P89LPC980 NXP [NXP Semiconductors], P89LPC980 Datasheet - Page 42

• Manufacturer Part Number: P89LPC980
• Description: 8-bit microcontroller with accelerated two-clock 80C51 core, 4 kB/8 kB wide-voltage byte-erasable flash with 10-bit ADC
• Manufacturer: NXP [NXP Semiconductors]

NXP Semiconductors
P89LPC980_982_983_985_2
Preliminary data sheet
7.17.3.1 Idle mode
7.17.3.2 Power-down mode
7.17.3.3 Total Power-down mode
7.17.2 Power-on detection
7.17.3 Power reduction modes
7.17.4 Regulators
For correct activation of brownout detect, the V
Please see
The Power-on detect has a function similar to the brownout detect, but is designed to work
as power comes up initially to ensure that the device is reset from Power-on. The POF
flag in the RSTSRC register is set to indicate an initial power-up condition. The POF flag
will remain set until cleared by software.
The P89LPC980/982/983/985 supports three different power reduction modes. These
modes are Idle mode, Power-down mode, and total Power-down mode.
Idle mode leaves peripherals running in order to allow them to activate the processor
when an interrupt is generated. Any enabled interrupt source or reset may terminate Idle
mode.
The Power-down mode stops the oscillator in order to minimize power consumption.
Brownout detection circuitry is disabled. The P89LPC980/982/983/985 exits Power-down
mode via any reset, or certain interrupts.
Some chip functions continue to operate and draw power during Power-down mode,
increasing the total power used during power-down. These include: watchdog timer,
comparators and RTC/system timer (note that watchdog timer, comparators and
RTC/system timer can be powered down separately). The internal RC oscillator is
disabled unless both the RC oscillator has been selected as the system clock and the
RTC is enabled.
The total Power-down mode is a deeper power reduction mode. Brownout detection
circuitry and analog comparators are disabled, as well as the internal RC oscillator.
Please use an external low frequency clock or 25 KHz watchdog oscillator to achieve low
power with the RTC running during power-down.
Internal regulators can be adjusted automatically to minimize power consumption during
different power reduction modes. In normal or Idle modes, power consumption can be
further reduced by configuring PMUCON register.
In normal or Idle mode, regulators have two operation modes: high speed mode and low
current mode.
The regulators can be configured to low current mode to reduce the power consumption.
After power-on-reset, internal regulators enter into high speed mode as default. PMUCON
register is used to configure the regulators operation modes. If regulators switch from low
current mode to high speed mode, HCOK bit is used to indicate whether the switching is
ready. When set, it means switch successfully.
Table 13 “Static characteristics”
Rev. 02 — 8 February 2010
8-bit microcontroller with accelerated two-clock 80C51 core
P89LPC980/982/983/985
for specifications.
DD
rise and fall times must be observed.
© NXP B.V. 2010. All rights reserved.
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