ISLA112P50 Intersil, ISLA112P50 Datasheet - Page 28

• Manufacturer Part Number: ISLA112P50
• Description: 500MSPS A/D Converter
• Manufacturer: Intersil

ADDRESS 0XC2: USER_PATT1_LSB
ADDRESS 0XC3: USER_PATT1_MSB
These registers define the lower and upper eight bits,
respectively, of the first user-defined test word.
ADDRESS 0XC4: USER_PATT2_LSB
ADDRESS 0XC5: USER_PATT2_MSB
These registers define the lower and upper eight bits,
respectively, of the second user-defined test word.
VALUE
0000
0001
0010
0011
0100
0101
0110
0111
1000
TABLE 16. OUTPUT TEST MODES
Negative Full-Scale
Positive Full-Scale
OUTPUT TEST
Checkerboard
User Pattern
0xC0[3:0]
One/Zero
Reserved
Reserved
Midscale
MODE
Off
28
user_patt1 user_patt2
WORD 1
0xAAAA
0x8000
0x0000
0xFFFF
0xFFFF
N/A
N/A
WORD 2
0x5555
0x0000
ISLA112P50
N/A
N/A
N/A
N/A
N/A
Digital Temperature Sensor
This set of registers provides digital access to an
IPTAT-based temperature sensor, allowing the system to
estimate the temperature of the die. This information is
of particular interest for applications that do not keep I2E
in Active Run state when in normal use, allowing easy
access to information that can be used to decide when to
recalibrate the A/D as needed. This set of registers is not
included in the SPI memory map table.
The most accurate usage of this information requires
knowledge of the temperature at which the digital value
is first read (time = 0, T(0) = degrees C at time = 0, and
register_value(0) = the digital value of the temperature
registers at time = 0). Any future reading of the registers
indicates temperature change according to Equation 4:
ΔT
A less accurate method for evaluating the temperature
change does not require knowledge of the temperature
at time = 0, and is given by Equation 5:
ΔT
The digital temperature sensor is a weak function of the
AVDD supply voltage, so to achieve best accuracy the
AVDD supply voltage should be held fairly constant
across the operarating temperature range.
The algorithm to access this set of registers is as follows:
1. Write the value 0x80 to the Index Register (SPI
2. Write the value 0x88 to SPI address 0x120 to turn
3. Read the register_value LSBs at SPI register 0x11E
4. Read the register_value MSBs at SPI register 0x11F
5. Write the value 0x60 to SPI address 0x120 to turn
=
=
address 0x10)
the temperature sensor on.
the temperature sensor off.
T 1 ( ) T 0 ( )
T 1 ( ) T 0 ( )
–
–
=
=
[
---------------------------------------------------------------------------------------------------------------- -
[
---------------------------------------------------------------------------------------------------------------- -
register_value(1)
register_value(1)
[
(
T 0 ( ) 216
(
–
-0.72
]
]
–
–
[
[
register_value(0)
register_value(0)
)
) 256
⁄
www.DataSheet4U.com
]
March 30, 2010
FN7604.0
(EQ. 4)
(EQ. 5)
]
]