ald523d Advanced Linear Devices Inc (ALD), ald523d Datasheet - Page 10

• Manufacturer Part Number: ald523d
• Description: Multifunction 7-digit Serial Input Display Module Controller
• Manufacturer: Advanced Linear Devices Inc (ALD)

“L2DEC”, and “L3DEC” are 3 separate decimal point
placement instruction commands, each associated with
display set “DGS1”, “DGS2”, and “DGS3”, respectively.
Each command uses the same format, and has valid
parameters as “00”, “01”, “02”, “03”, “04”, and “05”.
“00” instructs the display module to display no decimal
point.
decimal point after the 1
module to display a decimal point after the 2
instructs the display module to display a decimal point
after the 3
display a decimal point after the 4
the display module to display a decimal point after the 5
digit.
In mode-B operation, the DEC1and DEC2 switches
change function and become M and Z switches in order to
perform a zero level adjustment. The M and Z switches
correspond to the control input pins 21 and 23 of the
ALD523D, respectively. They are functionally grouped
into J2. M and Z pins set logical states of operations as
described in Table 5.
The M switch is the master control switch, which controls
the Z switch. When the M=0, the Z switch function is
disabled, and the zero offset value is included in the
displayed reading.
turned on. At M=1 and Z=1, a zero level is indicated on
the CDM and the zero offset value is stored inside the
controller’s memory registers. When the M=1 and Z=0, a
reading with zero level shifting is displayed. In this mode,
the zero offset value previously stored is read back from
the controller’s memory registers and subtracted from the
current reading. The displayed reading now has automatic
zero correction. This function is analogous to the TARE
button in many weigh scales.
SELECTING AND CONFIGURING DIGITS
BLANKING
The ALD523D uses B1 and B2 as control-input pins for
setting the “blanking” of the trailing digits of the display’s
decimal digits. B1 and B2 switches can be applied in all
ALD523D
Table 5. Zero level switch configurations and operations for
GROUP
FUNCTION
PIN
SWITCHES
LOGIC LEVEL
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“01” instructs the display module to display a
mode-B
rd
digit. “04” instructs the display module to
.
21
M
0
1
1
When M=1, zero level shifting is
12/01
st
23
Z
X
0
1
digit. “02” instructs the display
ZERO LEVEL SHIFTING OFF
ZERO LEVEL SHIFTING ON
SET ZERO LEVEL
ZERO LEVEL
th
J2
digit. “05” instructs
OPERATION
nd
digit. “03”
http://www.aldinc.com
th
modes of operations with 4 combinations as shown in
Table 6.
numbers of digits to be displayed.
When the label/unit
parameter is set to 7-characters, at B1=0 and B2=0, the
ALD523D sets the display module to display a full 7-digit
number. When the label/unit “UNT1” or “UNT2” or
“UNT3” parameter is set to 8-characters, at B1=0 and
B2=0, the ALD523D sets the display module to display a
full 6-digit number.
When B1=1 and B2=0, the ALD523D instructs the display
module to blank the last display digit, and the display now
displays a 6-digit number.
ALD523D blanks the last two digits of the display, and the
display now show only a 5-digit number. Likewise at
B1=1 and B2=1, the ALD523D sets the display to show
only the first 4 digits of the number.
SELECTING AND CONFIGURING
MEASUREMENT SAMPLE AVERAGING
One of the effective techniques to minimize measurement
noise and increase stability is to apply sampling to average
a number of serial data samples. The ALD523D uses this
technique to stabilize its serial data sample reading by
filtering out noise associated with these samples.
general, the higher the number of serial data samples, the
better the noise rejection, but it also takes longer for the
display to respond to the input changes.
recommended sample averaging of 8 offers a good
tradeoff between conversion time and noise rejection.
The ALD523D utilizes DSA1 and DSA2 as control-input
pins for selecting one of three different sets of data
sampling, namely “AVG1”, “AVG2”, and “AVG3”. In all
Table 6. Blanking switch combination for mode-A, mode-B,
GROUP
FUNCTION
PIN
SWITCHES
LABEL/UNIT
LOGIC LEVEL
and mode-C
Each logical state combination selects the
B1
4
0
1
0
1
.
“UNT1” or “UNT2” or “UNT3”
B2
5
0
0
1
1
(XXXXXXX)
(XXXXXX)
(XXXXX)
(XXXX)
7-Digits
6-Digits
5-Digits
4-Digits
DIGIT BLANKING
CHARACTER
At B1=0 and B2=1, the
UNIT
NUMBER OF DIGITS
7
J3
DISPLAYED
(XXXXXX)
(XXXXXX)
(XXXXX)
(XXXX)
6-Digits
6-Digits
5-Digits
4-Digits
CHARACTER
A default
UNIT
10 of 20
8
In