P89LPC9401FBD NXP Semiconductors, P89LPC9401FBD Datasheet - Page 23

• Manufacturer Part Number: P89LPC9401FBD
• Description: IC, MCU 8BIT 80C51, LCD DRIVER, SMD
• Manufacturer: NXP Semiconductors

Specifications of P89LPC9401FBD

• Controller Family/series: (8051) 8052
• Core Size: 8bit
• No. Of I/o's: 23
• Program Memory Size: 8KB
• Ram Memory Size: 256Byte
• Cpu Speed: 18MHz
• Oscillator Type: External, Internal
• No. Of Timers: 4
• No.: RoHS Compliant

Philips Semiconductors
P89LPC9401_1
Preliminary data sheet
7.13.3 Additional port features
7.14.1 Brownout detection
7.14.2 Power-on detection
7.14 Power monitoring functions
7.15 Power reduction modes
After power-up, all pins are in Input-Only mode. Please note that this is different from
the LPC76x series of devices.
Every output on the P89LPC9401 has been designed to sink typical LED drive current.
However, there is a maximum total output current for all ports which must not be
exceeded. Please refer to
specifications.
All ports pins that can function as an output have slew rate controlled outputs to limit noise
generated by quickly switching output signals. The slew rate is factory-set to
approximately 10 ns rise and fall times.
The P89LPC9401 incorporates power monitoring functions designed to prevent incorrect
operation during initial power-up and power loss or reduction during operation. This is
accomplished with two hardware functions: Power-on detect and Brownout detect.
The Brownout detect function determines if the power supply voltage drops below a
certain level. The default operation is for a Brownout detection to cause a processor reset,
however it may alternatively be configured to generate an interrupt.
Brownout detection may be enabled or disabled in software.
If Brownout detection is enabled the brownout condition occurs when V
brownout trip voltage, V
when V
that can be below 2.7 V, BOE should be left in the unprogrammed state so that the device
can operate at 2.4 V, otherwise continuous brownout reset may prevent the device from
operating.
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, before the power supply voltage reaches a level where
Brownout detect can work. 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 P89LPC9401 supports three different power reduction modes. These modes are Idle
mode, Power-down mode, and total Power-down mode.
•
•
After power-up, all I/O pins except P1.5, may be configured by software.
Pin P1.5 is input only. Pins P1.2 and P1.3 and are configurable for either input-only or
open-drain.
DD
rises above V
Table 11 “Static electrical characteristics”
8-bit two-clock 80C51 microcontroller with 32 segment
Rev. 01 — 5 September 2005
bo
bo
(see
. If the P89LPC9401 device is to operate with a power supply
Table 11 “Static electrical characteristics”
Table 11 “Static electrical
DD
rise and fall times must be observed.
for specifications.
characteristics”), and is negated
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
P89LPC9401
for detailed
DD
falls below the
4 LCD driver
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