PCA9625 datasheet(14/33 Pages) NXP

14 / 33 page

PCA9625_2

Product data sheet

Rev. 02 — 15 January 2008

14 of 33

NXP Semiconductors

PCA9625

16-bit Fm+ I2C-bus 100 mA 24 V LED driver

Once subaddresses have been programmed to their right values, SUBx bits need to be

set to logic 1 in order to have the device acknowledging these addresses (MODE1

Only the 7 MSBs representing the I2C-bus subaddress are valid. The LSB in SUBADRx

When SUBx is set to logic 1, the corresponding I2C-bus subaddress can be used during

either an I2C-bus read or write sequence.

7.3.8 ALLCALLADR, LED All Call I2C-bus address

The LED All Call I2C-bus address allows all the PCA9625s on the bus to be programmed

at the same time (ALLCALL bit in register MODE1 must be equal to 1 (power-up default

state)). This address is programmable through the I2C-bus and can be used during either

an I2C-bus read or write sequence. The register address can also be programmed as a

Sub Call.

Only the 7 MSBs representing the All Call I2C-bus address are valid. The LSB in

ALLCALLADR register is a read-only bit (0).

If ALLCALL bit = 0, the device does not acknowledge the address programmed in register

ALLCALLADR.

7.4 Active LOW output enable input

The active LOW output enable (OE) pin, allows to enable or disable all the LED outputs at

the same time.

• When a LOW level is applied to OE pin, all the LED outputs are enabled.

• When a HIGH level is applied to OE pin, all the LED outputs are high-impedance.

The OE pin can be used as a synchronization signal to switch on/off several PCA9625

devices at the same time. This requires an external clock reference that provides blinking

period and the duty cycle.

The OE pin can also be used as an external dimming control signal. The frequency of the

external clock must be high enough not to be seen by the human eye, and the duty cycle

value determines the brightness of the LEDs.

Remark: Do not use OE as an external blinking control signal when internal global

blinking is selected (DMBLNK = 1, MODE2 register) since it will result in an undeﬁned

blinking pattern. Do not use OE as an external dimming control signal when internal global

dimming is selected (DMBLNK = 0, MODE2 register) since it will result in an undeﬁned

dimming pattern.

Table 12.

ALLCALLADR - LED All Call I2C-bus address register (address 1Bh) bit

description

Legend: * default value.

Address

Bit

Symbol

Access

Value

Description

1Bh

ALLCALLADR

7:1

AC[7:1]

R/W

1110 000*

ALLCALL I2C-bus

address register

AC[0]

R only

reserved

PCA9625 Datasheet(PDF) 14 Page - NXP Semiconductors

PCA9625 Datasheet(HTML) 14 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

Datasheet Download

Link URL