PCA9622_12 Datasheet, PDF (14/39 Pages) NXP Semiconductors – 16-bit Fm+ I2C-bus 100 mA 40 V LED driver

NXP Semiconductors
PCA9622
16-bit Fm+ I²C-bus 100 mA 40 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
register).
Only the 7 MSBs representing the I²C-bus subaddress are valid. The LSB in SUBADRx
register is a read-only bit (0).
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
Table 12. ALLCALLADR - LED All Call I²C-bus address register (address 1Bh) bit
description
Legend: * default value.
Address Register
Bit Symbol Access Value
Description
1Bh
ALLCALLADR 7:1 AC[7:1] R/W 1110 000* ALLCALL I²C-bus
address register
0
AC[0] R only 0*
reserved
The LED All Call I²C-bus address allows all the PCA9622s 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 PCA9622
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.
PCA9622
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 4 — 6 September 2012
© NXP B.V. 2012. All rights reserved.
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