Low-cost circuit programs EEPROMs

摘要

When you migrate to 3.3V system supplies, you must usually replace your old, reliable EEPROM programmer with a new, overly flexible and expensive universal programmer. We could not find a 3.3V programmer for less than $1000. For less than $100, the circuit in Figure 1 extends the functional life of any 5V EEPROM programmer. You can apply the circuit to any bidirectional 5 to 3.3V level-translating application. The key to the circuit lies in choosing the correct logic families.