MAX14856 Datasheet, PDF (1/22 Pages) Maxim Integrated Products – 5kVRMS Isolated 500kbps/25Mbps Full-Duplex

MAX14856/MAX14858
EVALUATION KIT AVAILABLE
5kV_RMS Isolated 500kbps/25Mbps Full-Duplex
RS-485/RS-422 Transceivers
with ±35kV ESD Protection
General Description
The MAX14856/MAX14858 isolated RS-485/RS-422
transceivers provide 5000V_RMS (60s) of galvanic
isolation between the cable side (RS-485/RS-422 driver/
receiver-side) and the UART side of the device. Isolation
improves communication by breaking ground loops and
reduces noise when there are large differences in ground
potential between ports. These devices allow for robust
communication up to 500kbps (MAX14856) or 25Mbps
(MAX14858).
The devices include one drive channel and one receive
channel. The receiver is 1/4-unit load, allowing up to 128
transceivers on a common bus.
Integrated true fail-safe circuitry ensures a logic-high on the
receiver output when inputs are shorted or open. Undervoltage
lockout disables the driver when the cable side or UART side
power supplies are below functional levels.
The driver outputs and receiver inputs are protected
from ±35kV electrostatic discharge (ESD) to GNDB on
the cable side, as specified by the Human Body Model
(HBM).
The devices are available in a wide-body 16-pin
SOIC package and operate over the -40°C to +105°C
temperature range.
Functional Diagram
VDDA
VLDO
MAX14856
MAX14858
LDO
VDDB
SBA
RXD
A
RE
B
TXD
Z
Y
DE
Benefits and Features
●● High-Performance Transceiver Enables Flexible Designs
• Integrated LDO for Cable Side Power
• Compliant with RS-485 EIA/TIA-485 Standard
• 500kbps (MAX14856)/25Mbps (MAX14858)
Maximum Data Rate
• Allows Up to 128 Devices on the Bus
●● Integrated Protection Ensures for Robust
Communication
• ±35kV ESD (HBM) on Driver Outputs/Receiver Inputs
• 5kVRMS Withstand Isolation Voltage for 60
Seconds (VISO)
• 1200VPEAK Maximum Repetitive Peak-Isolation
Voltage (VIORM)
• 848VRMS Maximum Working-Isolation Voltage
(VIOWM)
• > 30 Years Lifetime at Rated Working Voltage
• Withstands ±10kV Surge per IEC 61000-4-5
• Thermal Shutdown
Safety Regulatory Approvals Pending
●● UL According to UL1577
●● cUL According to CSA Bulletin 5A
●● VDE 0884-10
Applications
●● Industrial Automation Equipment
●● Programmable Logic Controllers
●● HVAC
●● Power Meters
Ordering Information appears at end of data sheet.
GNDA
GNDB
19-7966; Rev 0; 11/15