ZHCSQX1A August 2022 – December 2022 LP5891-Q1
PRODUCTION DATA
The LP5891-Q1 device is able to adjust the output current of all constant-current outputs simultaneously. This function is called global brightness control (BC). The global BC for all outputs is programmed with a 3-bit register, thus all output currents can be adjusted in eight steps for a given current-programming resistor, RIREF. When the 3-bit BC register changes, the gain of output current, GAINBC changes as Table 8-2 below.
BC Register (BC) | Current Gain (GAINBC) |
---|---|
000b | 24.17 |
001b | 30.57 |
010b | 49.49 |
011b (default) | 86.61 |
100b | 103.94 |
101b | 129.92 |
110b | 148.48 |
111b | 173.23 |
The maximum output current per channel, IOUTSET, is determined by resistor RIREF, and the GAINBC. The voltage on IREF is typically 0.8 V. RIREF can be calculated by Equation 1 below. For noise immunity purpose, suggest RIREF < 40 kΩ.