beautypg.com

Application design-in information, 1 specific applications, 2 add i2c-bus port – NXP Semiconductors PCA9665 User Manual

Page 67: Pca9665, Nxp semiconductors, 2 add i, C-bus port

background image

PCA9665_2

© NXP B.V. 2006. All rights reserved.

Product data sheet

Rev. 02 — 7 December 2006

67 of 91

NXP Semiconductors

PCA9665

Fm+ parallel bus to I

2

C-bus controller

10. Application design-in information

10.1 Specific applications

The PCA9665 is a parallel bus to I

2

C-bus controller that is designed to allow ‘smart’

devices to interface with I

2

C-bus or SMBus components, where the ‘smart’ device does

not have an integrated I

2

C-bus port and the designer does not want to ‘bit-bang’ the

I

2

C-bus port. The PCA9665 can also be used to add more I

2

C-bus ports to ‘smart’

devices, provide a higher frequency, lower voltage migration path for the PCF8584 and
convert 8 bits of parallel data to a serial bus to avoid running multiple traces across the
printed-circuit board.

10.2 Add I

2

C-bus port

As shown in

Figure 33

, the PCA9665 converts 8-bits of parallel data into a multiple master

capable I

2

C-bus port for microcontrollers, microprocessors, custom ASICs, DSPs, etc.,

that need to interface with I

2

C-bus or SMBus components.

Fig 32. Application diagram using the 80C51

002aab035

PCA9665

80C51

DECODER

D0 to D7

ALE

CE

RD

WR

INT

A0

SCL

SDA

A1

RESET

SLAVE

INT

RESET

address bus

V

DD

V

DD

8

V

SS

V

DD

V

DD

V

DD

V

SS

SLAVE