pca9685 NXP Semiconductors, pca9685 Datasheet - Page 2

• Manufacturer Part Number: pca9685
• Description: 16-channel, 12-bit Pwm Fm+ I 2c-bus Led Controller
• Manufacturer: NXP Semiconductors

NXP Semiconductors
2. Features
PCA9685_1
Product data sheet
The active LOW Output Enable input pin (OE) allows asynchronous control of the LED
outputs and can be used to set all the outputs to a defined I
state. The OE can also be used to externally ‘pulse width modulate’ the outputs, which is
useful when multiple devices need to be dimmed or blinked together using software
control.
Software programmable LED All Call and three Sub Call I
defined groups of PCA9685 devices to respond to a common I
for example, all red LEDs to be turned on or off at the same time or marquee chasing
effect, thus minimizing I
62 devices on the same bus.
The Software Reset (SWRST) General Call allows the master to perform a reset of the
PCA9685 through the I
registers to their default state causing the outputs to be set LOW. This allows an easy and
quick way to reconfigure all device registers to the same condition via software.
I
I
I
I
I
I
I
I
I
I
I
16 LED drivers. Each output programmable at:
1 MHz Fast-mode Plus compatible I
on SDA output for driving high capacitive buses
4096-step (12-bit) linear programmable brightness per LED output varying from fully
off (default) to maximum brightness
LED output frequency (all LEDs) typically varies from 40 Hz to 1000 Hz (Default of 1Eh
in PRE_SCALE register results in a 200 Hz refresh rate with oscillator clock of
25 MHz.)
Sixteen totem pole outputs (sink 25 mA and source 10 mA at 5 V) with software
programmable open-drain LED outputs selection (default at totem pole). No input
function.
Output state change programmable on the Acknowledge or the STOP Command to
update outputs byte-by-byte or all at the same time (default to ‘Change on STOP’).
Active LOW Output Enable (OE) input pin. LEDn outputs programmable to logic 1,
logic 0 (default at power-up) or ‘high-impedance’ when OE is HIGH.
6 hardware address pins allow 62 PCA9685 devices to be connected to the same
I
Toggling OE allows for hardware LED blinking
4 software programmable I
Sub Call addresses) allow groups of devices to be addressed at the same time in any
combination (for example, one register used for ‘All Call’ so that all the PCA9685s on
the I
different addresses so that
time in a group). Software enable and disable for these I
Software Reset feature (SWRST General Call) allows the device to be reset through
the I
2
N
N
N
N
C-bus
Off
On
Programmable LED brightness
Programmable LED turn-on time to help reduce EMI
2
2
C-bus can be addressed at the same time and the second register used for three
C-bus
2
2
Rev. 01 — 24 July 2008
C-bus, identical to the Power-On Reset (POR) that initializes the
C-bus commands. Six hardware address pins allow up to
2
1
C-bus addresses (one LED All Call address and three LED
3
of all devices on the bus can be addressed at the same
16-channel, 12-bit PWM Fm+ I
2
C-bus interface with 30 mA high drive capability
2
C-bus addresses allow all or
2
2
C-bus programmable logic
C-bus address.
2
C-bus address, allowing
2
C-bus LED controller
PCA9685
© NXP B.V. 2008. All rights reserved.
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