ESDA25B1 STMicroelectronics, ESDA25B1 Datasheet - Page 3

• Manufacturer Part Number: ESDA25B1
• Description: TRANSIL ARRAY ESD 25V 8-SOIC
• Manufacturer: STMicroelectronics
• Series: TRANSIL™r

Specifications of ESDA25B1

• Voltage - Reverse Standoff (typ): 24V
• Voltage - Breakdown: 25V
• Power (watts): 150W
• Polarization: 6 Channel Array - Bidirectional
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6688-5; ESDA25B1

CALCULATION OF THE CLAMPING VOLTAGE
USE OF THE DYNAMIC RESISTANCE
The ESDA family has been designed to clamp fast
spikes like ESD. Generally the PCB designers
need to calculate easily the clamping voltage V
This is why we give the dynamic resistance in
addition to the classical parameters. The voltage
across the protection cell can be calculated with
the following formula:
Where Ipp is the peak current through the ESDA cell.
DYNAMIC RESISTANCE MEASUREMENT
a more adapted test wave, as below defined, to the
classical 8/20 s and 10/1000 s surges.
I
Ipp
The short duration of the ESD has led us to prefer
2.5 s duration measurement wave.
V
CL
tp = 2.5µs
2µs
= V
BR
+ Rd I
PP
CL
t
.
As the value of the dynamic resistance remains
stable for a surge duration lower than 20 s, the
2.5 s rectangular surge is well adapted. In addition
both rise and fall times are optimized to avoid any
parasitic phenomenon during the measurement of
Rd.
ESDA25B1
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