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TVS Diode Arrays

SCR Diode Array for ESD and Transient Overvoltage Protection

SP724

The SP724 is a quad array of transient voltage clamping circuits designed

to suppress ESD and other transient over-voltage events. The SP724 is

used to help protect sensitive digital or analog input circuits on data,

signal, or control lines operating on power supplies up to 20VDC.

The SP724 is comprised of bipolar SCR/diode structures to protect up

to four independent lines by clamping transients of either polarity to the

power supply rails. The SP724 offers very low leakage (1nA Typical) and

low input capacitance (3pF Typical). Additionally, the SP724 is rated to

withstand the IEC 61000-4-2 ESD specification for both contact and air

discharge methods to level 4.

The SP724 is connected to the sensitive input line and its associated

power supply lines. Clamping action occurs during the transient pulse,

turning on the diode and fast triggering SCR structures when the voltage

on the input line exceeds one VBE threshold above the V+ supply (or

one VBE threshold below the V- supply). Therefore, the SP724 operation

is unaffected by poor power supply regulation or voltage fluctuations

within its operating range.

Features

• An Array of 4 SCR/Diode Pairs in 6-Lead SOT-23

• ESD Capability per HBM Standards

- IEC 61000-4-2, Direct Discharge . . . . . . . . . . . . . . . . . 8kV (Level 4)

- IEC 61000-4-2, Air Discharge . . . . . . . . . . . . . . . . . . 15kV (Level 4)

- MIL STD 3015.7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . >8kV

• Input Protection for Applications with Power Supplies Up to +20V

(Single-Ended Voltage), and ±10V (Differential Voltage)

• Peak Current Capability

• IEC 61000-4-5 (8/20µs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±3A

• Single Pulse, 100µs Pulse Width . . . . . . . . . . . . . . . . . . . . . . . ±2.2A

• Low Input Leakage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1nA Typical

• Low Input Capacitance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3pF Typical

Applications

• Microprocessor/Logic Input Protection

• Data Bus Protection

• Analog Device Input Protection

• Voltage Clamp

Functional Block Diagram

Ordering Information

Pinout

PART

Min. Order

Qty.

NUMBER

TEMP. RANGE

PACKAGE

PKG. NO.

P6.064

3000

SP724AHT

-40 to 105

Tape and Reel

12

3

654

SP724

(SOT-23)

TOP VIEW

NOTES:

1. The design of the SP724 SCR/Diode ESD Protection Arrays is

covered by Littelfuse patent 4567500.

2. The full ESD capability of the SP724 is achieved when wired in a

circuit that includes connection to both the V+ and V- pins. When

handling individual devices, follow proper procedures for

electrostatic discharge.

2

V+

V-

IN

3, 4 AND 6

IN

1

5