FP7175LR-G1

FP7175 LED Driver with Average-Mode Constant Current Control General Description The FP7175 is an average current mode control LED driver IC operating in a constant off-time mode. FP7175 does not produce a peak-to-average error, and therefore greatly improves accuracy, line and load regulation of the LED current without any need for loop compensation or high-side current sensing. The output LED current accuracy is ±2%. The FP7175 can be powered from an 8.0 - 100V supply. PWM & Linear dimming input is provided that accepts an external control TTL compatible signal. The output current can be programmed by an internal 250mV reference. Features  Fast Average Current Control  Internal 8 to 100V Linear Regulator  Linear and PWM Dimming Capability  Output Short Circuit Protection with Skip Mode  Requires Few External Components for Operation Applications  DC/DC or AC/DC LED Driver Applications  LED Street Lighting  Back Lighting of Flat Panel Displays  General Purpose Constant Current Source  Signage and Decorative LED Lighting  Chargers Typical Application Circuit VIN LED+ GATE VDD FP7175 GND GND DIM CS VIN LEDLinear & PWM Dimming This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 1/14 FP7175 Function Block Diagram VIN Regulator Internal supply UVLO VDD Average Current Logic Control GATE POR DIM 200mV/250mV DIM to CS ratio=0.167 LEB GND SCP 550mV TOFF Timer OTP CS Pin Descriptions SOT23-6L Top View 1 GND 2 CS 3 CBXXX GATE Name 6 VDD No. I / O GATE 1 O GND 2 P 5 DIM CS 3 I 4 VIN VIN 4 P DIM 5 I VDD 6 I Description This pin is the output GATE driver for an external N-channel power MOSFET. Ground return for all internal circuitry. This pin is the current sense pin used to sense the FET current by means of an external sense resistor. This pin is the input of an 8 - 100V linear regulator. This pin is the linear & PWM dimming input of the IC. This is the power supply pin for all internal circuits. This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 2/14 FP7175 Marking Information SOT23-6L CBXXX Lot Number Year Part Number Code Lot Number: Wafer lot number’s last two digits For Example: XX486 86 Year: Production year’s last digit Part Number Code: Part number identification code for this product. It should be always “CB”. This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 3/14 FP7175 Ordering Information Part Number FP7175LR-G1 Code Operating Temperature Package MOQ Description CB -25°C ~ +85°C SOT23-6L 3000 EA Tape & Reel Absolute Maximum Ratings Parameter Symbol Power Supply Voltage Conditions Max. Unit VIN to GND 100 V VDD VDD to GND 8.5 V VDD-0.3V V 455 mW 220 °C / W -25 +85 °C -40 +150 °C +260 °C -0.3 Allowable Power Dissipation PD Junction to Ambient Thermal Resistance θJA SOT23-6L TA≦+25°C Operating Temperature SOT23-6L Lead Temperature Typ. VIN CS, DIM, GATE Storage Temperature Min. TS SOT23-6L (soldering, 10 sec) IR Re-flow Soldering Curve This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 4/14 FP7175 Recommended Operating Conditions Parameter Symbol Supply Voltage Conditions VIN Operating Temperature Min. Typ. Max. Unit 8 100 V -25 85 °C DC Electrical Characteristics (VIN=11V,TA = 25°C, unless otherwise noted) Parameter Symbol Conditions Min. Typ. Max. Unit 7.25 7.5 7.75 V 0 - 1.0 V 100 mV Internal Regulator Internally regulated voltage VDD Line regulation of VDD ΔVDD,line Load regulation of VDD ΔVDD,load VDD undervoltage lockout threshold VDD undervoltage lockout hysteresis VIN = 8V, IDD(ext)= 0, 500pF at GATE;DIM = VDD VIN = 8 – 100V, IDD(ext)=0, 500pF at GATE; DIM = VDD IDD(ext) = 0 – 0.6mA, 500pF at GATE; DIM = VDD 0 UVLO VDD rising 6.5 V ΔUVLO VDD falling 500 mV PWM Dimming Pin DIM input low voltage VEN(lo) VIN = 8 - 100V Pin DIM input high voltage VEN(hi) VIN = 8 - 100V 0.1 V 1.6 V Average Current Sense Logic Current sense reference voltage VCS DIM-to-CS voltage ratio 245 AV(DIM) AVDIM DIM-to-CS voltage offset (OFFSET) 250 DIM input voltage, enable mV 10 mV 5 mV 0.167 Offset = VCS – AV(DIM)‧VDIM VDIM=1.2V 0 CS threshold temp regulation DIM input voltage, shutdown 255 VDIM(OFF) 200 mV △ VDIM(OFF) 250 mV Current sense blanking interval TBLANK Minimum steady-state duty cycle TON(min) 150 CS=VCS + 30mV 320 ns 1000 ns 605 mV 150 ns 650 us 600 ns Short Circuit Protection Hiccup threshold voltage VCS 495 550 Current limit delay CS - GATE TDELAY CS=VCS + 30mV Short circuit hiccup time THICCUP Minimum on-time (short circuit) TON(min) CS=VDD ISOURCE VGATE = 0V, VDD = 7.5V 165 mA GATE sinking current ISINK VGATE = VDD, VDD = 7.5V 165 mA GATE output rise time tRISE CGATE = 500pF, VDD = 7.5V 30 50 ns GATE output fall time tFALL CGATE = 500pF, VDD = 7.5V 30 50 ns 450 550 GATE Driver GATE sourcing current This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 5/14 FP7175 Parameter Symbol Conditions Min. Typ. Max. Unit OFF-Time Minimum off time TOFF(MIM) 0.6 us Maximum off time TOFF(MAX) 50 us Maximum on time TON(MAX) 60 us This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 6/14 FP7175 Function Description Input Voltage Regulator The FP7175 can be powered directly from its VIN pin and can work from 8.5 - 100VDC at its VIN pin. When a voltage is applied at the VIN pin, the FP7175 maintains a constant 7.5V at the VDD pin. This voltage is used to power the IC and any external resistor dividers needed to control the IC. The VDD pin must be bypassed by a low ESR capacitor to provide a low impedance path for the high frequency current of the output GATE driver. The FP7175 can also be operated by supplying a voltage at the VDD pin greater than the internally regulated voltage. This will turn off the internal linear regulator of the IC and the FP7175 will operate directly off the voltage supplied at the VDD pin. Please note that this external voltage at the VDD pin should not exceed 8.5V. In the above equation, fS is the switching frequency and QG is the GATE charge of the external FET (which can be obtained from the datasheet of the FET). This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 7/14 FP7175 Average Current Control The LED current is detected using a sense resistor at the CS pin. The feedback operates in a fast open-loop mode. No compensation is required. When the voltage at the DIM input VDIM ≥ 1.5V, output current is programmed simply as: ILED ( A )= 0.25 V RCS (Ω) Otherwise: ILED ( A )= CS VDIM ( V ) × 0.167 R CS (Ω) LED Current Average Current = 0.25V RCS 0.25V t t The above equations are only valid for continuous conduction of the output inductor. It is a good practice to design the inductor such that the switching ripple current in it is 25% of its average peak-to-peak, full load, DC current. GATE Output The GATE output of the FP7175 is used to drive an external MOSFET. It is recommended that the gate charge QG of the external MOSFET be less than 25nC for switching frequencies ≤100kHz and less than 15nC for switching frequencies >100kHz. This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 8/14 FP7175 Output Short Circuit Protection The short circuit protection comparator trips when the voltage at CS exceeds 0.55V. When this occurs, the GATE off-time THICCUP = 550μs is generated to prevent stair-casing of the inductor current and potentially its saturation due to insufficient output voltage. ILED 550mV RCS VCS 550mV t 550us(Typ.) Linear Dimming When the voltage at DIM falls below 1.5V, the internal 250mV reference to the constant-current feedback becomes overridden by VDIM • 0.167. As long as the current in the inductor remains continuous, the LED current is given by the equation above. However, when V DIM falls below 200mV, the GATE output becomes disabled. The GATE signal recovers, when VDIM exceeds 250mV. This is required in some applications to be able to shut the LED lamp off with the same signal input that controls the brightness. LED Current 100% 80% 60% 40% 20% 0% 0.3 0.6 0.9 1.2 1.5 DIM(V) This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 9/14 FP7175 PWM Dimming Due to the fast open-loop response of the average-current control loop of the FP7175, its PWM dimming performance nearly matches that of the FP7171. V LED Current PWM Dimming GATE t The rising and falling edges are limited by the current slew rate in the inductor. The first switching cycle is terminated upon reaching the 250mV (VDIM • 0.167) level at CS. The circuit is further reaching its steady-state within 1 switching cycles regardless of the switching frequency. This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 10/14 FP7175 ※ VIN=12V, LED=9.2V, TA = 25°C, unless otherwise noted Input Voltage VS Frequency 2 100 1.6 80 Frequency(kHz) LED Current(A) Input Voltage VS LED Current 1.2 0.8 60 40 20 0.4 L=100uH 0 0 0 30 60 0 90 30 90 Input Voltage(V) Input Voltage(V) Inductor VS LED Current LED Voltage VS LED Current 2 1.9 1.95 LED Current(A) 1.88 LED Current(A) 60 1.86 1.84 1.82 Vin=24V 2 4 6 8 1.85 1.8 1.75 VIN=12V 1.8 1.9 1.7 10 20 50 LED Voltage(V) 80 110 Inductor(uH) PWM Duty VS LED Current DIM Voltage VS LED Current 2 2 1.8 1.6 LED Current(A) LED Current(A) 1.6 1.2 0.8 1.4 1.2 1 0.8 0.6 0.4 0.4 0.2 PWM=0V~3.3V(500Hz) 0 0 0 0.4 0.8 1.2 1.6 0 20 40 60 80 100 PWM Duty(%) DIM Voltage(V) This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 11/14 FP7175 Suggested Layout LED+ VIN D1 C2 Q1 LED Load L1 GATE VDD FP7175 GND DIM CS VIN LEDC1 R1 GND This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 12/14 FP7175 Typical Application Circuit VIN=11V~100V VIN LED+ C2 0.47uF C1 22uF/100V GATE VDD FP7175 GND D1 SR510VF VLED=3V ~ 9.5V ILED=2A LED- GND DIM CS VIN L1 47uH Q1 12N10 RCS 0.125 This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 13/14 FP7175 Package Outline SOT23-6L Unit: mm Symbols Min. (mm) Max. (mm) A 1.050 1.450 A1 0.050 0.150 A2 0.900 1.300 b 0.300 0.500 c 0.080 0.220 D 2.900 BSC E 2.800 BSC E1 1.600 BSC e 0.950 BSC e1 1.900 BSC L 0.300 0.600 L1 0.600 REF L2 0.250 BSC θ° 0° 8° θ1° 3° 7° θ2° 6° 15° Note: 1. Package dimensions are in compliance with JEDEC outline: MO-178 AB. 2. Dimension “D” does not include molding flash, protrusions or gate burrs. 3. Dimension “E1” does not include inter-lead flash or protrusions. This datasheet contains new product information. Feeling Technology reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sales of the product. Website: http://www.feeling-tech.com.tw Rev. 0.60 14/14