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
鈥?An Array of 4 SCR/Diode Pairs in 6-Lead SOT-23
鈥?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
鈥?Input Protection for Applications with Power Supplies Up to +20V
(Single-Ended Voltage), and 鹵10V (Differential Voltage)
鈥?Peak Current Capability
鈥?IEC 61000-4-5 (8/20碌s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 鹵3A
鈥?Single Pulse, 100碌s Pulse Width . . . . . . . . . . . . . . . . . . . . . . . 鹵2.2A
鈥?Low Input Leakage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1nA Typical
鈥?Low Input Capacitance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3pF Typical
Ordering Information
PART
NUMBER
SP724AHT
TEMP. RANGE
(
o
C)
-40 to 105
PACKAGE
Tape and Reel
PKG. NO.
P6.064
Min. Order
Qty.
3000
Pinout
SP724
(SOT-23)
TOP VIEW
6
5
4
鈥?Operating Temperature Range . . . . . . . . . . . . . . . . . . . . -40
o
C to 105
o
C
Applications
鈥?Microprocessor/Logic Input Protection
鈥?Data Bus Protection
鈥?Analog Device Input Protection
鈥?Voltage Clamp
Functional Block Diagram
1
2
3
V+
5
3, 4 AND 6
IN
1
IN
V-
2
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.
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w w w. l i t t e l f u s e . c o m
LITTELFUSE
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