DMS-20PC-4/20P Murata Power Solutions Inc, DMS-20PC-4/20P Datasheet - Page 3

• Manufacturer Part Number: DMS-20PC-4/20P
• Description: DATEL PANEL METERS
• Manufacturer: Murata Power Solutions Inc
• Type: Digital Process Monitorr

Specifications of DMS-20PC-4/20P

• Rohs Compliant: NO
• Equipment Type: Digital Process Monitor
• Input: + 20 V
• Display Type: 3 - 1/2 Digit LED
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

4. DISPLAY TEST/HOLD (Pin 9) Function: Pin 9 is a dual-function
5. DISPLAY ENABLE (Pin 2) Function: On all models, tying pin 2 to
6. Gain Adjust: There is a gain-adjust potentiometer on the back of
7. Soldering Methods: All models in the DMS-20PC Series easily with-
pin. On all standard models (without "-H" suffi x), tying pin 9 to pin 1
(+5V SUPPLY) activates the meter's DISPLAY TEST feature. All display
segments, except the decimal points, will be illuminated. The display
will show "1888" ("–1888" if a negative input signal is present). Do
not leave the meter in the test mode for more than 10 seconds as
this will cause the meter's operating temperature to rise and possibly
affect its performance. Pin 9 must be left open when the test function
is not being used.
On models with the "-H" suffi x (DMS-20PC-1-RS-H for example), pin
9 serves as a DISPLAY HOLD control pin. Tying pin 9 to +5V SUPPLY
(pin 1) on these models will hold or "freeze" the current display read-
ing indefi nitely. Pin 9 must also be left open when the hold function is
not being used. After disabling DISPLAY HOLD, allow the meter a full
10 seconds to resume normal calibrated operation before holding a
new reading.
The DISPLAY TEST or DISPLAY HOLD pin should normally be con-
nected, via a selector switch, to pin 1 (+5V SUPPLY). If automatic,
logic-controlled operation is desired, only PNP or MOSFET transis-
tors should be used. The base or gate of these transistors should be
driven suffi ciently hard to bring pin 9 within 0.05V of +5V SUPPLY.
pin 1 (+5V SUPPLY) applies full power to the LED display. This is the
normal mode of operating the meter. Leaving DISPLAY ENABLE open
(no connection), only turns off the LED display. The meter's analog-
to-digital converter continues to sample the input signal. Total current
consumption with the display off is approximately 400μA (0.4mA).
This is a very useful feature if the meter is used in battery-powered
equipment.
With the exception of the low-power red LED models (DMS-20PC-X-
RL), a regulated voltage lower than +5V SUPPLY can be used to dim
the display intensity. Display intensity control is best performed with
the high brightness, red LED, DMS-20PC-X-RH model. All low-power
red LED models must have DISPLAY ENABLE tied directly to pin 1
(+5V SUPPLY). Voltages applied to DISPLAY ENABLE must never be
greater than +5V SUPPLY.
each meter. It has approximately ±50 counts (±2.5%) range of
adjustment. Since these devices essentially have no zero/offset
errors, a gain adjustment is effectively an overall accuracy adjust-
ment. Though they may be performed at any point (except zero),
accuracy adjustments are most effective when performed with
higher level input signals. The circuit shown in Figure 10 provides
±10% range of adjustment.
stand most common wave soldering operations. We recommend,
however, that you evaluate the effects your particular soldering
techniques may have on the meter’s plastic case and high-precision
electrical performance. We recommend the use of no-clean solders.
www.murata-ps.com/dpm
8. Suggested Mating Connectors:
1. Single-Ended Input Confi gurations: True single-ended measure-
APPLICATIONS
DMS-20PC meters are highly versatile devices that can be used in
hundreds of applications. The application circuits chosen for this section
are ones that have historically received many inquiries.
The schematic in Figure 1 shows that the meter's high-impedance input
consists of an op amp powered from a ±5Vdc power supply (the –5V is
internally generated). One can easily see why input signals applied to (–)
INPUT LO and (+) INPUT HI have to be kept within the power supply rails
of ±5V. Also note that only pin 11 has a current-limiting 909kΩ series
resistor. High input voltages that have a common ground with pin 3 (5V
RETURN) should only be applied to pin 11 ((+) INPUT HI) and never to pin
12. In these high-voltage cases, pin 12 should always be tied to pin 3
(5V RETURN).
The schematic also shows that pin 3 is the meter's zero-volt reference
point — regardless of the type of power or signal source used. This is
an important point to keep in mind when a digital or analog multimeter
is used to make system measurements. The multimeter's negative lead
(usually the black one) must be connected to pin 3 (5V RETURN).
3½ Digit, LED Display, Low-Cost, Subminiature
85-264Vac
Panel mounted:
Connector housing
Terminal type
Crimping tool
Wire size
Insulation diameter
Stripping length
Board mounted:
Socket DATEL P/N 4320-01074-0
ments can be made with any DMS-20PC meter. The circuit of Figure
2 avoids problems normally associated with ground-loop currents.
Separate ground runs should be used for 5V RETURN (pin 3) and (–)
INPUT LO (pin 12).
+
–
V
IN
AC to DC Converter
Figure 2. Single-Ended Input Confi guration
(–) IN LO
(+) IN HI
+5V SUP
DMS-20PC Series
15 Feb 2010 MPM_DMS_20PC.D06 Page 3 of 6
11
12
1
DATEL P/N 4320-01069-0
DATEL P/N 4400-01032-0
DATEL P/N 39-2099000
22 to 26 AWG
0.062" (1.57mm) maximum
0.100 to 0.125" (2.54 to 3.17mm)
Digital Panel Voltmeters
DMS-20PC-1
2
DISPLAY
ENABLE
email: [e-mail]
6
DP1
3
5V RET
8
REF OUT
7
REF IN