PSD413A2 datasheet(4/123 Pages) STMICROELECTRONICS

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Introduction

Programmable Peripheral

PSD4XX Family

Field-Programmable Microcontroller Peripherals

The PSD4XX family is a microcontroller peripheral that integrates high-performance and

user-configurable blocks of EPROM, programmable logic, and SRAM into one part.

The PSD4XX products also provide a powerful microcontroller interface that eliminates the

need for external “glue logic”. The no “glue logic” concept provides a user-programmable

interface to a variety of 8- and 16-bit (multiplexed or non-multiplexed) microcontrollers that

is easy to use. The part’s integration, small form factor, low power consumption, and ease

of use make it the ideal part for interfacing to virtually any microcontroller.

The PSD4XX provides two Zero-power PLDs (ZPLD): a Decode PLD (DPLD) and a

General-purpose PLD (GPLD). A configuration bit (Turbo) can be set by the MCU, and will

automatically place the ZPLDs into Standby Mode if no inputs are changing. The ZPLDs are

designed to consume minimum power using Zero-power CMOS technology that uses only

10 µA (typical) standby current. Unused product terms are automatically disabled, also

reducing power, regardless of the Turbo bit setting.

The main function of the DPLD is to perform address decoding for the internal I/O ports,

EPROM, and SRAM. The address decoding can be based on up to 24 bits of address

inputs, control signals (RD, WR, PSEN, etc.), and internal page logic. The DPLD supports

separate program and data spaces (for 8031 compatible MCUs).

The General-purpose PLD (GPLD) can be used to implement various logic functions

defined by the user, such as:

• State machines

• Loadable counters and shift registers

• Inter-processor mailbox

• External control logic (chip selects, output enables, etc.).

The GPLD has access to up to 59 inputs, 118 product terms, 24 macrocells, and 24 I/O

pins.

PSD413A2 Datasheet(PDF) 4 Page - STMicroelectronics