STMicroelectronics STM65xx Smart-Reset Chip Family

STMicroelectronics introduced the STM6502, STM6503, STM6504, and STM6505 smart-reset chips. The STM65xx family of smart-reset Integrated Circuits (IC) enables the system to be restarted safely without removing the battery or finding a tool to push the reset button, usually hidden behind a hole in the casing. ST’s smart reset solution simplifies design, reduces part count, and saves on overall system cost while improving the industrial design. The STM65xx is in mass production now and is priced at $0.53 for 10,000 units.

STMicroelectronics STM65xx Smart-Reset IC Features

  • Operating voltage 1.0 V (active-low output valid) to 5.5 V
  • Low supply current
  • Factory-programmable thresholds to monitor VCC in the range of 1.575 to 4.625 Vtyp
  • Open-drain, active-low reset output
  • Dual smart reset push-button inputs with extended reset set up delay
  • Adjustable smart reset setup delay (tSRC): by external capacitor or external resistor or three-state logic
  • Power-on reset
  • Operating temperature: industrial grade -40 °C to +85 °C
  • Package: TDFN-8L 2 x 2 x 0.75 mm, 0.5 mm pitch
  • RoHS compliant

STMicroelectronics’ STM65xx family of smart-reset Integrated Circuits (IC) has two inputs that can be connected to two of the device’s normal function buttons. When these are held down for a certain time, which is programmable, the IC will send a reset signal to the main processor. The two inputs and programmable delay time allow a combination of button presses and hold-down times to guard against unintended resets. While other ICs on the market can control one reset key, only the STM65xx has this smart-reset capability with two inputs and also includes the system-controlled supervision and reset features that most product designs require.

The chip provides a safe, convenient, and easily understood means of restarting those frozen gadgets. For manufacturers, combining an improved manual reset with the system-controlled reset functions in a single chip offers better performance and saves cost and pc-board space. Its 2 x 2 mm package has a smaller overall footprint than using separate chips for system reset and one-key manual reset, or an equivalent network of discrete components that can occupy as much as 100 sq-mm on the board.

In addition, by allowing the manual reset to be controlled from the normal user buttons, the STM65xx can enable product designers to eliminate the traditional hidden reset requiring an access hole in the casing. This can save tooling costs and also provides an opportunity to create splash-resistant or waterproof new products.

More info: STM6502, STM6503, STM6504, STM6505 Smart-Reset Chips (pdf)