zl70271-72-73-74-88-product-preview-oct2008.pdf

SURGE PROTECTION DEVICES ZL70271/72/73/74/88
PRODUCT PREVIEW
The ZL70271, ZL70272, ZL70273, ZL70274 and ZL70288 form a family of high-performance surge protection devices for implantable medical electronics. Optimized
for fast turn-on and extremely low leakage current, the ICs ensure high performance and reliability, as well as an easy route to compliance with the EN-45502
and EN-50061 specifications. Zarlink’s family of surge protection devices includes
variants to support a range of application requirements for number of terminals
and operating voltage:
The ZL70274 and ZL70288 are seven-terminal devices for triple-chamber
pacemakers
The ZL70271 is a five-terminal devices for dual-chamber pacemakers
The ZL70273 is a six-terminal device optimized for size critical applications
The ZL70272 is a five-terminal device for neurostimulators
Enhanced Performance
Extremely fast turn on (ZL70271 is
<100ns)
Low differential peak voltage
Extremely low leakage allows
terminals to be connected in parallel
to the device it protects
Eases Design
Variants with 5, 6, or 7 terminals
support range of applications
requirements
Very small size supports trend for
miniaturization
Applications
Pacemakers
Implantable cardioverter
defibrillators (ICDs)
Neurostimulators
Bladder control devices
Packaging and Availability
Package: Solder bumped die
ZL70274/88
ZL70273
ZL70272
ZL70271
Performance Characteristics
Vfz*
min (V)
9.0
Vbo*
max (V)
12.2 19.5 12.2 12.2
Leakage
(nA)
150
Size
(mm2)
17.0
9.0
9.0
Sample Availability: Now
Superior Quality
QA procedures based on MILPRF-38535
Traceability for every chip to lot and
wafer number
100% burn-in capability
Standards Compliant
EN-45502
150
100
100
10.2 10.2
7.5
8.7
* See below, Ifz=10µA
EN-50061
Customer Support
Zarlink’s surge protection devices are
supported by a team of application
design engineers with extensive medical
system design experience.
ZL70271/72/73/74/88 SURGE PROTECTION DEVICES
APPLICATION
Implantable medical electronics, such as pacemakers, ICDs, neurostimulators and bladder control devices, are used to treat a
wide range of illnesses including bradycardia, tachycardia,
Parkinson’s disease, chronic pain, muscle spasticity and incontinence. To maintain reliability, these implantable devices must
be able to withstand electrical surges, such as those caused by
medical treatments like defibrillation.
The diagram shown below of a dual-chamber pacemaker demonstrates how the ZL70271 device protects sensitive circuitry
from transient currents. Designed with extremely low leakage
during normal pacing voltages, the terminals of the ZL70271
are connected in parallel with those of the protected pacemaker pins.
Surge suppression occurs through a self-triggering thyristor-diode, coupled with a diode between each branch-input
and common node. When a transient current is forced
between two terminals, the positive terminal is clamped
to the common node by the diode of one branch, and the
negative terminal to the forward voltage of the thyristordiode on the other branch. The low on-voltage of the
thyristor ensures that voltage remains at a safe value during
the transient.
Extremely fast turn-on and low leakage current eases compliance with regulations EN-45502 for active implantable medical
devices, and EN-50061 for implantable cardiac pacemakers.
When the voltage between the terminals rises to a dangerous
level, the device rapidly turns on and shunts the current.
Surge Protection Device
ZL70270/1
T1
T2
T3
T4
TYPICAL DUAL CHAMBER
PACEMAKER
T5
Analog Chip
Atrial tip lead
Charge
Pump
Atrial ring lead
Case
Ventricular tip lead
Digital
Chip
Stimulation
& Sensing
block
Ventricular ring lead
Voltage &
Current
Reference
Information relating to products and services furnished herein by Zarlink Semiconductor Inc. or its subsidiaries is believed to be reliable.
The products, their specifications, services and other information appearing in this publication are subject to change by Zarlink without notice.
ZARLINK, ZL, and the Zarlink logo are trademarks of Zarlink Semiconductor Inc.
© 2008, Zarlink Semiconductor Inc. All Rights Reserved. Publication Number 8ZS187
www.ZARLINK.com