| ||Most applications use one or more of the following types of logic in their designs:
In a broad sense, these products compete with each other as they may be used in the same types of applications in electronic systems. However, differences in cost, performance, density, flexibility, ease of use, and time to market dictate how much they directly compete for particular applications. The table below summarizes key characteristics of ASICs, ASSPs, and PLDs.
- Application-specific integrated circuits (ASICs) – Often referred to as standard cells, ASICs are manufactured with custom designs created by the customer. As a result, each ASIC has a fixed function used by a single customer in a single application.
- Application-specific standard products (ASSPs) – ASSPs are standard devices that usually cannot be customized by the end user. In contrast to an ASIC, which is built for a single customer, an ASSP is built for a specific type of application targeted to a small number of customers. ASSPs are sometimes described as ASICs developed for multiple customers.
- PLDs – Unlike ASICs and ASSPs, PLDs are standard products that can be customized for a wide range of applications. As a result, PLDs are typically sold to hundreds or thousands of customers. This flexibility offers many advantages, including simple design changes, shorter design cycles, and lower development costs.
||Yes, by chip
||Yes, by end user
|RELATIVE TIME TO MARKET
|RELATIVE UNIT COST
||Moderate to high
|CUSTOMER'S DEVELOPMENT COST
PLDs vs. ASICs
In contrast to ASICs, PLD designs are programmed directly into the PLD. This means that the PLD is fully functional and verified when the design is completed, avoiding the lengthy and complex cycles required to verify and fabricate ASICs. This user programmability allows PLD customers to test and revise their designs quickly and with minimal development cost. In addition to these ease-of-use and time-to-market advantages, PLDs can be upgraded in the field, which allows customers to modify the PLD design after the electronic system has been shipped. These advantages, however, come at a cost. Programmability requires a larger die size, which typically translates into a higher per-unit cost when compared to ASICs. As a result, unit volume for PLDs is typically lower than for ASICs.
ASICs offer more optimized chip performance and lower per-unit costs than PLDs, which means that they are generally viewed as a more cost-effective option for large-volume, low-cost applications such as consumer electronics. However, they require high up-front costs for design, verification, and mask development, known as non-recurring engineering (NRE) costs, that make sense only for very high volumes. NRE costs for ASICs can range from the
hundreds of thousands to multi-million dollar costs. Some customers prototype with PLDs for their time-to-market benefits and then redesign to an ASIC to reduce costs as volume increases. While redesigns have always been part of the PLD business, we believe that three trends increasingly drive customers to use PLDs for their systems’ entire life cycle:
- Lower price premiums for PLDs compared to ASICs
- Shorter life cycles of many electronic systems
- Increased failure risk and higher NRE costs of ASICs
PLDs vs. ASSPs
Customers use ASSPs when they need specific fixed functions with little differentiation, for example when implementing certain electronic industry standards. However, ASSPs have fixed functionality, which limits the range of applications they can address. In contrast to ASSPs, PLD flexibility allows customers to define functionality to suit their needs, rather than restrict their system architecture based on ASSP manufacturer specifications. Furthermore,
PLD designers can add IP design blocks to execute standardized functions otherwise performed by ASSPs.