2.12 - DB37 [UE9 Datasheet] | LabJack
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2.12 - DB37 [UE9 Datasheet]

DB37 Overview

The DB37 connector brings out analog inputs, analog outputs, FIO, and other signals.  Some signals appear on both the DB37 connector and screw terminals, so care must be taken to avoid a short circuit.


Table 2.12-1. DB37 Connector Pinouts

DB37 Pinouts              
1 GND   14 AIN9   27 Vs
2 PIN2 (TX/200uA) 15 AIN7   28 Vm+
3 FIO6   16 AIN5   29 DAC1
4 FIO4   17 AIN3   30 GND
5 FIO2   18 AIN1   31 AIN12
6 FIO0   19 GND   32 AIN10
7 MIO1   20 PIN20 (RX/10uA) 33 AIN8
8 GND   21 FIO7   34 AIN6
9 Vm-   22 FIO5   35 AIN4
10 GND   23 FIO3   36 AIN2
11 DAC0   24 FIO1   37 AIN0
12 AIN13   25 MIO0      
13 AIN11   26 MIO2      


Figure 2.12-2. Standard DB37 pin numbers looking into the female connector on the UE9


 GND, Vs, AIN, DAC, FIO, and MIO are all described earlier. 

Vm+/Vm- are bipolar power supplies intended to power external multiplexer ICs such as the MAX4051A (maxim-ic.com).  The multiplexers can only pass signals within their power supply range, so Vm+/Vm- can be used to pass bipolar signals.  Nominal voltage is  ±5.8 volts at no load and ±5.6 volts at 1 mA.  Both lines have a 100 ohm source impedance, and are designed to provide 1 mA or less.  This is the same voltage supply used internally by the UE9 to bias the analog input amplifier and multiplexers.  If this supply is loaded more than 1 mA, the voltage can droop to the point that the maximum analog input range is reduced.  If this supply is severely overloaded (e.g. short circuited), then damage could eventually occur.

PIN2/PIN20 (TX0/RX0) bring out the UART transmit and receive lines on the UE9, but on other devices they bring out current sources.


We have suffered bad contact between our DB37/DB15 and the corresponding connectors on the UE9.

I think the DB37/DB15 we use may not be the mating connectors from the same manufacturer that Labjack use.

Could anyone provide the part number and the manufacturer for the DB37/DB15 connectors that UE9 use?



The DB15 & DB37 are standard 0.318" female d-sub connectors, and the exact part used at our factory can vary.  You should be able to use any male d-sub connectors.

The following pages from the U6 & T7 datasheets list some typical female connectors that someone might install on the OEM boards if needed:



In some circumstances it is possible to connect the DB connectors at a severe angle which pushes the internal contacts out of alignment.  If you sight down the outside of the female DB connector(s), you should be able to see gold shimmers from within each hole.  When the pins get pushed into the connector, or bent, then the gold connector inside won't reflect the light like the other pins do.  This visual test is the best way to see if the female connector has a problem. 

To re-align the pin, there are 2 options:

1) Open up the LabJack case with a PH1 screwdriver, removing the 6 screws, and look at the DB connector.  If the plastic backing seems to be sticking out at all (i.e. the backplate is not flush), then press the plastic backing plate on the DB connector so that it's flush again. This will move any depressed pins back out to the same plane as the rest of the pins.

2) If the pin isn't depressed, but it's instead just bent out of line, use a very small wire or tweezers tip to force the internal pin back into alignment.

The problem is that we are using the UE9.

Are you sure you provide the OEM version for the UE9 as well?

Please advise.

I am not sure what you are asking, but here is the UE9 OEM section, which pretty much says the UE9 is not produced in an OEM version.

As I mentioned earlier, we have suffered bad contact issue between our DB37/DB15 and the corresponding connectors on the UE9.

I believe the connectors on the UE9 are poor quality. If you provide OEM version of UE9, we could solder high quality DB connectors our own during our production.

Our company is NDI. we us quite a lot of UE9 for our products. For the time being, we have to manually solder lots of jumper wires to make the contacts reliable.

The UE9 is not produced in an OEM version, so the DB37 connector would have to be removed post-production.  I would not have a recommendation for any higher quality d-sub connectors, as the connectors we use have quality gold-plated contacts and we have not had issues with the contacts.  If the pins are in the proper place on the male and female connector (see comment from 13:44 below), we always see good connections.

If the DB37 was removed, you could then install a different DB37, solder wires directly to the PCB, or use the optional holes to install a pin header style connector.  See the attachment on the UE9 OEM section.  Contact [email protected] if you want a quote for UE9s with connectors removed and/or added.

Note that the newer T7 is available in an OEM version, so you could install any DB37 connector you wish, solder wires directly to the PCB, or use pin headers.