LabJack U3 User Manual

2.13 Hardware Revision Notes
Starting September of 2006, all U3 shipments changed from hardware revision 1.20 to 1.21.
Following are the some of the main changes in revision 1.21:
• The default timer clock frequency is 48 MHz.
• All TimerBaseClock frequencies are twice the previous frequencies.
• The input timer edge limit is now 30,000 edges/second, compared to the old limit of
10,000 edges/second.
• Stream mode is now supported. See Section 3.2.
• Other new functions are supported, including Watchdog, SPI, Asynch, I2C, and SHT1X.
• Typical supply current is 50 mA.
Older U3s can be upgraded by LabJack for a small fee. For information about upgrading a rev
1.20 unit, go to labjack.com.
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LabJack U3 Specifications

General

Analog Outputs	2
Analog Output Resolution	10 bits
Digital I/O	20
Counter/Timers	2
Interface	USB
Operating Voltage	5 V
Manufacturer	LabJack Corporation
Analog Inputs	16
Analog Input Resolution	12-bit
Max Sample Rate	50 kHz