SCLT3-8BT8 Datasheet, PDF (1/33 Pages) STMicroelectronics – Protected digital input termination with serialized state transfer

SCLT3-8BT8
Protected digital input termination with serialized state transfer
Features
■ 8-input circuit in common ground low side
topology
■ Wide range input DC voltage V_I : -30 V to 35 V
– On state threshold : < 11 V with R_I = 2.2 kΩ
– Off state threshold: I_in > 1.5 mA or V_i > 5 V
– Protected against -30 V reverse polarity
■ 2.35 mA active current limiter with 10%
tolerance
– Drastic dissipation reduction:
78 mW max. per input
■ Input digital filter with adjustable delay:
20 µs to 3 ms
■ Energy-less LED visual status driver
■ Input logic state transfer through a 2 MHz SPI
– Programmable 8 / 16-bit register length
– Multi SCLT connection in daisy chain
– Chip temperature OTA and under voltage
UVA alarms
– Multi parity bits and power loss detection
with stop bits
– Drastic reduction of isolated coupler count
and I/O of the field bus ASIC
■ Power supply and input protection, R_I = 2.2 kΩ:
– IEC 61000-4-4 transient burst : ± 4 kV
minimum
– IEC 61000-4-5 voltage surge: ± 1 kV
minimum
– IEC 61000-4-2 ESD: ± 8 kV in contact:
± 15 kV in air minimum
■ Wide range power supply voltage V_C:
– + 9 V to + 35 V with 10 mA output current
– Protected against -30 V reverse polarity
SCLT3-8BT8
HTSSOP-38
Applications
■ Digital inputs for programmable logic controller
and decentralized I/O modules
■ Digital input with serialized state transfer
■ Enabling digital inputs to meet type 1 and 3
characteristics of IEC 61131-2
■ EN60947-5-2 2-wire proximity sensor
compatibility
Description
The SCLT3-8BT8 provides an 8-line protected
digital input termination with serialized state
transfer. This device enhances the I/O module
density by cutting the dissipation (78 mW per
input) and reducing the count of opto-transistors.
An adjustable digital filter and an LED driver are
embedded in each type 3 input section. Its 2 MHz
SPI peripheral output serializes the input state
transfer to the I/O module controller.
November 2009
Doc ID 15191 Rev 3
1/33
www.st.com
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