2030-23T-SM-RPLF Bourns Inc., 2030-23T-SM-RPLF Datasheet - Page 3

• Manufacturer Part Number: 2030-23T-SM-RPLF
• Description: MINI TRIGARD SURFACE MOUNT GDT
• Manufacturer: Bourns Inc.
• Series: TRIGARD™ 2030r

Specifications of 2030-23T-SM-RPLF

• Termination Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

TBU-CA065-100-WH
2030-23T-SM-RPLF
CDSOT23-SM712
Implementing Advanced Circuit Protection Technologies for RS-485 Ports
Protection for RS-485 Ports
Single-stage protection usually consists of a single TVS device on each data line. A general
protection scheme for each node of an RS-485 network includes a TVS diode array such as the
CDSOT23-SM712 from Bourns. This provides the overvoltage protection for the RS-485 transceiver
across the entire -7 V to +12 V common-mode voltage range. For RS-485 systems with limited
exposure, this diode array may be all that is needed for reliable operation. However, many
RS-485 networks are deployed in environments where failure is not acceptable, repairs are difficult
or expensive, or the surge threats overpower this simple protection scheme.
For more exposed lines that may see large and fast surges, three-stage protection shown in
figure 1, is more suitable in its ability to withstand these conditions. It consists of TVS diodes, TBU™
devices, and one or more GDTs. The characteristics of these three technologies are complementary,
working together to provide protection to the RS-485 interface where they would lack if used
independently. The GDT can handle extremely high currents but has a high threshold voltage
and may not trigger in time. The TBU™ device has a small series impedance that limits current
and voltage to which the equipment is exposed. The GDT device protects the TBU™ device from
excessive voltage after the TBU™ device triggers. However, the GDT is too slow to protect against
ESD. Thus, the TVS diode is necessary to provide voltage suppression against ESD/EFT transients.
Understanding Bourns® TBU™ Device Operation
The TBU-CA Series of Bourns TBU™ products are low capacitance, single, bidirectional, high-speed
circuit protection components constructed with MOSFET semiconductor technology. They are
designed to protect against faults caused by short circuits, AC power cross, induction and lightning
surges up to rated limits, and reset once the fault clears. The TBU™ device offers a significant
performance increase in terms of response time. It is easy to place and route a TBU™ in a design
since the TBU-CA package measures a mere 6.5 mm by 4 mm. The TBU™ device is provided in a
surface mount DFN package and meets industry standard requirements such as RoHS and Pb Free
solder reflow profiles.
Figure 1: Three-Stage Protection Block Diagram
Equipment
Diodes
TVS
TBU
TBU
GDTs
Port