What is Trimming?

Analog ICs and SoCs include specifications in their circuit design that define the parameters for the input and output of analog signals. However, small physical shifts in manufacturing flow, such as foundry process shift or stress resulting from the packaging process, can cause the analog signal to shift from its target specification. This deviation must be corrected or compensated for in high-precision applications. For example, the brightness of the screen on a given model of mobile phone must be consistent across all the phones manufactured. Trimming helps compensate for shifts in screen brightness resulting from the production process and ensures that phones rolling of the final production line all display a similar level of screen brightness.

Embedded OTP eNVM from eMemory provides a small memory array for storing trimming information (Fig. 1) within the IC. Information recorded within the OTP eNVM can be used to precisely adjust the input or output signal of the analog device (Fig 2). This function can be executed on CP or FT level.

Applications

Benefits of Trimming with eMemory NVM

Traditional metal or poly fuse circuit can provide a fine tune function for these sensitive analog signals. (Figure 3) When engineers fine tune the analog signal by the traditional metal or poly fuse, a large current needs to be provided from external environment to internal adjusted points of IC and burn out the metal or poly line. The large current flow need to be arranged carefully or other circuit of the chip will be damaged by the large current. Some residue will be generated to contamination other circuits near metal of poly fuse. The final yield may be decreased.