The LP8867-Q1, LP8869-Q1 is an automotive highly-integrated, low-EMI, easy-to-use LED driver with DC-DC converter. The DC-DC converter supports both boost and SEPIC mode operation. The device has four or three high-precision current sinks that can be combined for higher current capability.
The DC-DC converter has adaptive output voltage control based on the LED forward voltages. This feature minimizes the power consumption by adjusting the voltage to the lowest sufficient level in all conditions. For EMI reduction DC-DC supports spread spectrum for switching frequency and an external synchronization with dedicated pin. A wide-range adjustable frequency allows the LP886x-Q1 to avoid disturbance for sensitive frequency band.
The input voltage range for the LP886x-Q1 is from 4.5 V to 40 V to support automotive start-stop and load dump condition. The LP886x-Q1 integrates extensive fault detection features.
PART NUMBER | PACKAGE | BODY SIZE (NOM) |
---|---|---|
LP8867-Q1 | HTSSOP (20) | 6.50 mm × 4.40 mm |
LP8869-Q1 |
LP8869-Q1 | LP8869C-Q1 | LP8867-Q1 | LP8867C-Q1 | |
Number of LED channels | 3 | 3 | 4 | 4 |
LED current / channel | 120 mA | 120 mA | 120 mA | 120 mA |
Power Line FET Control and Automatic Current De-rating Support | Yes | No | Yes | No |
PIN | TYPE(1) | DESCRIPTION | |
---|---|---|---|
NO. | NAME | ||
1 | VIN | A | Input power pin; input voltage OVP detection pin; input current sense positive input pin. |
2 | LDO | A | Output of internal LDO; connect a 1-μF decoupling capacitor between this pin and noise-free ground. Put the capacitor as close to the chip as possible. |
3 | FSET | A | DC-DC (boost or SEPIC) switching frequency setting resistor; for normal operation, resistor value from 24 kΩ to 219 kΩ must be connected between this pin and ground. |
4 | VDDIO/EN | I | Enable input for the device as well as supply input (VDDIO) for digital pins. |
5 | FAULT | OD | Fault signal output. If unused, the pin may be left floating. |
6 | SYNC | I | Input for synchronizing DC-DC converter. If synchronization is not used, connect this pin to ground to disable spread spectrum or to VDDIO/EN to enable spread spectrum. |
7 | PWM | I | PWM dimming input. |
8 | TSENSE | A | Input for NTC resistor divider. Refer to LED Current Dimming With External Temperature Sensor for proper connection. If unused, the pin must be left floating. |
9 | TSET | A | Input for NTC resistor divider. Refer to LED Current Dimming With External Temperature Sensor for proper connection. If unused, the pin must be connected to GND. |
10 | ISET | A | LED current setting resistor; for normal operation, resistor value from 20 kΩ to 129 kΩ must be connected between this pin and ground. |
11 | GND | G | Ground. |
12 | OUT4/GND | A | Current sink output for LP8867-Q1
This pin must be connected to ground if not used. GND pin for LP8869-Q1 |
13 | OUT3 | A | Current sink output.
This pin must be connected to ground if not used. |
14 | OUT2 | A | Current sink output.
This pin must be connected to ground if not used. |
15 | OUT1 | A | Current sink output.
This pin must be connected to ground if not used. |
16 | FB | A | DC-DC (boost or SEPIC) feedback input; for normal operation this pin must be connected to the middle of a resistor divider between VOUT and ground using feedback resistor values greater than 5kΩ. |
17 | PGND | G | DC-DC (boost or SEPIC) power ground. |
18 | SW | A | DC-DC (boost or SEPIC) switch pin. |
19 | SD | A | Power-line FET control. Open Drain (current sink type) Output. If unused, the pin may be left floating. |
20 | VSENSE_N | A | Input current sense negative input. Connect to VIN pin when input current sense resistor is not used. |