OPF794 Optek, OPF794 Datasheet - Page 27

• Manufacturer Part Number: OPF794
• Description: Photodiodes Pin Photodiode
• Manufacturer: Optek

Specifications of OPF794

• Maximum Reverse Voltage: 100 V
• Maximum Rise Time: 6 ns
• Mounting Style: SMD/SMT
• Product: Photodiode
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Issue A.1 2005
OPTEK Technology Inc. www.optekinc.com
PhotoLogic
O
H
A
YSTERESIS
SSEMBLIES
PEN
Even with the numerous advantages of the totem-pole configuration the open-collector output configuration has its place in the
design world. With an open-collector output configuration the designer can configure one or more collector outputs into what is
referred to as collector logic or wired logic. This is simply the ability to form a logic function using the available collector outputs.
In this case the low output resistance for both the high and low output level of a totem-pole configuration is not desirable. The
ability to design with wired logic can save on the number of logic gates required in a system design resulting in a cost savings.
The Photologic® family incorporates a Schmitt trigger as part of the integrated circuit. The Schmitt trigger is a very useful circuit
in steering the leading and trailing edges of a slowly rising or falling pulse. An inherent characteristic of a Schmitt trigger circuit is
that a different input threshold level exists for a positive and negative signal. Hysteresis is the difference between the input
thresholds of the Schmitt trigger.
The hysteresis, or threshold window, of the Schmitt trigger provides immunity to small input signal variations that are not desired
on the output of the Photologic® circuit. The larger the difference between the input thresholds the greater the immunity to
noise or signal variations. The trade off is unfortunately speed or output response time.
The combination of Photologic® discrete components and the large selection of standard housings, mechanical configurations
and apertures provides the designer with literally hundreds of options available to address their application utilizing standard
products. OPTEK offers the designer a value added assembly by adding a wide variety of connectors to the standard assemblies.
Contact an OPTEK sales office for price and delivery of value added assemblies.
-C
OLLECTOR
®
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