TVS Diode Arrays
Electronic Protection Array for ESD and Overvoltage Protection
SP721
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 or
bus 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
+V BE diode threshold above V+ (Pin 8) or a -V BE 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 V BE above V+. A similar clamp to V- is activated if a negative pulse,
one V BE less than V-, is applied to an IN input. Standard ESD Human
Body Model (HBM) Capability is:
Pinout
Refer to Figure 1 and Table 1 for further detail. Refer to Application
Notes AN9304 and AN9612 for additional information.
Ordering Information
SP721AP
SP721AB
SP721ABT
IEC 61000-4-2
MIL-STD-3015.7 Direct, In-Circuit
234
PART NO.
STANDARD
HBM
TEMP. RANGE
IN
IN
IN
V-
-40 to 105
-40 to 105
-40 to 105
Air
Direct
Direct, Dual Pins
SP721 (PDIP, SOIC)
(
o
1
2
3
4
C)
MODE
TOP VIEW
8 Ld PDIP
8 Ld SOIC
8 Ld SOIC
Tape and Reel
PACKAGE
1.5kΩ
330Ω
330Ω
330Ω
R
8
7
6
5
V+
IN
IN
IN
150pF
150pF
150pF
100pF
C
M8.15
E8.3
M8.15
PKG.
NO.
ESD (V)
>15kV
>15kV
>4kV
>8kV
w w w . l i t t e l f u s e . c o m
Order
2000
1960
2500
Min.
Features
• ESD Interface Capability for HBM Standards
• High Peak Current Capability
• Designed to Provide Over-Voltage Protection
• Fast Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2ns Rise Time
• Low Input Leakages . . . . . . . . . . . . . . . . . . . . . . . . 1nA at 25
• Low Input Capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3pF Typical
• An Array of 6 SCR/Diode Pairs
• Operating Temperature Range . . . . . . . . . . . . . . . . . . . . -40
Applications
• Microprocessor/Logic Input Protection
• Data Bus Protection
• Analog Device Input Protection
• Voltage Clamp
Functional Block Diagram
- 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)
- IEC 61000-4-5 (8/20µs). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±3A
- Single Pulse, 100µs Pulse Width . . . . . . . . . . . . . . . . . . . . . . . . ±2A
- Single Pulse, 4µs Pulse Width . . . . . . . . . . . . . . . . . . . . . . . . . . ±5A
- Single-Ended Voltage Range to . . . . . . . . . . . . . . . . . . . . . . . . +30V
- Differential Voltage Range to. . . . . . . . . . . . . . . . . . . . . . . . . . . ±15V
V+
IN
V-
8
1
4
IN
2
IN
3, 5-7
o
C to 105
o
C Typical
o
C