SH3000

SH3000 MicroBuddy™ Low-Power Programmable Multifunction Support IC for Microcontrollers SYSTEM MANAGEMENT Description The programmable SH3000 MicroBuddy™ (µBuddy™) provides all mandatory microcontroller support functions: ♦ CPU Supervisor ♦ Clock Management System ♦ Real Time Support ♦ Auxiliary functions Three components make a complete system: any microcontroller, the SH3000, and a bypass capacitor. This low-cost system would consume very little power and have clock-frequency accuracy of ±0.5%. A fourth component, a 32.768 kHz watch crystal, raises the clock frequency accuracy to ± 0.0256% (± 256 ppm). The SH3000 can operate completely stand-alone, or under control of the microcontroller. A single-wire interface handles both bi-directional communications and the interrupt / wake-up signal from the SH3000. The SH3000 stores all configuration, calibration, parameters, and status information in a 36-byte bank of control registers. On reset, most of these are reloaded with defaults from the factory-set One-Time-Programmable (OTP) memory. The microcontroller can change any settings on the fly. If some of the settings must remain fixed, a comprehensive set of write-protect bits is provided for several related groups of registers (with both permanent write-inhibit and lock/unlock capabilities). A backup power source may also be connected to the SH3000. The IC can directly accommodate 2/3-cell zinccarbon/alkaline, 2/3-cell mercury, 2/3/4-cell NiCd/NiMH, 1cell Li/Li+ batteries, or a super cap. Features ♦ ♦ Highly integrated IC - 3mm x 3mm x 0.9 mm 16-lead MLP (QFN) package CPU Supervisor - Low VDD reset programmable from 2.3 V to 4.3 V - Watchdog timer with programmable timeout periods - Both active-high and active-low reset outputs Clock Management System - Replaces High-Frequency (HF) crystal or resonator - Programmable clock output from 32 kHz to 16 MHz - Speed shift between multiple clock frequencies - Adjustable spectrum spreading for EMI reduction - Directly supports microcontroller STOP function - Deep sleep with instantaneous auto-wakeup Real Time Support - 179-year real time clock, battery backup capable - Dedicated 32 kHz buffered clock output - Built-in trim for 32.768 kHz oscillator to ± 4ppm - Programmable periodic interrupt / wakeup timer Auxiliary functions - 4-byte (32-bit) scratchpad RAM, loaded on reset with factory-set value (zero or optional ID code) - All settings programmable in real-time, defaults restored from OTP memory on reset Operates from 2.3 V to 5.5 V IDD