P89LPC915_916_917 NXP Semiconductors, P89LPC915_916_917 Datasheet - Page 53

• Manufacturer Part Number: P89LPC915_916_917
• Description: The P89LPC915/916/917 are single-chip microcontrollers, available in low-cost packages,based on a high performance processor architecture that executes instructions in two tofour clocks, six times the rate of standard 80C51 devices
• Manufacturer: NXP Semiconductors

NXP Semiconductors
9. A/D converter
P89LPC915_916_917_5
Product data sheet
8.28 User sector security bytes
9.1 General description
9.2 Features
There are eight User Sector Security Bytes on the P89LPC915/916/917. Each byte
corresponds to one sector. Please see the P89LPC915/916/917 User’s Manual for
additional details.
The P89LPC915/916/917 devices have a single 8-bit, 4-channel multiplexed
analog-to-digital converter with a DAC module. A block diagram of the A/D converter is
shown in
sample-and-hold circuit providing an input signal to one of two comparator inputs. The
control logic in combination with the SAR drives a digital-to-analog converter which
provides the other input to the comparator. The output of the comparator is fed to the
SAR.
I
I
I
I
I
I
I
I
I
I
Single 8-bit, 4-channel multiplexed input, successive approximation A/D converter.
Four A/D result registers.
Six operating modes:
Three conversion start modes:
8-bit conversion time of 3.9 s at an A/D 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.
N
N
N
N
N
N
N
N
N
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.
Timer triggered start.
Start immediately.
Edge triggered.
Figure
22. The A/D consists of a 4-input multiplexer which feeds a
Rev. 05 — 15 December 2009
8-bit microcontrollers with accelerated two-clock 80C51 core
P89LPC915/916/917
© NXP B.V. 2009. All rights reserved.
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