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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

+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. Standard ESD Human

Body Model (HBM) Capability is:

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 Capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3pF Typical

• An Array of 6 SCR/Diode Pairs

Applications

• Microprocessor/Logic Input Protection

• Data Bus Protection

• Analog Device Input Protection

• Voltage Clamp

Functional Block Diagram

4

V+

V-

IN

3, 5-7

IN

IN

1

8

2

Refer to Figure 1 and Table 1 for further detail. Refer to Application

Notes AN9304 and AN9612 for additional information.

Pinout

SP721 (PDIP, SOIC)

TOP VIEW

HBM

STANDARD

MODE

R

C

ESD (V)

IEC 61000-4-2

Air

330Ω

150pF

>15kV

Direct

330Ω

150pF

>4kV

Direct, Dual Pins

330Ω

150pF

>8kV

MIL-STD-3015.7

Direct, In-Circuit

1.5kΩ

100pF

>15kV

Ordering Information

PART NO.

TEMP. RANGE

PACKAGE

PKG.

NO.

Min.

Order

SP721AP

-40 to 105

8 Ld PDIP

E8.3

2000

1960

2500

SP721AB

-40 to 105

8 Ld SOIC

M8.15

SP721ABT

-40 to 105

8 Ld SOIC

Tape and Reel

M8.15

IN

IN

IN

V-

1

2

3

4

8

7

6

5

V+

IN

IN

IN