Tvs Diode Array Spa Diodes Page 18 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 - SP720 Series Peak Transient Current Capability for Long Duration Surges The peak transient current capability rises sharply as the width of the current pulse narrows. Destructive testing was done to fully evaluate the SP720's ability to withstand a wide range of transient current pulses. The circuit used to generate current pulses is shown in Figure 4. 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 SP720 'IN' input pin and the (+) current pulse input goes to the SP720 V- pin. The V+ to V- supply of the SP720 must be allowed to float. (i.e., It is not tied to the ground reference of the current pulse generator.) Figure 5 shows the point of overstress as defined by increased leakage in excess of the data sheet published limits. The maximum peak input current capability is dependent on the V+ to V- voltage supply level, improving as the supply voltage is reduced. Values of 0, 5, 15 and 30 voltages are shown. 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 Figure 5. When adjacent input pins are paralleled, the sustained peak current capability is increased to nearly twice that of a single pin. For comparison, tests were run using dual pin combinations 1+2, 3+4, 5+6, 7+9, 10+11, 12+13 and 14+15. The overstress curve is shown in Figure 5 for a 15V supply condition. The dual pins are capable of 10A peak current for a 10s pulse and 4A peak current for a 1ms pulse. The complete for single pulse peak current vs. pulse width time ranging up to 1 second are shown in Figure 5. + - CURRENT SENSE VOLTAGE PROBE 14 15 16 9 13 12 11 10 1 2 3 4 5 7 6 8 IN V- IN V+ IN + - R 1 ~ 10 TYPICAL SP720 V G V G ADJ. 10V/ATYPICAL R 1 (-) (+) C1 ~ 100 F C1 VARIABLE TIME DURATION CURRENT PULSE GENERATOR 0.001 0.01 0.1 1 PEAK CURRENT (A) 10 7 6 5 4 3 2 1 0 0V 5V 15V 100 1000 10 9 30V 15V 8 CAUTION: SAFE OPERATING CONDITIONS LIMIT THE MAXIMUM PEAK CURRENT FOR A GIVEN PULSE WIDTH TO BE NO GREATER THAN 75% OF THE VALUES SHOWN ON EACH CURVE. SINGLE PIN STRESS CURVES DUAL PIN STRESS CURVE V+ TOV-SUPPLY PULSE WIDTH TIME (ms) Showing the Measured Point of Overstress in Amperes vs pulse width time in milliseconds (T A = 25 o C) Figure 5: SP720 Typical Nonrepetitive Peak Current Pulse Capability Figure 4: Typical SP720 Peak Current Test Circuit with a Variable Pulse Width Input

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