Rad Tolerant 3.3-V CAN Transceivers for Satellite Communications

Intersil Corp. recently announced  the industry’s first radiation-tolerant, 3.3-V controller area network (CAN) transceivers that are fully QML-V qualified and compliant with the ISO11898-2 physical layer standard. The three new ISL7202xSEH CAN transceivers provide reliable serial data transmission between a CAN controller and CAN bus at speeds up to 1 Mbps. Up to 120 of Intersil’s ISL7202xSEH transceivers can be connected to a single CAN bus to reduce cabling/harness size, weight and power (SWAP) costs. This weight and mass reduction of up to 18% allows system engineers to add millions of dollars in satellite functionality, and eliminate the extra cabling and tradeoffs associated with current point-to-point interface solutions.isl7202 Intersil

The ISL72026SEH, ISL72027SEH, and ISL72028SEH 3.3-V CAN transceivers deliver ultra-high performance in the most demanding environments by leveraging Intersil’s proprietary silicon on insulator process, which provides single event latch-up (SEL) and single event burn-out (SEB) robustness in heavy ion environments. With the emergence of all-electric propulsion satellites that maximize payload but take longer to reach final orbit, customers require higher total dose testing for mission assurance. Intersil’s CAN transceivers are low dose rate tested up to 75 krad on a wafer-by-wafer basis, and apply single event transient (SET) mitigation techniques to reduce system level bit error rates, providing predictable performance. They are also “cold spare” redundant capable, allowing the connection of additional unpowered transceivers to the CAN bus. This mission-critical capability maximizes system life.

  • The ISL7202xSEH family offers a number of unique features:
  • The ISL72026SEH includes a loopback test capability that allows node diagnostics and reporting while the system is transmitting data

It offers split termination output using the VREF pin to provide a VCC/2 output reference. This improves network electromagnetic compatibility and stabilizes the bus voltage, preventing it from drifting to a high common-mode voltage during inactive periods. The ISL72028SEH includes a low power shutdown mode that switches off the driver and receiver to draw 50 µA for power conservation.

Key features and specs:

  • Electrically screened to SMD 5962-15228, and compatible with ISO11898-2
  • Delivers 4-kV human body model (HBM) ESD protection on all pins
  • 3- to 3.6-V supply range, –7 to 12 V common-mode input voltage range, 5-V tolerant logic inputs, and bus pin fault protection to ±20-V terrestrial and ±18 V in orbit
  • Cold spare powered down devices do not affect active devices operating in parallel
  • Three selectable driver rise and fall times
  • Glitch free bus I/O during power-up and power-down
  • Full fail-safe receiver: open, short, terminated/undriven
  • Hi Z input allows for 120 nodes on the bus and data rates up to 1 Mbps
  • Low quiescent supply current of 7 mA
  • Thermal shutdown
  • Low dose rate (0.01 rad(Si)/s) radiation tolerance of 75 krad(Si)
  • SEL/B immune up to LET 60 MeV.cm2/mg

The ISL72026SEH, ISL72027SEH and ISL72028SEH 3.3V CAN transceivers are available in eight-lead ceramic flatpack packages.

Source: Intersil Corp.

High Efficiency, Highly Integrated 8A and 3A Synchronous Buck Regulators

Intersil Corp. recently announced five new highly integrated synchronous buck regulators that step-down 5-V rails to point-of-load (POL) inputs as low as 0.6 V for FPGAs, DSPs, and microprocessors. The ISL8018 delivers up to 8 A of continuous output current from a 2.7-to-5.5-V input supply. In addition, it provides up to 97% efficiency and higher integration than similar devices.

The ISL8003x devices deliver up to 3 A of continuous output current from a 2.7-to-5.5-V input supply and offer up to 95% peak efficiency for delivering general POL conversions. Useful in telecom, cloud computing, industrial, and medical equipment, the ISL8018 provides an innovative SYNCIN and SYNCOUT feature that connects and synchronizes multiple regulators at the same switching frequency in a master/slave configuration using a phase shifting time delay. With the ISL8018’s VSET feature, the voltage output margining can be set at 10% to compensate for output voltage IR drop. The ISET feature provides programmable output current limits to support 8-, 5-, and 3-A applications. This allows customers to leverage one design with smaller inductors for reduced costs and board area. In addition, the ISL8018’s programmable switching frequency from 500 kHz up to 4 MHz enables the use of smaller passive components for faster transient response and further board space savings.

Key features and specifications:

  • High peak efficiency up to 97%
  • Converter occupies less than 97 mm2 of board space
  • ±10% output voltage margining
  • Output voltage is adjustable from 0.6 V to Vin, with a fixed output voltage option
  • External synchronization up to 4MHz, with master-to-slave phase shifting capability
  • Adjustable switching frequency from 500 kHz to 4 MHz, with default at 1 MHz
  • Start-up with pre-bias output, internal soft-start—1 ms or adjustable, internal/external compensation
  • Soft-stop output discharge during disabled
  • Peak current limiting, hiccup mode short circuit protection, and over-temperature protection
  • Adjustable current limit

The ISL8018 8A synchronous buck regulator is available in a 3 mm × 4 mm, 20-lead QFN package and it costs $1.60 in 1,000-piece quantities. The ISL8018DEMO1Z demonstration board costs $20. The full-featured ISL8018EVAL3Z evaluation board is $115.

Source: Intersil Corp.

New Radiation Hardened Multiplexers for Space Flight Data Acquisition Systems

Intersil Corp. recently launched the ISL71840SEH and ISL71841SEH, new radiation hardened (rad hard) multiplexers that offer ESD protection and high signal chain accuracy and timing performance. The ISL71840SEH 30V 16-channel multiplexer is a drop-in replacement for Intersil’s HS9-1840ARH, which has been aboard nearly every satellite and space exploration mission (e.g., NASA’s Orion flight test). For applications with form factor constraints, the ISL71841SEH offers high performance and 41% reduced board space compared with an ISL71840SEH two-chip solution.ISL71840-Intersil

Both the ISL71840SEH and ISL71841SEH offer per-switch over-voltage protection. When an input channel experiences over-voltage, the remaining channels continue sending data to the ADC. Both multiplexers provide a “cold spare” redundant capability, which enables the connection of two or three additional unpowered multiplexers to a common data bus. If needed, a redundant multiplexer is immediately activated. Both multiplexers provide a wide supply range with split-rail operation from ±10.8 V to 16.5 V and an absolute maximum of ±20 V.

Source: Intersil Corp.