PIN FUNCTIONS

SPECIAL NOTE - ANNUNCIATORS.

1. V-

Negative power supply connection.

2. IH

Positive measuring input.

Analogue inputs must be no closer than 1V to either the positive or negative supply. The negative

3. IL

Negative measuring input. supply of an S-type meter is generated internally and mirrors the positive supply voltage.

4. COM

The ground for the analogue section of the A/D converter, held actively at 2.8V (nom.) below V+. COM must not be allowed to sink

excessive current (>100 A) by connecting it directly to a higher voltage.

5. REF LO

Negative input for reference voltage.

6. REF HI

Positive input for reference voltage (connected via Link 1 to REF+).

7. POL

Drive for negative (-) annunciator. Internally connected via Link 11 to the annunciator.

8, 10, 15, 19

Outputs for autoranging applications.

9. BP

LCD back plane drive waveform.

11. REF+

Positive output from internal reference (connected via Link 1 to REF HI).

12. REF-

Negative output from internal reference. MUST be tied to a suitable ground return to bias bandgap (normally COM).

13. R BG

Ouput of bandgap reference (1.22V nom).

14. V+

Positive power supply connection.

16. CLOCK Clock output. May be used for systems timing or as an input to override the internal oscillator and control the sample rate.

17. -5V

Output from negative rail generator circuit (DPM 2000S only). This is an inversion of V+.

18. XDP

Connect to required annunciators/DPs (see Special Note - Annunciators).

20. TEST

Connect to V+ to momentarily turn on segments as illustrated. It should not be operated for more than a few seconds as the D.C.

voltage applied to the LCD may 'burn' the display. This pin is 5V (nom) below V+ and is the ground for the digital section of the meter.

It can be used to power external logic up to a maximum of 1mA.

µ

The DPM annunciators (DPs, °C, etc.) can be displayed either by connecting to XDP

or by applying a solder blob link to the XDP pads located under the annunciator input

pads. However, as these annunciators are normally 'floating', under certain conditions

they may appear when not wanted. To suppress unwanted annunciators, apply a

solder blob to the backplane pads located in-between the annunciator input pads.

If the annunciators are being switched, connect them via M resistor to the BP

(Pin 9), the annunciators will then operate normally when connected to XDP. Ensure

that an annunciator is not connected directly to the XDP and BP at the same time.

Note - if suppressing POL (-) annunciator by direct connection to BP then Link 11

MUST be cut first.

Ω

VARIOUS OPERATING MODES

ON-BOARD LINKS: In order to quickly and easily change operating modes for

different applications, the meter has several on-board links. They are designed

to be easily opened (cut) or shorted (soldered).

Do not connect more than one meter to the same power supply if the meters cannot

use the same signal ground. Taking any input beyond the power supply rails will

damage the meter.

Measuring current (supply MUST be isolated).

Measuring 4-20mA to read 0-999

(supply MUST be isolated).

Split supply operation (DPM 2000).

Measuring a floating voltage source of 200mV

full scale.

Measuring a single ended input

referenced to supply (DPM 2000S).

Measuring the ratio of two voltages.

Reading = 1000 V /V

50mV <

<200mV

12

V

V< 2V

2

12.

Check Links 3 & 4 are SHORTED.

Check Links 3 & 4 are SHORTED.

Check Links 3 & 4 are SHORTED.

Check Links 2, 3 & 4 are SHORTED.

Check Links 2, 3 & 4 are SHORTED.

Check Link 1 is OPEN.

ANNUNCIATOR

ANNUNCIATOR

BP

XDP

XDP

Link either BP or XDP

to annunciator.

RIGHT

Normally

SHORTED

Cut to

OPEN

Normally

OPEN

Solder to

SHORT

5

+

+

-

-

6 REF HI

IN HI

REF LO

IN LO

14

3

1

V-

V-

2

V+

V+

V-

V+

3

2

1

14

6R2

SET

ZERO

100K

5K

4

13

IN HI

IN LO

COM

REF BG

V-

V+

2

V-

V-

V+

V+

14

1

3

R

R= 0.2

IN

HI

IN

LO

3

+

-

±200mV

2 IN HI

IN LO

14

1

V-

V-

V+

V+

3

2

V-

V-

V+

V+

±200mV

14

1

+

-

IN

HI

IN

LO

V+

V+

14

3

2

IN HI

IN LO

1

0V

1vmin.

14V max.

7V min.

V-

V-

+

-

±200mV

Specifications liable to change without prior warning

DPM 2000

Issue 3

August/1997

M.C.

Applies to DPM 2000/5

ANNUNCIATOR

ANNUNCIATOR

BP

XDP

XDP

Do not link BP & XDP

to the annunciator

at the same time

WRONG

Martel Electronics, Corp. P.O. Box 770 Londonderry, NH 03053

Toll Free: (800) 821-0023 Phone: (603) 434-1433 Fax: (603) 434-1653