Sn51dp Datasheet [upd] -

Delivered in a compact, surface-mount MSOP-10 or SSOP-10 footprint. Its dimensions span roughly 3.9mm in length, 7.9mm in width, and 1.7mm in height.

[12V Rail] ---> [Inductor] --------+--------[Diode]----> [LED Backlight +] | | [External MOSFET] | | | [GATE Pin 2] ------+ | v [OVP Pin 3] <--- [Resistor Divider]+

According to data listed on component sourcing profiles like UTSource Electronic Solutions , the SN51DP operates within tightly controlled electrical constraints. Minimum 3.5V to a maximum of 7V.

: Current Sense Input. Connects to a low-resistance current-sensing resistor at the source of the switching MOSFET to monitor peak inductor current. sn51dp datasheet

Test for a stable 12V input at Pin 1. If this voltage is missing, the fault is likely in the preceding power supply stage rather than the driver IC itself.

LED Current Setting. Connects to an external resistor to establish the master operational current flowing through the LED backlight strips.

Over-Voltage Protection. Samples the boosted output voltage via a resistive divider network. If the feedback path opens or voltage spikes above a safe limit, the IC shifts into a latch-off protective mode. Practical Board Applications and TV Models Delivered in a compact, surface-mount MSOP-10 or SSOP-10

| Parameter | Symbol | Min | Typical | Max | Unit | Description | | :--- | :--- | :--- | :--- | :--- | :--- | :--- | | Operating Supply Voltage | VDD | 1.6 | 3.3 | 5.5 | V | Logic supply for the IC's internal circuitry. | | Power Input Voltage | VIN | 4.5 | 12 | 28 | V | Input supply for the boost converter stage. | | Output Voltage | VOUT | 0.8 | - | 72 | V | Adjustable boosted output for LED strings (Max dependent on design). | | Max Load Current | ILoad | - | - | 20 | mA | Current per control channel (control side). | | Quiescent Current | IQ | - | 1.5 | - | μA | Current consumed by IC with no load (Standby). | | Operating Temp | Toper | -40 | - | 85 | °C | Functional temperature range of the device. | | Storage Temp | Tstg | -65 | - | 150 | °C | Non-operating storage temperature range. |

– Dimming signal entry point. Accepts Pulse Width Modulation (PWM) or analog control inputs to govern backlight intensity. Operational Principles

"When the OVP pin voltage drifts above 2V due to resistor aging, the IC enters protection mode. Adding a 10kΩ resistor from Pin 9 to ground can temporarily lower the voltage, but the proper fix is replacing the faulty divider resistors." Minimum 3

In some configurations, the OB3350CP is used as a direct replacement, though it may be in a 8-pin package rather than 10-pin, requiring layout adjustments.

Always ensure you are buying from a reputable source. Counterfeit or salvaged chips may fail prematurely.