Si838x Data Sheet
Bipolar Digital Field Inputs for PLCs and Industrial I/O Modules
The Si838x provides eight input channels ideal for 24 V digital logic commonly used for
industrial applications. These channels can either sink or source current and feature in-
tegrated safety rated isolation. In combination with a few external components, this pro-
vides compliance to IEC 61131-2 switch types 1, 2, or 3. The input interface is based on
Silicon Labs' ground-breaking CMOS based LED emulator technology which enables
the bipolar capability (sinking or sourcing inputs) with no VDD required on the field side.
The output interface from the Si838x device allows for low power operation with 2.25 V
compliance. These products utilize Silicon Labs' proprietary CMOS-based isolation tech-
nology, supporting up to 2.5 kVRMS withstand voltage. This technology enables high
CMTI (up to 300 kV/μs), lower propagation delays and channel skew, reduced variation
with temperature and age, and tighter part-to-part matching. The Si838x offers longer
service life and dramatically higher reliability compared to opto-coupled input solutions.
Product options include parallel or serialized outputs. Parallel outputs can be purchased
with built-in, low-pass filters for improved noise immunity, reduced design complexity
and cost. Cascading a total of 128 channels (16x Si838x) with a single MCU interface is
possible with the Si8380S serial output option. The Si8380S also unlocks the ability to
configure each channel with unique filtering behavior.
Applications:
• Programmable logic controllers
• Industrial data acquisition
• Distributed control systems
• CNC machines
• I/O modules
• Motion control systems
Safety Regulatory Approvals:
• UL 1577 recognized
• Up to 2500 VRMS for one minute
• CSA component notice 5A approval
• IEC 60950-1
• IEC 62368-1
• VDE certification conformity
• VDE 0884-10
• CQC certification approval
• GB4943.1
KEY FEATURES
• Bipolar digital interface with 24 V sinking or
sourcing inputs
• Eight total inputs in one package
• High data rates of up to 2 Mbps
• Safety rated integrated isolation of 2.5
kVRMS
• Low input current of 1 mA typ
• No VDD required on field side
• High electromagnetic immunity
• Selectable debounce filter times of up to
100 ms
• Configurable debounce filter modes
available with SPI interface option
• Transient immunity up to 300 kV/μs
• Flow-through output configuration with
eight outputs
• Option for SPI interface with daisy-chain
capability
• Wide 2.25 to 5.5 V VDD operation
• Wide operating temperature range
• –40 to +125 °C
• Compliant to IEC 61131-2
• Type 1, 2, 3
• RoHS-compliant packages
• QSOP-20
A1 1
A2 2
A3 3
A4 4
COM 5
COM 6
A5 7
A6 8
A7 9
A8 10
e
e
e
e
e
e
e
e
Si8380P
20 B1
19 B2
18 B3
17 B4
16 VDD
15 GND
14 B5
13 B6
12 B7
11 B8
A1 1
A2 2
A3 3
A4 4
COM 5
COM 6
A5 7
A6 8
A7 9
A8 10
e
e
e
e
e
e
e
e
Si8380S
SPI
20 MISO
19 MOSI
18 NSS
17 SCLK
16 VDD
15 GND
14 MOSI_THRU
13 NC
12 NC
11 NC
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