ad2033 Analog Devices, Inc., ad2033 Datasheet - Page 4

• Manufacturer Part Number: ad2033
• Description: Truerms /db M.ultirange,~meter.
• Manufacturer: Analog Devices, Inc.

ence Adjust or by control of an external reference (which can
be varied by controlling
can be divided down from a higher voltage).
il
Examples:
/"\~ ~IlUWIl III r Igun;
Adjustment
selecting the proper VSIG inpu t range and V REF' The 60dB
readout range can be offset anywhere within the total meter
range of +60dB to -60dB.
(Pins 1-6) on all ranges except the 1.999V rms FS Range.
Set up in similar fashion on other ranges.
voltage, put the following dc blocking capacitors at DPM'M
input:
To set up for a full scale of SOOmV input range, link Feed-
AD2033 to measure and display a bipolar dc value on the
Ground (Pins 1-6). A shunt capacitor (0.047/-LF) at the AID
Ac Coupling Input of AD20H
For measurements of ac voltages superimposed upon de >C
Measurement of Very Low Frequencies.
about 30Hz, the AD2033 will "track" the input signal and
VOL. II, 16-46 DIGITAL PANEL
back Range Select (Pin A) to Feedback (Pin F). Connect
source between 200mV Input (Pin E) and Ground (Pins 1-6).
Connect dB Reference In (Pin U) to dB Reference Out
(Pin 17) for use of internal reference and then link dB Out-
put (Pin V) to AID Input (Pin 18). To use external reference,
connect source between dB Reference In (Pin U) and Analog
Ground (Pins 1-6). Since the input pin for this range is Pin E,
the Input Pin (Pin K) for all other ranges must be grounded
and the Bias Current Compensate must be linked to Ground
Bipolar dc Measurements
By bypassing the nos/dB front end, it is possible to use the
the AID Input Pin (Pin 18 of P2). Connect low side to
Input is needed to limit input impedance.
If the input signal to be measured has a frequency of dc to
1.999V FS. The input pin for this measurement
z
"
Figure
625V
soovi
sovl
20V!
5V
All Others
200mV
-
CAUTION
3.
Range
NOTE'
SOOV
0.5v 0.05V O.OO5V
50vI
dB
5vl
2VI
VREF
dB readout range is O.OOdBto -60dB.
2. VSIc:;
1. VSIG
with VREF
full dB readout range is +20dB to -40dB.
l l l
of the dB range can also be accomplished
ON OTHER
FIGURE 3 IS SET UP FOR ABSOLUTE VOLTAGES ON THE 5V SCALE. 2OdB
CORRECTION
Readout
0.5V!
02VI 0.02V
50V
THERE
5V
=
0.05\1 O.OO5V
=
=
SV. dB readout
IS NO INPUT
:>, UD reaaou
Capacitor (Rated Accuracy at 45Hz)
5V
RANGES
SOV rms on the SOV ems range with
SOV ems on the SOOVrms range
PER DECADE
as a
=
VREF' either via the Internal Refer-
0.5V
O.SV. dB readout
Function of VSIG and VREF
OVERLOAD
WOULD
r ror
INSTRUMENTS
0.1/-LF
=
I/-LF
INDICATION
BE NEEDED
VAEF
O.OOdB and the full
a par(ICUlar
=
IF VAEF
IN d8 MODE
O.OOdB and the
would be
REMAINS
V SIG can
by
ACCURACY
'1SdB
ACCURACY
'O.SdB
ABSOLUTE
KEY
KEY
The AD20B
The output data is latched and is valid except for a 2ms
period at the end of conversion, when the "Data Ready"
output is high (See Figure 1). As described above, the
"Data Hold" input can be used to inhibit updating of the
parallel dara outputs without affecting DPM conversions or
the DPM display.
counts, and the display flashes to indicate overrange beyond
this point, measurements
mately 3000 counts. Since it is impossible to display "2"
in the most significant digit of the AD2033, overrange from
2000 to 2999 counts produces a flashing display of the 3
least significant digits only (a reading of 2.300mV displays
as "300" flashing). Overrange beyond 2999 counts is indi-
cated by a constant number flashing. Thus, one can use the
extra range measurements
to the normal range. The parallel BCD outputs of the
AD20B
lines, as does the Overload Output.
capacitor to be attached. Table 2 will aid in choosing the
proper value of averaging capacitance.
Interfacin~ Data Outputs
Although the full scale display range of the AD2033 is 1999
extend the low trequency
are provided at the connector
Extended True ems ac Range Measurements
r-i
PIN
PIN
10
11
12
13
14
16
16
17
10
11
12
13
14
15
18
2
3
4
7
8
9
2
3
4
7
8
9
1
1
BCD 200
DISPLAY BLANK
OVERRANGE
ac LINE HIGH
FUNCTION
ANALOG LOW
ANALOG LOW
ANALOG LOW
ANALOG LOW
ANALOG LOW
ANALOG LOW
dB REF OUT (0 TO .sv)
AID INPUT
FUNCTION
DATA HOLD
DATA READY
POLARITY
BCD 8
BCD 2
BCD80
BCD 20
BCD 800
BCD 400
Frequency
beyond 1999 counts go to Logic "0" on all BCD
25Hz
10Hz
Figure 5. AD2033 Connector P2
Table 2. External Capacitor Selection
Figure 4. AD2033 Connector P1
has data outputs in a full parallel BCD format.
tl.999V
FS ,
Averaging
Capacitor
Value
IS/-LF
100/-LF
-
are actually made up to approxi-
as a guide to reducing the input
IKEY
KEY
response ot the AD2033, cwo pinS
Parallel BCD
...
-f
-t
of P2 to allow an external
.U
.H
C
H
J
M
N
S
To
V
PIN
A
B
0
K
L
R
PIN
A
B
C
0
J
K
L
M
N
P
R
S
dB REP IN (OPTIONAl)
dB REF IN (+&mV .. VRIV .. .sVI
BIAS CURRENT COMPENSATE
RANGE E FEEDBACK
RANGE 0 FEEDBACK
RANGEC
RANGEA ANDB
rml OUT t1.999V'FSlEX":'cAP (+\
EXT CAP H
dB OUT (2OOmVIDECADE)
SHIELD (EARTH GROUND)
FUNCTION
RANGE SELECT (CONNECT TO C,D,E.F)
INPUT(EXCEPT
FUNCTION
N/C
N/C
OVERLOAD
CONVERTERHOLD
BCD 1
BCD 4
BCD 10
BCD 40
BCD 100
DP3 XX.X
DP2 X.XX
DIGITAL GROUND
DP1 .XXX
Ie LINE LOW
Rated Accuracy
Settling Time tl?
6 Seconds
30 Seconds
200mV)