Key Features

•

4-channel Pulse Width Modulator (PWM) generator

— Configurable resolution 1 – 10 bits

•

4-channel, 8-bit Analog-to-Digital Converter

— 9.3 microseconds conversion time at 20 MHz

— 100% accelerated C51 CPU core runs at 6 clocks

per instruction

•

20 MHz maximum operating frequency 4.5 – 6.0V and

10 MHz maximum operating frequency 2.7 – 6.0V

•

Configurable brownout reset detector

•

On-chip serial communications interfaces

— UART

•

Five I/O pin modes, individually selectable for each pin

— Quasi bi-directional

— Push-pull output

— Open drain output

— Input

— Schmitt trigger input

•

Up to 18 pins usable for general purpose I/O

Low Power, Low System Cost

80C51 MCU with ADC and PWM

P87LPC768

As a member of the 51LPC microcontroller family, the 87LPC768

offers an 8-bit ADC with four multiplexed channels and an 8-bit

Pulse Width Modulator (PWM.) Further, the device provides 4K

of OTP code memory and 128 bytes of data SRAM, making it

suitable for high-level programming. The code memory is In-System

Programmable (ISP) through a serial interface. Other embedded

features that reduce the need for external components are brownout

detection, power-on reset and an on-chip RC oscillator that is very

stable over temperature and voltage.

The MCU core is fully compatible with the industry-standard C51

core, but features a 2X speed mode, where the CPU clock is divided

by 6 instead of 12. At 20 MHz, the 51LPC family devices provide

a throughput identical to a conventional C51 running at 40 MHz,

thus minimizing EMI and power consumption. The 87LPC768 is

manufactured in Philips Semiconductor’s low-power CMOS tech-

nology and is well suited for use in battery powered applications.

At 32kHz, the device consumes only 16µA and the operating volt-

age ranges from 2.7 – 6.0V (3.0 – 6.0V for analog peripherals). A

fixed-frequency oscillator running at 6 MHz can be used to clock

the device in applications that do not require the high accuracy of

a crystal. Regardless of the clock source used, the user can reduce

operating frequency down to as much 1/512 of the source frequen-

cy, allowing the user to optimize performance and power consump-

tion on-the-fly. Use of the on-chip power-on reset and oscillator

makes up to 18 I/O pins available to the user, leaving only two

non-I/O pins for connection to power and ground.

Because the P87LPC768 combines an embedded ADC and PWM,

it is especially useful in applications that include dynamic position-

ing, speed and temperature control. The PWM provides very

high flexibility since the output resolution can be configured to

any number of bits up to 10.

The device comes with extensive serial communication capabilities.

On-chip UART provides serial communications for RS-232 and

such as serial EEPROMs, other MCUs and a variety of peripheral

devices. These communications interfaced in combination with

the analog capabilities makes the 87LPC768 ideal for a variety of

sensor applications.

The P87LPC768 is available in 20-pin SOIC and PDIP packages

Ordering Information

Part Number

Temperature (C)

Package Description

Operating Frequency

P87LPC768BN

0 to +70

Plastic Dual In-Line [PDIP20]

All devices operate at

P87LPC768BD

0 to +70

Plastic Small Outline [SOIC20]

20MHz @ 4.5 to 6.0V

P87LPC768FN

–40 to +85

Plastic Dual In-Line [PDIP20]

10MHz @ 2.7 to 6.0V

P87LPC768FD

–40 to +85

Plastic Small Outline [SOIC20]