Datasheet

ManualsBrandsSTMICROELECTRONICS ManualsDiodesCLT3-4BT6-TR

November 2007 Rev 5 1/13

CLT3-4B

Current limited over-voltage protected quad digital termination

Features

■ 4 channel topology

■ Wide range input dc Voltage:

–V

= - 0.3 to 30 V with R

= 0

–V

= - 30 to 30 V with R

= 1.8 kΩ

– Low side configuration with common

ground

■ Current limiter:

–I

GEN

= 3 mA

– Input current limiter activation voltage < 5 V

– Temperature compensated operation

■ Opto-coupler drive:

– No coupler activation below 1.5 mA input

current

■ Input protection (R

= 1.2 kΩ):

– IEC 61000-4-2 electrostatic discharge

ESD, Class 3

In contact, ± 6 kV; in air, ± 8 kV

Level B: temporary disruption; no

change of opto-coupler state

– IEC 61000-4-5 voltage surge, Class 3

± 1000 V with 42 Ω serial resistor in

differential mode

Level B: temporary disruption

– IEC 61000-4-4 transient burst immunity

± 4 kV peak voltage; 5 kHz repetitive

rate

Level A: fully functional

■ Operating ambient temperature: - 25 to 85° C

Benefits

■ Reduced overall dissipation

■ Compact with high integration

■ Enables input to meet type 1 and 3

characteristic of IEC 61131-2 standard

■ Compatible operation with 2 and 3 wires

proximity sensor according EN60947-5-2

standard

■ Insensitive to the on state sensor impedance

■ Surface mount package for highly automated

assembly

■ Enhanced functional reliability

Applications

■ Industrial automation

■ Programmable logic controller

■ Communication field bus nodes

■ Peripheral input / output modules

■ Machine tool interface

Description

The CLT3-4 is a quadruple input digital

termination device designed for 24 V dc

automation applications. It provides the front-end

circuitry of a digital input module (I/O) in industrial

automation, and drives an isolating opto-coupler.

Figure 1. Pin configuration

TSSOP20

COM

ESD

OUT

COM

12345678910

11121314151617181920

COMESD

ESD

The pins ESD, COM

, COM (pins # 1, 3, 6, 8, 10, 11,

13, 15, 16, 18, 20) must be connected together

externally. This common pad COM is enlarged to

reduce the thermal resistance and improve the device

cooling. The COM and IN pins are designed to

minimize the EMI effects on the circuit.

www.st.com

Summary of content (13 pages)

PAGE 1
CLT3-4B Current limited over-voltage protected quad digital termination Features ■ ■ ■ ■ ■ ■ 4 channel topology Wide range input dc Voltage: – VI= - 0.3 to 30 V with RI = 0 – VI = - 30 to 30 V with RI = 1.8 kΩ – Low side configuration with common ground Current limiter: – IGEN = 3 mA – Input current limiter activation voltage < 5 V – Temperature compensated operation Opto-coupler drive: – No coupler activation below 1.5 mA input current Input protection (RI = 1.
PAGE 2
Characteristics 1 CLT3-4B Characteristics Figure 2. Functional block diagram OPTO COUPLER DRIVER OUT1 IN1 I1 0.75xILIM ESD OVER VOLTAGE PROTECTION I1 0.25xILIM CURRENT LIMITER ILIM 1.5mA ESD12 COM12 ESD OVER VOLTAGE PROTECTION CURRENT LIMITER ILIM 1.5mA 0.25xILIM I2 0.75xILIM I2 IN2 OUT2 OPTO COUPLER DRIVER Vc BIASING CIRCUIT ESD Volt Prot TO COMPARATORS COM ESDC OPTO COUPLER DRIVER IN3 OUT3 I3 0.75xILIM I3 0.25xILIM ESD OVER VOLTAGE PROTECTION CURRENT LIMITER ILIM 1.
PAGE 3
CLT3-4B Characteristics Table 2. Thermal resistance Symbol Rth(j-a) Table 3. Symbol Parameter Value Unit 90 °C/W TSSOP20 thermal resistance junction to ambient Board copper surface = 2 cm2, copper thickness = 35 µm Electrical characteristics (TJ = 25 °C, VCC = 24 V and COM pin voltage referred unless otherwise specified) Pin Name Conditions Min. Typ Max. Unit 2.1 3 3.7 mA Current limitation ILIM IN Input limiting current VOUT = 0.9 to 2.
PAGE 4
Characteristics Table 5. Symbol VPP CLT3-4B CLT3 System electromagnetic compatibility ratings, RI = 1.8 kΩ, RC = 4.
PAGE 5
CLT3-4B Characteristics The current limiting circuit connected between the input and the output pins is compensated all over the temperature range. Thanks to its low tolerance, the current limitation allows reducing drastically the dissipation of the input compared to a resistive input: the overall module requires less cooling capability and becomes smaller. The output block of each termination channel controls the operation of an opto-coupler that is enabled by a Light Emitting Diode.
PAGE 6
Characteristics Figure 5. CLT3-4B Typical current limiter variation versus junction temperature 0.9 V < VOUT < 2 V Figure 6. IIim / IIim (25° C) 3.6 102% Typical limiter threshold voltage variation versus junction temperature for IIN = 2.1 mA VTH (V) 100% VIN = 27 V 98% 3.5 96% 94% 3.4 92% VIN = 5 V 90% 3.3 88% 86% Tj (° C) Tj (°C) 3.2 84% -25 0 25 50 75 100 125 -25 0 25 50 75 100 125 1.
PAGE 7
CLT3-4B Application information 2 Application information 2.1 Application description The CLT device is used between the input module and the opto-coupler of an I/O module. To secure the coupler off state and the non-conduction of its diode, the maximum CLT output current is 40 µA with R opto = 15 kΩ. When the CLT input voltage VIN is higher than 5 V, a minimum CLT output current of 1.5 mA will secure the opto-coupler on state. The CLT limiter is insensitive to the output voltage up to 2.0V.
PAGE 8
Application information CLT3-4B The CLT3-4 and the 24 V bus power supply have the same ground COM = GND. The reverse polarity of the power supply will shutdown the device. And the power supply resistor RC will limit the default current protecting the power supply pin VC. Its dissipation will be less than 0.2 W. Then, the whole module supply voltage rating is extended to from 0 to 30 V to -30 to +30 V. 2.
PAGE 9
CLT3-4B Application information Figure 10. Current sharing in the CLT device when IN4 is biased at - 30 V and the others at + 30 V, RI = 1.8 kΩ 0.8 mA Vcc = + 30 V 4.7 k Ω INN VCL= 38 V 3.7 mA I1 = + 30 V VC IREG N OUT1 1.8 kΩ OPTO N GND (0 V) COM OPTO 4 1.8 kΩ I2 = -30 - V 16.2 mA IN4 IREG4 OUT2 CLT3 - 4 Figure 11.
PAGE 10
Application information CLT3-4B Depending on the input type operation the input resistance RI can be adjusted because of the different on-state threshold VON MIN. So the surge voltage is also increased from the minimum level of the type 3 to the type as shown in Table 6. Table 6. Setting the input resistor RI according to the input type operation Type VON MIN (V) RI (kΩ) VPP surge (kV) 1 15 2.2 2 3 11 1.2 to 1.
PAGE 11
CLT3-4B 3 Package information Package information ● Epoxy meets UL94,V0 In order to meet environmental requirements, ST offers these devices in ECOPACK® packages. These packages have a lead-free second level interconnect. The category of second level interconnect is marked on the package and on the inner box label, in compliance with JEDEC Standard JESD97. The maximum ratings related to soldering conditions are also marked on the inner box label. ECOPACK is an ST trademark.
PAGE 12
Ordering information 4 Ordering information Table 8. 5 CLT3-4B Ordering information Order code Marking Package Weight Base qty Delivery mode CLT3-4BT6 CLT3-4B TSSOP20 0.074 g 74 Tube CLT3-4BT6-TR CLT3-4B TSSOP20 0.074 g 2500 Tape and reel Revision history Table 9. Document revision history Date Revision August-2002 4A 27-Nov-2007 12/13 5 Changes Previous release. Reformatted and restructured to current standard.
PAGE 13
CLT3-4B Please Read Carefully: Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale.