ADLINK USB-7230/7250 Isolation I/O Module Operation Manual

ADLINK USB-7230/7250 Isolated Digital I/O Module Complete Application and Operation Guide

In the field of industrial automation testing and control, high voltage isolation, reliable digital signal monitoring and driving capabilities are the foundation for stable system operation. ADLINK USB-7230 and USB-7250, two digital I/O modules based on USB 2.0, provide engineers with a plug and play cost-effective solution with up to 2500V RMS isolation voltage, flexible channel configuration, and multifunctional installation. This article is based on the original hardware manual, providing a comprehensive interpretation of hardware architecture, pin definitions, functional operations, and software configuration. It also offers design suggestions in conjunction with practical engineering scenarios to help developers quickly get started and avoid common misconceptions.

Product positioning and selection differences

USB-7230 and USB-7250 cater to different output driver requirements:

USB-7230: Provides 16 optoelectronic isolated digital inputs, 16 isolated digital outputs (open drain MOSFET, maximum 250mA current per channel, 5-35V power supply), and 2 frequency/event counters. Suitable for scenarios that require a large number of digital outputs to drive small relays, LED indicator lights, or solid-state switches.

USB-7250: Provides 8 differential isolated digital inputs and 8 electromagnetic relay outputs (channels 0-3 are C-type relays, including normally open/normally closed/common terminals); Channels 4-7 are A-type relays, only normally open, and are also equipped with two counters. Suitable for situations where direct switching between AC/DC loads (up to 220VDC/250VAC, 2A) is required.

Both use USB bus power supply (5V @ 400mA), without the need for external power supply, and come standard with detachable screw terminals, multifunctional brackets (supporting desktop, DIN rail, and wall mounting), and locking USB cables to ensure reliable connection on industrial sites.

Detailed explanation of hardware interfaces and pin definitions

1. USB-7230 pin allocation (40 pin terminal)

The module provides two sets of 20 pin detachable terminals, with the following pin functions:

Pin signal Pin signal

1 DI0 21 DI8

2 DI1 22 DI9

3 DI2 23 DI10

4 DI3 24 DI11

5 DI4 25 DI12

6 DI5 26 DI13

7 DI6 27 DI14

8 DI7 28 DI15

9 COM 29 COM

10 CNT0 30 CNT1

11 CGND 31 CGND

12 DO0 32 IGND

13 DO1 33 DO8

14 DO2 34 DO9

15 DO3 35 DO10

16 DO4 36 DO11

17 DO5 37 DO12

18 DO6 38 DO13

19 DO7 39 DO14

20 VDD 40 DO15

Signal Description:

DI0~DI15: Isolated digital input, common terminal is COM. The input voltage ranges from 5 to 24V at high levels and 0 to 1.5V at low levels, and can also be connected to dry contacts (passive contacts). All inputs share a common COM, so when wiring, the reference ground or power common terminal of all DIs must be uniformly connected to the COM.

CNT0/CNT1: Input for frequency/event counter, reference ground is CGND. Supports up to 1MHz input frequency, 32-bit counting width, and can be triggered by software selection of rising or falling edge.

DO0~DO15: Isolated digital output, using open drain MOSFET structure, with IGND as the reference ground. The external load power supply needs to be connected to VDD (5-35V), with a maximum current of 250mA per channel (100% duty cycle). When DO is ON, MOSFET conducts, and current flows from VDD through the load into the DO pin and then to IGND.

VDD: The positive input of the external output power supply must be connected to the positive terminal of the load power supply.

2. USB-7250 pin allocation (40 pin terminal)

Pin signal Pin signal

1 DI0H 21 DI0L

2 DI1H 22 DI1L

3 DI2H 23 DI2L

4 DI3H 24 DI3L

5 DI4H 25 DI4L

6 DI5H 26 DI5L

7 DI6H 27 DI6L

8 DI7H 28 DI7L

9 NC0 29 NC0

10 NO0 30 COM0

11 NO1 31 COM1

12 NC1 32 NC1

13 NO2 33 COM2

14 NO2 34 NC2

15 NO3 35 COM3

16 NC3 36 NC3

17 NO4 37 COM4

18 NO5 38 COM5

19 NO6 39 COM6

20 NO7 40 COM7

(Note: Some pins in the table are duplicated, and there are layout differences in tables 1-3 of the original manual. In reality, the signal name should prevail: channels 0-3 are of type C, with COM, NO, and NC terminals.); Channels 4-7 are of type A, with COM and NO terminals. Please refer to Table 1-4 in the manual for specific details

Signal Description:

DI0H/DI0L~DI7H/DI7L: Differential isolated input pair. Each channel is independent, without a common terminal, and can be connected in any polarity (bidirectional), with a high level of 5-24V and a low level of 0-1.5V.

CNT0/CNT1: Same as USB-7230, but the reference ground is GND0/GND1 (independent ground terminal).

Relay output: COM is the common terminal, NO is the normally open terminal, and NC is the normally closed terminal (only channels 0-3). When the control bit is 1, COM and NO are conductive; When it is 0, COM and NC are conductive (type A relay is disconnected). The rated power of the contact is 60W/125VA, the switching voltage is 220VDC/250VAC, the current is 2A, the action time is about 2ms, and the release time is 1ms.

Core Function Operation and Configuration

1. Isolate digital input and dry contact detection

USB-7230: All inputs share COM and can be connected using "common ground" or "common source". If an external NPN sensor (with a valid output low level) is connected, the sensor output can be connected to DI, the sensor common terminal can be connected to COM, and COM can be connected to the positive pole (common source) of the external power supply; If connected to PNP type, connect COM to the negative pole of the power supply (common ground). The input resistance is about 2.4k Ω (0.5W), ensuring normal operation within the range of 5-24V.