ZHCSLM9B August 2020 – May 2024 LP8866S-Q1
PRODUCTION DATA
The Six LED driver channels of the LP8866S-Q1 device is configured by the LED_SET resistor, which supports applications using one to Six LED strings. Resistor with 1% accuracy is needed to ensure proper operation. The driver channels can also be tied together in groups of one, two or three. This allows the LP8866S-Q1 device to drive three 300mA LED strings, two 450mA LED strings, or one 900mA LED string. The LED strings are always appropriately phase shifted for their string configuration. This reduces the ripple seen at the boost output, which allows smaller output capacitors and reduces audible ringing in the capacitors. Phase shift increases the load frequency, which can move potential capacitor noise above the audible band while still keeping PWM frequency low to support a higher dimming ratio.
When the LP8866S-Q1 device is firstly powered on, the string configuration is configured by the LED_SET resistor and the phases of each channel are automatically configured. The LED string configuration must not be changed unless the LP8866S-Q1 is powered off in shutdown state. The unused LEDx pins should be tied to ground.
| R_LED_SET (kΩ) | CONFIGURATION | OUT1 | OUT2 | OUT3 | OUT4 | OUT5 | OUT6 | AUTOMATIC PHASE SHIFT |
|---|---|---|---|---|---|---|---|---|
| 3.92 | 6 Channels | 150mA | 150mA | 150mA | 150mA | 150mA | 150mA | 60° |
| 4.75 | 5 Channels | 150mA | 150mA | 150mA | 150mA | 150mA | (Tied to GND) | 72° |
| 5.76 | 4 Channels | 150mA | 150mA | 150mA | 150mA | (Tied to GND) | (Tied to GND) | 90° |
| 7.87 | 3 Channels | 150mA | 150mA | 150mA | (Tied to GND) | (Tied to GND) | (Tied to GND) | 120° |
| 11 | 2 Channels | 150mA | 150mA | (Tied to GND) | (Tied to GND) | (Tied to GND) | (Tied to GND) | 180° |
| 17.8 | 3 Channels | 300mA | 300mA | 300mA | 120° | |||
| 42.2 | 2 Channels | 450mA | 450mA | 180° | ||||
| 124 | 1 Channels | 900mA | None | |||||