CS1615-FSZ

CS1615 CS1616 Single Stage Dimmable Offline AC/DC Controller for LED Lamps Features Overview • Best-in-class Dimmer Compatibility - Leading-edge (TRIAC) Dimmers - Trailing-edge Dimmers - Digital Dimmers (Dimmers with an Integrated Power Supply) • Flicker-free Dimming • 0% to 100% Smooth Dimming • Primary-side Regulation (PSR) • Active Power Factor Correction (PFC) - >0.9 Power Factor • Constant-current Output - Flyback - Buck-boost • Tight LED Current Regulation: Better than ±5% • Low THD: Less Than 20% • Up to 90% Efficiency • Fast Startup • IEC61000-3-2 Compliant • Meets NEMA SSL 6 Dimming Standard - Closely Matches Incandescent S-curve • Protection Features - Output Open Circuit - Output Short Circuit - External Overtemperature Using NTC The CS1615 and CS1616 are high-performance single stage dimmable offline AC/DC controllers. The CS1615/16 is a cost-effective solution that provides unmatched singleand multi-lamp dimmer-compatibility performance for dimmable LED applications. The CS1615 is designed for 120VAC line voltage applications, and the CS1616 is designed for 230VAC line voltage applications. L1 Across a broad range of dimmers, the CS1615/16 provides smooth flicker free dimming, and consistently dims to nearly zero light output, which closely matches the dimming performance of incandescent light bulbs. Cirrus Logic’s patent pending approach to dimmer compatibility provides full functionality on a wide range of dimmers, including leading-edge, trailing-edge, and digital dimmers. Applications • • • • Retro-fit LED Lamps External LED Drivers LED Luminaries Commercial Lighting Ordering Information See page 14. Vrec t C5 T1 C6 R4 D4 LED+ R6 R5 C7 LEDR2 BR1 D3 R3 BR1 VA UX C2 FBSENSE D1 BR1 Q2 14 VDD SGND C4 R7 11 FBAUX 16 BR1 C3 Q3 GD 13 5 SOURCE R1 C1 VAUX IAC CS1615/16 AC Mains D5 2 D2 Q1 Z1 4 eOTP CTRL1 CTRL2 8 9 C8 10 GND 12 RS R S ense R8 NTC R CTRL1 RCTRL2 Preliminary Product Information Cirrus Logic, Inc. http://www.cirrus.com This document contains information for a product under development. Cirrus Logic reserves the right to modify this product without notice. Copyright  Cirrus Logic, Inc. 2013 (All Rights Reserved) APR’13 DS961PP5 CS1615/16 1. INTRODUCTION VDD VDD Voltage Regulator 14 VDD(on) VDD(off ) VZ I ref 15k 2 OLP - + VS OURCE(th) Peak Control + - + - - t VAUX CTRL1 eOTP CTRL2 11 FBSENSE 16 FBAUX 3 CLAMP VOCP (th) VP k_Max (th ) DAC SGND GND VOLP (th ) + ADC - 5 12 3 OCP SOURCE GD - Blank IAC 13 POR + + V FS TA RT(th ) 4 Output Overvoltage 8 Zero-current Detect ICONNE CT 10 9 + - VOV P(th ) VDD MUX + - VZCD(th) VDD V CONNE CT(th) - I CLA MP + Figure 1. CS1615/16 Block Diagram A typical schematic using the CS1615/16 IC is shown on the previous page. Startup current is provided from a patent-pending, external, highvoltage source-follower network. In addition to providing startup current, this unique topology is integral in providing compatibility with digital dimmers by ensuring VDD power is always available to the IC. During normal operation, an auxiliary winding on the flyback transformer or buck-boost inductor back-biases the source-follower circuit and provides steady-state operating current to the IC to improve system efficiency. Rectified input voltage Vrect is sensed as a current into pin IAC and is used to control the adaptive dimmer-compatibility algorithm and to extract the phase of the input voltage for output dimming control. The SOURCE pin is used to provide a control signal for the high-voltage source-follower circuit during Leadingedge Mode and Trailing-edge Mode; it also provides the current during startup. 2 The digital dual-mode controller is implemented with peakcurrent mode primary-side regulation, which eliminates the need for additional components to provide feedback from the secondary and reduces system cost and complexity. Voltage across a user-selected resistor is sensed through pin FBSENSE to control the peak current of the primary-side inductor. Leadingedge and trailing-edge blanking on pin FBSENSE prevents false triggering. The required target LED current and average flyback transformer and buck-boost inductor input current are set by attaching resistors RCTRL1 and RCTRL2 on pins CTRL1 and CTRL2, respectively. The controller ensures half line-cycle averaged constant output current. Pin FBAUX is used for zero-current detection to ensure quasi-resonant switching of the single stage output. When an external negative temperature coefficient (NTC) thermistor is connected to pin eOTP, the CS1615/16 monitors the system temperature, allowing the controller to reduce the output current of the system. If the temperature reaches a designated high set point, the IC is shut down and stops switching. DS961PP5 CS1615/16 2. PIN DESCRIPTION NC 1 16 FBAUX Zero-current Detect Rectifier Voltage Sense IAC 2 15 NC No Connect Voltage Clamp Current Source CLAMP 3 14 VDD IC Supply Voltage Source Ground SGND 4 13 GD Gate Drive Source Switch SOURCE 5 12 GND Ground No Connect NC 6 11 FBSENSE Flyback Current Sense No Connect NC 7 10 eOTP External Overtemperature Protection Dimmer Hold Current CTRL1 8 9 CTRL2 LED Load Current No Connect 16-lead SOIC and TSSOP Figure 2. CS1615/16 Pin Assignments Pin Name Pin # I/O NC 1 IN No Connect — Leave pin unconnected. IAC 2 IN Rectifier Voltage Sense — A current proportional to the rectified line voltage is fed into this pin. The current is measured with an A/D converter. CLAMP 3 OUT Voltage Clamp Current Source — Connect to a voltage clamp circuit on the sourceswitched dimmer-compatibility circuit. SGND 4 PWR Source Ground — Common reference current return for the SOURCE pin. SOURCE 5 IN Description Source Switch — Connected to the source of the source-switched external high-voltage FET. NC 6 IN No Connect — Connect this pin to VDD using a 47k pull-up resistor. NC 7 IN No Connect — Connect this pin to VDD using a 47kpull-up resistor. CTRL1 8 IN Dimmer Hold Current — Connect a resistor to this pin to set the minimum input current being pulled by the flyback/buck-boost stage. CTRL2 9 IN LED Load Current — Connect a resistor to this pin to set the LED current. eOTP 10 IN External Overtemperature Protection — Connect an external NTC thermistor to this pin, allowing the internal A/D converter to sample the change to NTC resistance. FBSENSE 11 IN Feedback Current Sense — The current flowing in the power FET is sensed across a resistor. The resulting voltage is applied to this pin and digitized for use by the computational logic to determine the FET's duty cycle. GND 12 PWR Ground — Common reference. Current return for both the input signal portion of the IC and the gate driver. GD 13 OUT Gate Drive — Gate drive for the power FET. VDD 14 PWR IC Supply Voltage — Connect a storage capacitor to this pin to serve as a reservoir for operating current for the device, including the gate drive current to the power transistor. NC 15 - FBAUX 16 IN DS961PP5 No Connect — Leave pin unconnected. Zero-current Detect — Connect to the flyback/buck-boost inductor auxiliary winding for demagnetization current zero-crossing detection. 3 CS1615/16 3. CHARACTERISTICS AND SPECIFICATIONS 3.1 Electrical Characteristics Typical characteristics conditions: • TA = 25 °C, VDD = 12V, GND = 0 V • All voltages are measured with respect to GND. • Unless otherwise specified, all currents are positive when flowing into the IC. Parameter Minimum/Maximum characteristics conditions: • TJ = -40°C to +125 °C, VDD = 11V to 17V, GND = 0 V Condition Symbol Min Typ Max Unit After Turn-on VDD 11 - 17 V Turn-on Threshold Voltage VDD Increasing VST(th) - 8.5 - V Turn-off Threshold Voltage (UVLO) VDD Decreasing VSTP(th) - 7.5 - V IDD = 20mA VZ 18.5 - 19.8 V VDD