SP721 Series - SCR/Diode Array for ESD and Overvoltage Protection

Series: SP721
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The SP721 is an array of SCR/Diode bipolar structures for ESD and over-voltage protection to sensitive input circuits. The SP721 has 2 protection SCR/Diode device structures per input. There are a total of 6 available inputs that can be used to protect up to 6 external signal orbus lines. Over-voltage protection is from the IN (Pins 1 - 3 and Pins 5 - 7) to V+ or V-.

The SCR structures are designed for fast triggering at a threshold of one +VBE diode threshold above V+ (Pin 8) or a -VBE diode threshold below V- (Pin 4). From an IN input, a clamp to V+ is activated if a transient pulse causes the input to be increased to a voltage level greater than one VBE above V+. A similar clamp to V- is activated if a negative pulse, one VBE less than V-, is applied to an IN input.

Features:

  • ESD Interface Capability for HBM Standards
    • MIL STD 3015.7 ....................................15kV
    • IEC 61000-4-2, Direct Discharge,
    • Single Input............................................4kV (Level 2)
    • Two Inputs in Parallel..............................8kV (Level 4)
    • IEC 61000-4-2, Air Discharge..................15kV (Level 4)
  • High Peak Current Capability
    • IEC 61000-4-5 (8/20µs)..........................±3A
    • Single Pulse, 100µs Pulse Width...............±2A
    • Single Pulse, 4µs Pulse Width..................±5A
  • Designed to Provide Over-Voltage Protection
    • Single-Ended Voltage Range to................+30V
    • Differential Voltage Range to...................±15V
  • Fast Switching................................................2ns Rise Time
  • Low Input Leakages........................................1nA at 25°C Typical
  • Low Input Capacitance....................................3pF Typical
  • An Array of 6 SCR/Diode Pairs
  • Operating Temperature Range........................-40°C to 105°C

Applications:

  • Microprocessor/Logic Input Protection
  • Data Bus Protection
  • Analog Device Input Protection
  • Voltage Clamp

Access specifications, certifications, check availability and order parts below

Catalog #Standoff
Voltage
(V)		ESD Contact
(kV)		ESD Air
(kV)		Lightning
Immunity
(8x20μs)
(A)		CI/OTYP
(pF)		PolarityChannelsPackageCompare
SP721AB
Obsolete: 2008 -05-08
Replaced By: SP721ABG 		3041533Bidirectional6SOIC-8L
SP721ABT
Obsolete: 2008 -05-08
Replaced By: SP721ABTG 		3041533Bidirectional6SOIC-8L
SP721AP
Obsolete: 2008 -05-08
Replaced By: SP721APP 		3041533Bidirectional6PDIP-8L
To request product environmental information, please complete the Product Environmental Information Request Form.

pdficon ESD and Transient Protection Using the SP720 Application Note

This application note discusses ESD and transient protection using the SP720. For a given level of voltage or power there is a defined degree of protection compatible to that need. For the SP720 the protection circuits are designed to clamp over-voltage within a range of peak current that will substantially improve the survival input expectancy of average monolithic silicon circuits used for small signal and digital processing applications.
pdficon AN9734 IEC Electromagnetic Compatibility Standards for Industrial Process Measurement and Control Equipment

This application note discusses the purpose of the International Electrotechnical Commission lEC 61000-4 (previously known as lEC-801) standard which established a common reference for evaluating the performance of industrial-process measurement and control instrumentation when exposed to electric or electromagnetic interference.
pdficon SP721 Series Datasheet

The SP721 is an array of SCR/Diode bipolar structures for ESD and over-voltage protection to sensitive input circuits...
pdficon SP720 SP721 and SP723 Turn-On and Turn-Off Characteristics Application Note

The purpose of this application note is to focus on customer concerns related to the fast switching characteristics of the SP720 SP721 and SP723 family of protection ICs during an ESD discharge. The SCR cell structures of this family were first introduced for ESD protection of sensitive ICs that were subject to substantially more severe conditions than normal Human Body Model stress.