P89LPC932A1 View Datasheet(PDF) - Philips Electronics

Part Name

Description

Manufacturer

P89LPC932A1

8-bit microcontroller with accelerated two-clock 80C51 core 8 kB 3 V byte-erasable flash with 512-byte data EEPROM

Philips Electronics 

Philips Semiconductors

P89LPC932A1

8-bit microcontroller with accelerated two-clock 80C51 core

7.13.1.4 Push-pull output configuration

The push-pull output configuration has the same pull-down structure as both the

open-drain and the quasi-bidirectional output modes, but provides a continuous strong

pull-up when the port latch contains a logic 1. The push-pull mode may be used when

more source current is needed from a port output. A push-pull port pin has a Schmitt

trigger input that also has a glitch suppression circuit.

7.13.2 Port 0 analog functions

The P89LPC932A1 incorporates two Analog Comparators. In order to give the best

analog function performance and to minimize power consumption, pins that are being

used for analog functions must have the digital outputs and digital inputs disabled.

Digital outputs are disabled by putting the port output into the Input-only (high-impedance)

mode.

Digital inputs on Port 0 may be disabled through the use of the PT0AD register, bits 1:5.

On any reset, PT0AD[1:5] defaults to logic 0s to enable digital functions.

7.13.3 Additional port features

After power-up, all pins are in Input-only mode. Please note that this is different from

the LPC76x series of devices.

• 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.

Every output on the P89LPC932A1 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 Table 9 “Static characteristics” for detailed 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.

7.14 Power monitoring functions

The P89LPC932A1 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.

7.14.1 Brownout detection

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 the brownout condition occurs when VDD falls below the brownout

trip voltage, Vbo (see Table 9 “Static characteristics”), and is negated when VDD rises

above Vbo. If the P89LPC932A1 device is to operate with a power supply 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.

9397 750 14871

Product data sheet

Rev. 02 — 10 May 2005

© Koninklijke Philips Electronics N.V. 2005. All rights reserved.

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