Op amps achieve breakthrough noise immunity

Op amps achieve breakthrough noise immunity
New Products |
Improves reliability and reduces design production-hours in a wide range of applications, including anomaly detection systems.
By Jean-Pierre Joosting


ROHM developed the BD8758xY series (BD87581YG-C, BD87582YFVM-C) of rail-to-rail input/output high-speed CMOS op amps. The devices feature an improved EMI immunity for automotive and industrial equipment applications requiring high-speed sensing in harsh environments, such as vehicle engine control units and anomaly detection systems for factory automation equipment.

Figure 1: BD87581YG-C, BD87582YFVM-C of rail-to-rail input/output high-speed CMOS op amps.

In recent years, advancements in electrification and mounting density have increased the amount of environmental noise in electric vehicles and cars equipped with ADAS. Generally, however, it is extremely difficult to carry out noise evaluation on individual boards and systems during automotive development. Therefore, it has to be performed after assembly. Moreover, some results require improvements such as large-scale EMI countermeasures to lower noise.

In response, ROHM released the EMARMOUR™ series in 2017 that have since been well received in the automotive and industrial markets due to their superior noise immunity that reduces design resources required by combining a vertically integrated production system with proprietary analog design technology.

The EMARMOUR™ series is designed to prevent malfunctions due to noise without the need to take special application measures. The latest BD8758xY series in particular, has demonstrated superior performance under four international noise evaluation tests. For example, in ISO 11452-2 radio wave emission testing conducted by vehicle manufacturers, the output voltage of standard products fluctuates by more than ±300 mV in all frequency bands, while the new BD8758xY series achieves ±10 mV or less. At the same time, the CMOS element structure enables accurate, high-speed signal amplification – without being affected by external noise when installed inside the targeted sensor applications. This significantly improves reliability while reducing design production-hours in a wide range of applications, including anomaly detection systems.

In addition, ROHM Real Model, a new high accuracy SPICE model that matches the electrical and temperature characteristics of the actual IC and simulation values to prevent rework after prototyping, is available on ROHM’s website.

Figure 2: Op-amp development concept.

Figure 3: Noise evaluation results.

Application examples include

  • EV/HEV inverters, engine control units, eCall (vehicle emergency call system), car navigation/air conditioning systems.
  • Industrial factory automation equipment, measurement equipment, measuring instruments, servo systems, and sensor systems and other automotive/industrial applications sensitive to noise.

Figure 4: Automotive-grade EMARMOUR™ op amps.

Figure 5: Automotive-grade EMARMOUR™ comparators.


Linked Articles
eeNews Embedded