The 34845 series represents a high efficiency, LED driver for use in backlighting LCD displays from 10” to 17”+. Operating from supplies of 5.0 V to 21 V, the 34845 series is capable of driving up to 16 LEDs in series in each of 6 strings. The LED current tolerance in the 6 strings is within ±2% and is set using a resistor to GND.
PWM dimming is performed by applying a PWM input signal to the PWM pin which modulates the LED channels directly.
The integrated boost converter uses dynamic headroom control to automatically set the output voltage. There are three device versions for boost frequency, the 34845 is 600 kHz, the 34845A is 1.2 MHz and the 34845B is 300kHz. External compensation allows the use of different inductor/ capacitor combinations.
The 34845 includes fault protection modes for LED short and open, over temperature, over current and over voltage errors. The OVP level can be set by using an external resistor divider.
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Features
- Input voltage of 5.0 to 21 V
- Boost output voltage up to 60 V
- 2.0 A integrated boost FET
- Fixed boost frequency to 300kHz, 600 kHz or 1.2 MHz
- OTP, OCP, UVLO fault detection, LED short/open protection
- Programmable LED current between 3.0 mA and 30 mA
- 24-Ld 4x4x0.65 mm WQFN Package
Featured Documentation
Current Updates & Releases
- KIT34845EPEVME: Evaluation Kit - 34845, Low Cost 6 Channel LED Backlight Driver with Integrated Power Supply
- KITLEDBKLT16EVBE: Evaluation KIT-16 Ch LED driver board (256 LEDs)
Product Specifications
| Regulator - Output Voltage | 60, 60 |
| Regulator - Output Current (A) | 2.1, 2.35 |
| Supply Voltage - Min (V) | 5 |
| Supply Voltage - Max (V) | 21 |
| Interface and Input Control | Parallel |
| Ambient Operating Temperature (Ta) - Min (°C) | -40 |
| Ambient Operating Temperature (Ta) - Max (°C) | 85 |
