9.1.2.1 Setting Boost Switching and PWM Dimming Frequencies
Boost switching and PWM dimming frequencies can be set via resistor when BOOST_FSET_EN = 1 and PWM_FSET_EN = 1. Available options are shown in Table 14.
Table 14. Configuring PWM Dimming Frequency With an External Resistor
RFSET [kΩ]
(TOLERANCE) |
ƒSW [kHz]
BOOST_FSET_EN = 1 |
ƒPWM [Hz] (RESOLUTION)
PWM_FSET_EN = 1 |
| Floating or FSET pin pulled HIGH |
1250 |
9616 (10-bit) |
| 470 k - 1 M (±5%) |
312 |
2402 (12-bit) |
| 300 k, 330 k (±5%) |
312 |
4808 (11-bit) |
| 200 k (±5%) |
312 |
6010 (10-bit) |
| 147 k, 150k, 154 k, 158k (±1%) |
312 |
9616 (10-bit) |
| 121 k (±1%) |
312 |
12020 (9-bit) |
| 100 k (±1%) |
312 |
14424 (9-bit) |
| 86.6 k (±1%) |
312 |
16828 (9-bit) |
| 75 k (±1%) |
312 |
19232 (9-bit) |
| 63.4 k (±1%) |
625 |
2402 (12-bit) |
| 52.3 k, 53.6 k (±1%) |
625 |
4808 (11-bit) |
| 44.2k, 45.3 k (±1%) |
625 |
6010 (10-bit) |
| 39.2 k (±1%) |
625 |
9616 (10-bit) |
| 34 k (±1%) |
625 |
12020 (9-bit) |
| 30.1k (±1%) |
625 |
14424 (9-bit) |
| 26.1 k (±1%) |
625 |
16828 (9-bit) |
| 23.2 k (±1%) |
625 |
19232 (9-bit) |
| 20.5 k (±1%) |
1250 |
2402 (12-bit) |
| 18.7 k (±1%) |
1250 |
4808 (11-bit) |
| 16.5k (±1%) |
1250 |
6010 (10-bit) |
| 14.7 k (±1%) |
1250 |
9616 (10-bit) |
| 13 k (±1%) |
1250 |
12020 (9-bit) |
| 11.8k (±1%) |
1250 |
14424 (9-bit) |
| 10.7 k (±1%) |
1250 |
16828 (9-bit) |
| 9.76 k (±1%) |
1250 |
19232 (9-bit) |
| FSET pin shorted to GND |
1250 |
Same as PWM input frequency |