 0, 0 to
+12V, -12V to 0, ±3V, ±6V, and ±12V) and three differ-
ential input ranges (±6V, ±12V, and ±24V).
Additionally, all analog input channels are fault tolerant
to ±16.5V. A fault condition on an idle channel does not
affect the conversion result of other channels.
MAX1300/MAX1301
8-/4-Channel, ±12V Multirange Inputs,
Serial 16-Bit ADCs
______________________________________________________________________________________ 13
Pin Description (continued)
PIN
MAX1300 MAX1301
NAME FUNCTION
21 18 AGND3
Analog Signal Ground 3. AGND3 is the ADC negative reference potential. Connect AGND3 to
AGND1. DGND, DGNDO, AGND3, AGND2, and AGND1 must be connected together.
22 19 AV DD2
Analog Supply Voltage 2. Connect AV
DD2
to a +4.75V to +5.25V power-supply voltage. Bypass
AV DD2 to AGND2 with a 0.1µF capacitor.
23 20 AGND2
Analog Ground 2. This ground carries approximately five times more current than AGND1.
DGND, DGNDO, AGND3, AGND2, and AGND1 must be connected together.
24 1 AGND1 Analog Ground 1. DGND, DGNDO, AGND3, AGND2, and AGND1 must be connected together.
4–20mA
PLC
ACCELERATION
PRESSURE
TEMPERATURE
WHEATESTONE
WHEATESTONE
1 µF
0.1 µF AGND2 DGNDO AGND3 DGND
AV DD2 DV DD AV DD1
0.1 µF 0.1 µF 0.1 µF
5.0V 5.0V 5.0V
MAX1300
CHO
CH1
CH2
CH3
CH4
CH5
CH6
CH7
REF
AGND1
REFCAP
0.1 µF
3.3V
MC68HCXX
µC
DV DDO
SCLK
CS
DIN
SSTRB
DOUT
V DD
SCK
I/O
MOSI
I/O
MISO
V SS
Figure 1. Typical Application Circuit