89LPC925 datasheet(19/49 Pages) PHILIPS

19 / 49 page

Philips Semiconductors

P89LPC924/925

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

Product data

Rev. 03 — 15 December 2004

19 of 49

9397 750 14471

8.9.2

Features

• 8-bit, 4-channel multiplexed input, successive approximation A/D converter.

• Four result registers.

• Six operating modes

– Fixed channel, single conversion mode

– Fixed channel, continuous conversion mode

– Auto scan, single conversion mode

– Auto scan, continuous conversion mode

– Dual channel, continuous conversion mode

– Single step mode

• Three conversion start modes

– Timer triggered start

– Start immediately

– Edge triggered

• 8-bit conversion time of

≥ 3.9 µs at an ADC clock of 3.3 MHz

• Interrupt or polled operation

• Boundary limits interrupt

• DAC output to a port pin with high output impedance

• Clock divider

• Power down mode

8.9.3

A/D operating modes

Fixed channel, single conversion mode: A single input channel can be selected for

conversion. A single conversion will be performed and the result placed in the result

be generated after the conversion completes.

Fixed channel, continuous conversion mode: A single input channel can be

selected for continuous conversion. The results of the conversions will be sequentially

placed in the four result registers. An interrupt, if enabled, will be generated after

every four conversions. Additional conversion results will again cycle through the four

result registers, overwriting the previous results. Continuous conversions continue

until terminated by the user.

Auto scan, single conversion mode: Any combination of the four input channels

can be selected for conversion. A single conversion of each selected input will be

performed and the result placed in the result register which corresponds to the

selected input channel. An interrupt, if enabled, will be generated after all selected

channels have been converted. If only a single channel is selected this is equivalent

to single channel, single conversion mode.

Auto scan, continuous conversion mode: Any combination of the four input

channels can be selected for conversion. A conversion of each selected input will be

performed and the result placed in the result register which corresponds to the

selected input channel. An interrupt, if enabled, will be generated after all selected

89LPC925 Datasheet(PDF) 19 Page - NXP Semiconductors

89LPC925 Datasheet(HTML) 19 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49

Datasheet Download

Link URL