CP1N |
2 |
O |
Charge pump first-stage flying capacitor negative output, charge pump to provide gate-drive voltage for external MOSFET. Connect a 10-nF flying capacitor between CP1P and CP1N. |
CP1P |
1 |
O |
Charge pump first-stage flying capacitor positive output |
CP2N |
4 |
O |
Charge pump second-stage flying capacitor negative output. Connect a 10-nF flying capacitor between CP2P and CP2N. |
CP2P |
5 |
O |
Charge pump second-stage flying capacitor positive output |
CPOUT |
6 |
O |
Charge-pump output voltage. Connect a 150-nF storage capacitor between CPOUT and IN. |
DERATE |
9 |
I |
Voltage input for current derating. Connect to GND to disable the derate feature. |
DIAGEN |
8 |
I |
Input pin with comparator to enable diagnostics to avoid false open-fault diagnostics when the device works in low-dropout mode. Use a resistor divider to set a threshold according to the LED forward voltage. |
FAULT |
17 |
I/O |
Fault bus pin to support one-fails–all-fail feature. Float: one-fails–all-fail; strong pullup: only-fails-off |
FD |
13 |
I |
Full duty-cycle input, HIGH: 100% PWM; LOW: using external resistor-capacitor network to set PWM duty cycle |
G1 |
26 |
O |
Channel 1 gate driver output, connect to CH 1 N-channel MOSFET gate |
G2 |
23 |
O |
Channel 2 gate driver output, connect to CH 2 N-channel MOSFET gate |
G3 |
20 |
O |
Channel 3 gate driver output, connect to CH 3 N-channel MOSFET gate |
GND |
3 |
— |
GND |
ICTRL |
14 |
I |
Analog dimming input, modulates the regulation voltage across the current-sense resistor. Apply a voltage source or connect a resistor between ICTRL and GND to set the analog dimming ratio. |
IN |
7 |
I |
Power supply for the device. LED current only flows from the external MOSFET to the LED. |
ISN1 |
27 |
I |
Channel 1 current-sense negative input. Connect a current-sense resistor between ISP and ISN1 to set the CH 1 current. |
ISN2 |
24 |
I |
Channel 2 current-sense negative input. Connect a current-sense resistor between ISP and ISN2 to set the CH 2 current. |
ISN3 |
21 |
I |
Channel 3 current-sense negative input. Connect a current-sense resistor between ISP and ISN3 to set the CH 3 current. |
IREF |
15 |
O |
Internal current reference. Connect an 8-kΩ resistor between IREF and GND, |
ISP |
28 |
I |
Channel current-sense positive input. Kelvin-sense to LED sense-resistor positive node. |
PWM1 |
10 |
I |
Channel 1 PWM input |
PWM2 |
11 |
I |
Channel 2 PWM input |
PWM3 |
12 |
I |
Channel 3 PWM input |
PWMCHG |
16 |
I/O |
On-chip PWM generator pin for external R-C. Connect a resistor and a capacitor between PWMCHG and GND to set the PWM duty cycle and frequency. |
PWMOUT |
18 |
O |
High-voltage PWM open-drain output. Connect a 10-kΩ resistor between IN and PWMOUT |
SENSE1 |
25 |
I/O |
Channel 1 diagnostics pin. Connect to the CH 1 MOSFET source terminal |
SENSE2 |
22 |
I/O |
Channel 2 diagnostics pin. Connect to the CH 2 MOSFET source terminal |
SENSE3 |
19 |
I/O |
Channel 3 diagnostics pin. Connect to the CH 3 MOSFET source terminal |