P89LPC9301(2009) View Datasheet(PDF) - NXP Semiconductors.

Part Name

Description

Manufacturer

P89LPC9301
(Rev.:2009)

8-bit microcontroller with accelerated two-clock 80C51 core 4 kB/8 kB 3 V byte-erasable flash

NXP Semiconductors. 

NXP Semiconductors

P89LPC9301/931A1

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

(P0.4) CIN1A

(P0.3) CIN1B

(P0.5) CMPREF

Vref(bg)

CP1

comparator 1

CO1

OE1

CN1

change detect

CMF1

CMP1 (P0.6)

(P0.2) CIN2A

(P0.1) CIN2B

CP2

comparator 2

change detect

CN2

CO2

OE2

Fig 13. Comparator input and output connections

CMF2

EC

CMP2 (P0.0)

002aae456

interrupt

7.25.1 Internal reference voltage

An internal reference voltage generator may supply a default reference when a single

comparator input pin is used. The value of the internal reference voltage, referred to as

Vref(bg), is 1.23 V ± 10 %.

7.25.2 Comparator interrupt

Each comparator has an interrupt flag contained in its configuration register. This flag is

set whenever the comparator output changes state. The flag may be polled by software or

may be used to generate an interrupt. The two comparators use one common interrupt

vector. If both comparators enable interrupts, after entering the interrupt service routine,

the user needs to read the flags to determine which comparator caused the interrupt.

7.25.3 Comparators and power reduction modes

Either or both comparators may remain enabled when Power-down or Idle mode is

activated, but both comparators are disabled automatically in Total Power-down mode.

If a comparator interrupt is enabled (except in Total Power-down mode), a change of the

comparator output state will generate an interrupt and wake-up the processor. If the

comparator output to a pin is enabled, the pin should be configured in the push-pull mode

in order to obtain fast switching times while in Power-down mode. The reason is that with

the oscillator stopped, the temporary strong pull-up that normally occurs during switching

on a quasi-bidirectional port pin does not take place.

Comparators consume power in Power-down and Idle modes, as well as in the normal

operating mode. This fact should be taken into account when system power consumption

is an issue. To minimize power consumption, the user can disable the comparators via

PCONA.5, or put the device in Total Power-down mode.

P89LPC9301_931A1_1

Preliminary data sheet

Rev. 01 — 9 April 2009

© NXP B.V. 2009. All rights reserved.

35 of 65

Share Link: