Tvs Diode Array Spa Diodes Page 36 TVS Diode Array SPA Diodes Catalog

2017 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 02/23/17 TVS Diode Arrays (SPA Diodes) General Purpose ESD Protection - SP724 Series Peak Transient Current Capability for Long Duration Surges The peak transient current capability is inversely proportional to the width of the current pulse. Testing was done to fully evaluate the SP724's ability to withstand long duration current pulses using the circuit of Figure 4. Figure 5 shows the point of overstress as defined by increased leakage in excess of the data sheet published limits. The safe operating range of the transient peak current should be limited to no more than 75% of the measured overstress level for any given pulse width as shown in the curve of Figure 5. The test circuit of Figure 4 is shown with a positive pulse input. For a negative pulse input, the (-) current pulse input goes to an SP724 'IN' input pin and the (+) current pulse input goes to the SP724 V- pin. The V+ to V- supply of the SP724 must be allowed to float. (i.e., It is not tied to the ground reference of the current pulse generator.) Note that two input pins of the SP724 may be paralleled to improve current (and ESD) capability. The sustained peak current capability is increased to nearly twice that of a single pin. + - CURRENT SENSE VOLTAGE PROBE + - R 1 ~ 10 TYPICAL SP724 V X V X ADJ. 10V/ATYPICAL R 1 (-) (+) C1 ~ 100 F C 1 VARIABLE TIME DURATION CURRENT PULSE GENERATOR 1 2 3 6 5 4 0.001 0.01 0.1 1 10 7 6 5 4 3 2 1 0 100 1000 8 SQUARE WAVE PULSE WIDTH (ms) PEAK CURRENT (A) NOTE: TO ENSURE SAFE OPERATION LIMIT THE MAXIMUM PEAK CURRENT FOR A GIVEN PULSE WIDTH TO BE NO GREATER THAN 75% OF THE VALUES SHOWN. T A = 25C V+ TO V-SUPPLY = 15V Showing the Measured Point of Overstress in Amperes vs pulse width time in milliseconds Figure 5: SP724 Typical Nonrepetitive Peak Current Pulse Capability Figure 4: Typical SP724 Peak Current Test Circuit with a Variable Pulse Width Input

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