User`s guide

Introduction LZ87010 Advance User’s Guide
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1.6.15 Reset
The RESET pin, when asserted HIGH, drives the entire device to a known state. Shortly
after RESET is released, execution proceeds from address 0 in the embedded Flash pro-
gram memory.
A watchdog timer, if enabled, will reset the chip after a period of inactivity.
1.6.16 Power and Ground
The LZ87010 is typically operated from a single 3.3 V supply. The device uses 2.5 V for
the core, provided by an on-chip voltage regulator.
Separate analog power and ground pins are provided to allow extra filtering on the board
for the analog power. The analog and digital supplies must be derived from the same
source to prevent latch-up.
1.6.17 Low-Power Modes
The LZ87010 has three operating modes: Active, Idle, and Stop. In Idle mode, the oscilla-
tors continue to run and the peripherals remain active, but the processor core halts until
an interrupt is received. In Stop mode, the oscillators are halted, the core and the periph-
erals halt, and operation can be resumed only by asserting RESET.
Power consumption is significantly reduced in low-power modes.
Further power savings can be obtained by disabling the internal voltage regulator (by tying
ENDC LOW) and using an external 2.5 V power supply on the VDD_CORE pin.