NCP1370 Product Preview Dimmable Quasi-Resonant Primary Side Current-Mode Controller for LED TV www.onsemi.com Backlight The NCP1370 is a PWM current mode controller targeting isolated flyback and nonisolated constant current topologies. The controller QUASIRESONANT PWM operates in a quasiresonant mode to provide high efficiency. Thanks CONTROLLER FOR to a novel control method, the device is able to precisely regulate a LED DRIVERS constant LED current from the primary side. This removes the need for secondary side feedback circuitry, biasing and an optocoupler. The device is highly integrated with a minimum number of external MARKING components. A robust suite of safety protection is built in to simplify DIAGRAM the design. This device supports analog/digital dimming and both 8 modes can be combined to enhance dimming precision. The NCP1370 SOIC8 NCP1370x 8 has a programmable peak current limit to optimize design D SUFFIX ALYW compatibility over a wide range of applications. The controller 1 CASE 751 features a standby mode with reduced current consumption. 1 Features NCP1370 = Specific Device Code Quasiresonant Peak Currentmode Control Operation x = Device Option (A or B) A = Assembly Location Primary Side Sensing (no optocoupler needed) L = Wafer Lot Wide V Range CC Y = Year Source 300 mA / Sink 500 mA Totem Pole Driver with 12 V Gate W = Work Week = PbFree Package Clamp Precise LED Constant Current Regulation 1% Typical Line Feedforward for Enhanced Regulation Accuracy PIN CONNECTIONS Low LED Current Ripple 1 ILIM DIM 500 mV 1.2% Guaranteed Voltage Reference for Current ZCD VIN Regulation CS VCC Programmable CyclebyCycle Peak Current Limit GND DRV Low V Allowing to use a Standby Power Supply to Power the CC(on) (Top View) Device Analog or Digital Dimming ORDERING INFORMATION Wide Temperature Range of 40 to + 125C See detailed ordering and shipping information in the package Robust Protection Features dimensions section on page 18 of this data sheet. LED Open Circuit Protection V Over Voltage Protection CC Secondary Diode Short Protection Output Short Circuit Protection Shorted Current Sense Pin Fault Detection Brownout Typical Applications V Under Voltage Lockout TV Backlight CC Thermal Shutdown Lighting with Auxiliary Power Supply Pbfree, Halidefree MSL1 Product This document contains information on a product under development. ON Semiconductor reserves the right to change or discontinue this product without notice. Semiconductor Components Industries, LLC, 2016 1 Publication Order Number: February, 2016 Rev. P1 NCP1370/DNCP1370 . Aux V DIM 1 8 2 7 V BIAS 3 6 45 Figure 1. Typical Application Schematic for NCP1370 Table 1. PRODUCTS TABLE Block or Electrical Parameter NCP1370B NCP1370A Brownout blanking time t 2 ms 100 s BO(blank) Blanking circuit for leakage inductance reset detection ON ON V OVP Autorecovery Latched CC Switching cycles count before activating the output diode short circuit 4 cycles 4 cycles protection: V > V CS CS(stop) Output Diode Short Circuit protection Autorecovery Latched Adjustable OVP Autorecovery timer 1 second 4 seconds CS short circuit protection (impedance measurement before startup) ON OFF rd nd High mains valley switching 3 2 (all HL valleys incremented by 1) Propagation delay from ZCD to DRV high state t ON ON ZCD(DEM) Table 2. PIN FUNCTION DESCRIPTION Pin N Pin Name Function Pin Description nd 1 ILIM Peak current limit and 2 This pin sets the cyclebycycle peak current limit threshold and the threshold for over current protection secondary diode short detection 2 ZCD Zero Crossing Detection Connected to the auxiliary winding, this pin detects the core reset event. 3 CS Current sense This pin monitors the primary peak current. 4 GND The controller ground 5 DRV Driver output The drivers output to an external MOSFET 6 VCC Supplies the controller This pin is connected to an external power supply. 7 VIN BrownOut This pin observes the HV rail and protects the circuit in case of low main conditions. Input voltage sensing This pin also sense the line voltage for the valley selection and the line feedforward Over Voltage Protection A Zener diode can also be used to pullup the pin and stop the controller for adjustable OVP protection 8 DIM Analog / PWM dimming This pin is used for analog or PWM dimming control. An analog signal than can be varied between V and V can be used to vary the current, or a DIM(EN) DIM100 PWM signal with an amplitude greater than V . DIM100 This pin is also used for the OFF mode www.onsemi.com 2