LT3517HUF LINEAR_DIMENSIONS | Alldatasheet
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Technical content
For more information www.linear .com/L T3517
FEATURES
APPLICATIONS
DESCRIPTION
with 1.5A Switch Current The LT®3517 is a current mode DC/DC converter with an internal 1.5A, 45V switch specifically designed to drive LEDs. The L T3517 operates as a LED driver in boost, buck mode and buck-boost mode. It combines a tradi - tional voltage loop and a unique current loop to operate as a constant-current source or constant-voltage source. Programmable switching frequency allows optimization of the external components for efficiency or component size. The switching frequency of L T3517 can be synchronized to an external clock signal. The LED current is externally programmable with a 100mV sense resistor. The external PWM input provides up to 5000:1 LED dimming. The CTRL pin provides further 10:1 dimming ratio. The L T3517 is available in the tiny footprint 16-lead QFN (4mm × 4mm) and the 16-pin TSSOP packages. The L T3517 provides a complete solution for both constant- voltage and constant-current applications. ■ 5000:1 True Color PWM™ Dimming Ratio ■ 1.5A, 45V Internal Switch ■ 100mV High Side Current Sense ■ Open LED Protection ■ Adjustable Frequency: 250kHz to 2.5MHz ■ Wide Input Voltage Range: Operation from 3V to 30V Transient Protection to 40V ■ Operates in Boost, Buck Mode and Buck-Boost Mode ■ Gate Driver for PMOS LED Disconnect ■ Constant-Current and Constant-Voltage Regulation ■ CTRL Pin Provides 10:1 Analog Dimming ■ Low Shutdown Current: <1µA ■ Available in (4mm × 4mm) 16-Lead QFN and 16-Pin TSSOP Packages ■ Display Backlighting ■ Automotive and Avionic Lighting ■ Illumination ■ Scanners 10µF 15µH 2.2µF 0.1µF 100m/uni03A9 2.2µF VREF ISP TGEN GNDVREF VC 16.9k 1MHz
3517 TA01a
0.1µF VIN SHDN CTRL PWM SYNC FB SS RT SW PV IN 24V VIN 3.3V ISN L T3517 TG PWM 1A Buck Mode LED Driver Efficiency PWM DUTY CYCLE (%) EFFICIENCY (%) 100 20 40 60 80
3517 TA01b
CTRL = VREF L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks and True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 7199560, 7321203, 7746300. TYPICAL APPLICATION
For more information www.linear .com/L T3517 ABSOLUTE MAXIMUM RATINGS Operating Junction Temperature Range (Notes 2,4) (Note 1) PIN CONFIGURATION ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE L T3517EUF#PBF L T3517EUF#TRPBF 3517 16-Lead (4mm × 4mm) Plastic QFN –40°C to 125°C L T3517IUF#PBF L T3517IUF#TRPBF 3517 16-Lead (4mm × 4mm) Plastic QFN –40°C to 125°C L T3517HUF#PBF L T3517HUF#TRPBF 3517 16-Lead (4mm × 4mm) Plastic QFN –40°C to 150°C L T3517EFE#PBF L T3517EFE#TRPBF 3517FE 16-Lead Plastic TSSOP –40°C to 125°C L T3517IFE#PBF L T3517IFE#TRPBF 3517FE 16-Lead Plastic TSSOP –40°C to 125°C L T3517HFE#PBF L T3517HFE#TRPBF 3517FE 16-Lead Plastic TSSOP –40°C to 150°C Consult L TC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container Consult L TC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear .com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear .com/tapeandreel/ Storage Temperature Range Lead Temperature (Soldering, 10 sec) FE PACKAGE 16-LEAD PLASTIC TSSOP TOP VIEW V IN SHDN VREF RT SYNC SS PWM CTRL SW SW TG ISP ISN TGEN FB VC TJMAX = 150°C, θJA = 40°C/W, θJC(PAD) = 10°C/W 16 15 14 13 5 6 7 8 TOP VIEW GND UF PACKAGE 16-LEAD (4mm × 4mm) PLASTIC QFN 1 SW SW V IN SHDN FB VC CTRL PWM TG ISP ISN TGEN V REF RT SYNC SS TJMAX = 125°C, θJA = 36°C/W EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
For more information www.linear .com/L T3517
ELECTRICAL CHARACTERISTICS
PARAMETER CONDITIONS MIN TYP MAX UNITS Minimum VIN Operating Voltage 3 V Maximum VIN Operating Voltage Continuous Operation (Note 3) 30 V Current Sense Voltage (VISP – VISN) VCTRL = 2V, VISP = 24V, VC = 1V VCTRL = 2V, VISP = 0V, VC = 1V
- 96 100 100 103 mV mV 10% Scale Current Sense Voltage (V ISP – VISN) VCTRL = 100mV, VISP = 24V, VC = 1V 9 mV Current Sense Voltage Line Regulation 2V < VISP < 45V 0.03 %/V VIN Supply Current PWM > 1.5V, VC = 0V PWM = 0V SHDN = 0V 4.5 0.1 mA mA µA Switching Frequency R T = 16.7k RT = 4.03k RT = 91.5k
- 0.85 2.25 220 2.5 250 1.15 2.7 270 MHz MHz kHz RT Voltage 1 V Soft-Start Pin Current SS = 0.5V, Out of Pin 6 9 12 µA SYNC Pull-Down Current (Into the Pin) V SYNC = 2V 60 µA SYNC Input Low 0.4 V SYNC Input High 1.5 V Maximum Duty Cycle RT = 91.5k (250kHz) SYNC = 300kHz Clock Signal, RT = 91.5k RT = 16.7k (1MHz) RT = 4.03k (2.5MHz) Switch Current Limit 1.5 1.9 2.3 A Switch V CESAT ISW = 1A 300 mV Switch Leakage Current VSW = 45V, PWM = 0V 2 µA CTRL Input Bias Current Current Out of Pin, VCTRL = 0.1V 20 100 nA Error Amplifier T ransconductance 550 µS VC Output Impedance 1000 kΩ VC Idle Input Bias Current PWM = 0V, VC = 1V –20 0 20 nA FB Pin Input Bias Current Current Out of Pin, VFB = 0.5V 20 100 nA FB Pin Threshold ● 0.98 1.01 1.04 V ISP , ISN Idle Input Bias Current PWM = 0V , ISP = ISN = 24V 300 nA ISP , ISN Full-Scale Input Bias Current ISP Tied to ISN, VISP = 24V, VCTRL = 2V 20 µA SHDN Voltage High ● 1.2 V SHDN Voltage Low –40°C ≤ TJ ≤ 125°C 125°C < TJ ≤ 150°C 0.45 0.40 V V SHDN Pin Bias Current 60 100 µA PWM Input High Voltage
- 1.2 V PWM Input Low Voltage –40°C ≤ TJ ≤ 125°C 125°C < TJ ≤ 150°C 0.45 0.40 V V PWM Pin Bias Current 60 120 µA The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 2) VIN = 5V , SHDN = 5V , PWM = 5V unless otherwise noted.
For more information www.linear .com/L T3517 The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 2) VIN = 5V , SHDN = 5V , PWM = 5V unless otherwise noted. TYPICAL PERFORMANCE CHARACTERISTICS VISP – VISN Threshold vs VCTRL Switch Current Limit vs Duty Cycle Oscillator Frequency vs RT VCTRL (V) VISP – VISN THRESHOLD (mV) 0.4 0.8 1.2 1.6
3518 G01
0.2 0.6 1.0 1.4 VIN = 5V VISP = 24V VC = 1V TA = 25°C RT (k/uni03A9)
100 OSCILLATOR FREQUENCY (kHz)
3518 G03
TA = 25°C DUTY CYCLE (%) SWITCH CURRENT LIMIT (A)0.5 1.0 1.5 2.0 20 40 60 80
3517 G02
TA = 25°C Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The L T3517E is guaranteed to meet performance specifications from 0°C to 125°C operating junction temperature range. Specifications over the –40°C to 125°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls. The L T3517I is guaranteed over the full –40°C to 125°C operating junction temperature range. The L T3517H is guaranteed over the full –40°C to 150°C operating junction temperature range. Operating lifetime is derated at junction temperatures greater than 125°C. PARAMETER CONDITIONS MIN TYP MAX UNITS TGEN Input High Voltage 1.5 V TGEN Input Low Voltage 0.4 V TGEN Pin Bias Current TGEN = 5V 100 200 µA VREF Pin Voltage IREF = –100µA ● 1.96 2 2.04 V VREF Pin Voltage Line Regulation 3V < VIN < 40V 0.03 %/V Gate Turn-On Delay CLOAD = 1nF Between ISP and TG 200 ns Gate Turn-Off Delay CLOAD = 1nF Between ISP and TG 200 ns Top Gate Drive VGS (VISP – VTG) VISP = 24V , TGEN = 5V PWM = 0V 0.3 V V Note 3: Absolute maximum voltage at VIN, SHDN, PWM and TGEN pins is 40V for nonrepetitive 1 second transients and 30V for continuous operation. Note 4: This IC includes overtemperature protection that is intended to protect the device during momentary overload conditions. Junction temperature will exceed the maximum operating junction temperature when overtemperature protection is active. Continuous operation above the specified maximum operating junction temperature may impair device reliability.
For more information www.linear .com/L T3517 VISP – VISN Threshold vs Temperature Switch Current Limit vs Temperature Oscillator Frequency vs Temperature Reference Voltage vs Temperature Quiescent Current vs V IN TEMPERATURE (°C) –40 VISP – VISN THRESHOLD (mV) 103
3517 G04
–20 0 40 104 102 101 60 80 100 120 140 160 VIN = 5V VISP = 24V VC = 1V VCTRL = 2V TEMPERATURE (°C) –40 –20 1.5 OSCILLATOR FREQUENCY (MHz) 1.9 2.5 0 40 60
3517 G06
1.7 2.3 2.1 20 80 160100 120 140 VIN = 5V RT = 6.04k VISP (V) VISP – VISN THRESHOLD (mV) 101 103 105
3517 G07
VCTRL = 2V VIN = 5V TA = 25°C VC = 1V TEMPERATURE (°C) –40
1.98 VREF (V)
1.99 2.00 2.01 2.02 –20 0 20 40
3517 G08
VIN = 5V VIN (V) VIN CURRENT (mA)
3517 G09
TA = 25°C VC = 0V VISP – VISN Threshold vs VISP TYPICAL PERFORMANCE CHARACTERISTICS FB Pin Threshold vs Temperature PMOS Turn-On PMOS Turn-Off TEMPERATURE (°C) –40
0.98 FB PIN THRESHOLD (V)
1.00 0.99 1.01 1.03 1.02 1.04 –20 0 20 40
3517 G10
VIN = 5V PWM 40V TG 30V 200ns/DIVVISP = 40V
3517 G11
200ns/DIVVISP = 40V TEMPERATURE (°C) –40 –20 SWITCH CURRENT LIMIT (A) 1.0 2.5 0 40 60
3518 G05
0.5 2.0 1.5 20 80 100 120 140 160 VIN = 5V
For more information www.linear .com/L T3517 PIN FUNCTIONS SW: Switch Pin. Minimize trace at this pin to reduce EMI. VIN: Input Supply Pin. Must be locally bypassed. SHDN: Shutdown Pin. Tie to 1.5V or higher to enable device or 0.4V or less to disable device. VREF: Reference Output Pin. This pin can supply up to 100µA. RT : Switching Frequency Adjustment Pin. Set switching frequency using a resistor to GND (see Typical Performance Characteristics for values). For SYNC function, choose the resistor to program a frequency 20% slower than the SYNC pulse frequency. Do not leave this pin open. SYNC: Frequency Synchronization Pin. Tie an external clock signal here. R T resistor should be chosen to pro- gram a switching frequency 20% slower than SYNC pulse frequency. Synchronization (power switch turn-on) occurs a fixed delay after the rising edge of SYNC. Tie the SYNC pin to ground if this feature is not used. SS: Soft-Start Pin. Place a soft-start capacitor here. Leave the pin open if not in use. PWM: Pulse Width Modulated Input Pin. Signal low turns off channel, disables the main switch and makes the TG pin high. Tie the PWM pin to V REF pin or SHDN pin if not used. There is an equivalent 50k resistor from PWM pin to ground internally. CTRL: LED Current Adjustment Pin. Sets voltage across sense resistor between ISP and ISN. Connect directly to V REF for full-scale threshold of 100mV, or use signal values between GND and 1V to modulate LED current. Tie the CTRL pin to the V REF pin if not used. VC: gm Error Amplifier Output Pin. Stabilize the loop with an RC network or compensating C. FB: Voltage Loop Feedback Pin. Works as overvoltage protection for LED drivers. If FB is higher than 1V, the main switch is turned off. TGEN: Top Gate Enable Input Pin. Tie to 1.5V or higher to enable the PMOS driver function. Tie the TGEN pin to ground if TG function is not used. There is an equivalent 40k resistor from TGEN pin to ground internally. ISN: Current Sense (–) Pin. The inverting input to the current sense amplifier. ISP: Current Sense (+) Pin. The noninverting input to the current sense amplifier. Also serves as positive rail for TG pin driver. TG: Top Gate Driver Output. An inverted PWM sig - nal drives series PMOS device between V ISP and (VISP – 7V). An internal 7V clamp protects the PMOS gate. Leave TG unconnected if not used. GND: Exposed Pad (QFN Package). Solder paddle directly to ground plane.
3517 F01
Figure 1. Buck Mode LED Driver
For more information www.linear .com/L T3517 OPERATION The L T3517 is a constant frequency, current mode regula- tor with an internal power switch. Operation can be best understood by referring to the Block Diagram in Figure 1. At the start of each oscillator cycle, the SR latch is set, which turns on the Q1 power switch. A voltage proportional to the switch current is added to a stabilizing ramp and the resulting sum is fed into the positive terminal of the PWM comparator, A4. When this voltage exceeds the level at the negative input of A4, the SR latch is reset, turning off the power switch. The level at the negative input of A4 is set by the error amplifier A3. A3 has two inputs, one from the voltage feedback loop and the other one from the current loop. Whichever feedback input is lower takes precedence, and forces the converter into either constant-current or constant-voltage mode. The L T3517 is designed to transi- tion cleanly between these two modes of operation. The current sense amplifier senses the voltage across R SENSE and provides a pre-gain to amplifier A1. The output of A1 is simply an amplified version of the difference between the voltage across R SENSE and the lower of V CTRL/10 or 100mV. In this manner, the error amplifier sets the correct peak switch current level to regulate the current through R SENSE. If the error amplifier’s output increases, more current is delivered to the output; if it decreases, less current is delivered. The current regulated in RSENSE can be adjusted by changing the input voltage V CTRL. The current sense amplifier provides rail-to-rail current sense operation. The FB voltage loop is implemented by the amplifier A2. When the voltage loop dominates, the error amplifier and the amplifier A2 regulate the FB pin to 1.01V (constant-voltage mode). Dimming of the LED array is accomplished by pulsing the LED current using the PWM pin. When the PWM pin is low, switching is disabled and the error amplifier is turned off so that it does not drive the VC pin. Also, all internal loads on the VC pin are disabled so that the charge state of the VC pin will be saved on the external compensation capacitor . This feature reduces transient recovery time. When the PWM input again transitions high, the demand current for the switch returns to the value just before PWM last transitioned low. To further reduce transient recovery time, an external PMOS is used to disconnect the LED array current loop when PWM is low, stopping C FIL T from discharging. APPLICATIONS INFORMATION Dimming Control There are two methods to control the current source for dimming using the L T3517. The first method uses the PWM pin to modulate the current source between zero and full current to achieve a precisely programmed aver- age current. To make this method of current control more accurate, the switch demand current is stored on the VC node during the quiescent phase. This feature minimizes recovery time when the PWM signal goes high. To further improve the recovery time, a disconnect switch is used in the LED current path to prevent the output capacitor from discharging in the PWM signal low phase. The minimum PWM on or off time will depend on the choice of operating frequency through RT input pin or SYNC pin. When us - ing the SYNC function, the SYNC and PWM signals must have the aligned rising edges to achieve the optimized high PWM dimming ratio. For best current accuracy, the minimum PWM low or high time should be at least four switching cycles (2µs for f SW = 2MHz). Maximum PWM period is determined by the system and is unlikely to be longer than 12ms. The maximum PWM dimming ratio (PWM RATIO) can be calculated from the maximum PWM period (tMAX) and the minimum PWM pulse width (tMIN) as follows: PWMRATIO = tMAX tMIN (1) Example: tMAX = 10ms, tMIN = 2µs (fSW = 2MHz) PWMRATIO = 10ms/2µs = 5000:1 The second method of dimming control uses the CTRL pin to linearly adjust the current sense threshold during the PWM high state. When the CTRL pin voltage is less
For more information www.linear .com/L T3517 APPLICATIONS INFORMATION than 1V , the LED current is: ILED = VCTRL 10 •RSENSE (2) When VCTRL is higher than 1V , the LED current is clamped to be: ILED = 100mV RSENSE (3) The LED current programming feature possibly increases total dimming range by a factor of ten. The CTRL pin should not be left open (tie to V REF if not used). The CTRL pin can also be used in conjunction with a PTC thermistor to provide overtemperature protection for the LED load. For a buck or a buck-boost configuration, the output voltage is typically level-shifted to a signal with respect to GND, as illustrated in the Figure 4. The output can be expressed as: VOUT = R1 R2 •1.01V+ VBE(Q1) (5) 49.9k
3517 F02
45.3k 2VVREF PTC CTRL Figure 2 Setting Output Voltage For a boost application, the output voltage can be set by selecting the values of R1 and R2 (see Figure 3) according to the following equation: VOUT = R1 R2 + 1 •1.01V (4) L T3517 FB VOUT
3517 F03
3517 F04
The inductor used with the L T3517 should have a satura- tion current rating of 2A or greater. For buck mode LED drivers, the inductor value should be chosen to give a ripple current “ΔI” of ~30% to 40% of the LED current. In the buck mode, the inductor value can be estimated using the formula: L µH( ) = DBUCK •tSW (µs)• VIN – VLED( ) ΔI DBUCK = VLED VIN (6) VLED is the voltage across the LED string, VIN is the input voltage to the converter, and tSW is the switching period. In the boost configuration, the inductor can be estimated using the formula: L µH( ) = DBOOST •tSW (µs)•VIN ΔI DBOOST = VLED – VIN VLED (7)
Table 1 provides some recommended inductor vendors. Table 1. Inductor Manufacturers ceramic capacitor is usually the best choice. capacitor is usually sufficient. and converter configuration, i.e., step-up or step-down. sized to attenuate the current ripple. the LED voltage during PWM transitions. check that the voltage rating of the capacitor is sufficient. Table 2 shows some recommended capacitor vendors. Table 2. Ceramic Capacitor Manufacturers tion resistor and capacitor determine the loop stability. recommended component vendors.
Table 3. Schottky Diodes resistor values and corresponding switching frequencies. Table 4. Switching Frequency vs RT external clock when external clock is absent.
For more information www.linear .com/L T3517 Buck Mode 1A LED Driver 2000:1 PWM Dimming at 120Hz 350mA, 5V to 12V Boost Converter with Accurate Input Current Limit 10µF 15µH 2.2µF 0.1µF RSENSE 100m/uni03A9 M1 2.2µF ISP TGEN GNDVREF VC RT 16.9k 1MHz
3517 TA02a
0.1µF C1: KEMET C0805C225K4RAC C2: MURATA GRM31MR71E225KA93 C3: MURATA GRM32DR71E106KA12B C4, C5: MURATA GRM21BR71H104KA01B D1: DIODES DFLS160 L1: TOKO B992AS-150M LEDS: LUXEON K2 (WHITE) M1: ZETEX ZXMP6A13FTA V IN SHDN CTRL PWM SYNC FB SS RT SW PV IN 24V VIN 3.3V ISN L T3517 TG PWM VREF SW VC GND SS VIN CTRL PWM SHDN TGEN V REF FB VOUT 12V 350mA VIN SYNC 549k 10µF 0.1µFC4 10nF SHDN RT ISN L T3517 TG ISP 49.9k R T 6.04k 2MHz 10k
3517 TA03a
2.2µF 6.8µH R SENSE 100m/uni03A9 C1: KEMET C0805C225K4RAC C2: KEMET C1206C106K4RAC C3: MURATA GRM21BR71H104KA01B C4: MURATA GCM033R71A103KA03 D1: ZETEX ZLLS1000TA L1: TOKO B992AS-6R8N Efficiency TYPICAL APPLICATIONS ILOAD(mA) EFFICIENCY (%) 100 150 200 250
3517 TA03b
1µs/DIV PVIN = 24V fOSC = 1MHz ILED = 1A
3517 TA02b
For more information www.linear .com/L T3517 5000:1 PWM Dimming at 100Hz Efficiency Buck-Boost Mode LED Driver 6.8µH RSENSE 330m/uni03A9 SHDN VC GNDRT SS RT 6.04k 2MHz
3517 TA04aC3
0.1µF 4.7µF 3.92M 124k 0.22µF 2.2µF 0.1µF PWM ISP FB ISN TG TGEN VREF CTRL SYNC 300mA VIN 8V TO 16V VIN L T3517 SW PWM C1: KEMET C0806C225K4RAC C2: KEMET C1206C475K3RAC C3, C4: MURATA GRM21BR71H104KA01B C5: MURATA GRM21BR71H224KA01B D1: DIODE DFLS160 L1: TOKO B992AS-6R8N LEDS: LUXEON I (WHITE) M1: ZETEX ZXMP6A13FTA TYPICAL APPLICATIONS PWM DUTY CYCLE (%) EFFICIENCY (%) 20 40 60 80
3517 TA04c
VIN = 12V CTRL = VREF PWM 5V/DIV IL 1A/DIV ILED 200mA/DIV 500ns/DIV VIN = 12V fOSC = 2MHz ILED = 300mA
3517 TA04b
For more information www.linear .com/L T3517 Low Side Current Sensing Load Dump Protected Buck-Boost Mode LED Driver 6.8µH RSENSE 330m/uni03A9 SHDN VC GNDRT SS RT 6.04k 2MHz 10k
3517 TA05a
0.1µF 4.7µF 3.92M 124k 0.22µF 2.2µF 33nF PWM ISP FB ISN TG TGEN VREF CTRL SYNC 300mA VIN 8V TO 16V VIN L T3517 SW PWM D1: DIODES DFLS160 L1: TOKO B992AS-6R8N C1: KEMET C0806C225K4RAC C2: KEMET C1206C475K3RAC C3: MURATA GRM21BR71H104KA01B C4: MURATA GRM219R71H333KAQ01B C5: MURATA GRM21BR71H224KA01B M1: ZETEX ZXMP6A13FTA LEDs: LUXEON I (WHITE) TYPICAL APPLICATIONS 5000:1 PWM Dimming at 100Hz Efficiency PWM 5V/DIV IL 1A/DIV ILED 200mA/DIV 500ns/DIV VIN = 12V fOSC = 2MHz ILED = 300mA
3517 TA05b
PWM DUTY CYCLE (%) EFFICIENCY (%) 20 40 60 80
3517 TA05c
VIN = 12V CTRL = VREF VISP REF GND 5ms/DIV VIN Raises From 15V to 40V in 5ms.
3517 TA05d
For more information www.linear .com/L T3517 TYPICAL APPLICATIONS Boost 100mA LED Driver with LED Open Protection LED1 LED2 LED10 22µH RSENSE 1/uni03A9 30.1k SHDN VC GNDRT SS RT 16.9k 1MHz
3517 TA06a
0.1µF 2.2µF 2.2µF 0.1µF PWM ISP ISN TG FB TGEN VREF CTRL SYNC 100mA VIN 8V TO 16V VIN L T3517 SW PWM C1, C2: KEMET C1206C225K2RAC C3, C4: MURATA GRM21BR71H104KA01B D1: DIODES DFLS160 L1: COILCRAFT DS3316P-223 LEDS: CREE XLAMP 7090 M1: ZETEX ZXMP6A13FTA 3000:1 PWM Dimming at 100Hz Efficiency PWM DUTY CYCLE (%) EFFICIENCY (%) 20 40 60 80
3517 TA06c
VIN = 12V CTRL = VREF PWM 5V/DIV IL 500mA/DIV ILED 100mA/DIV 1µs/DIV VIN = 12V fOSC = 1MHz ILED = 100mA
3517 TA06b
For more information www.linear .com/L T3517 5.5V SEPIC Converter with Short-Circuit Protection SW VC GND SS CTRL SYNC SHDN TGEN V REF FB TG ISP ISN RT VOUT 5.5V 350mA VIN 221k 10µF 10µF 0.1µFC4 10nF SHDN PWM L T3517 V IN 49.9k R T 6.04k 2MHz 10k
3517 TA07a
2.2µF 4.3µH 4.3µH R SENSE 0.22/uni03A9 C1: KEMET C0805C225K4RAC C2, C5: KEMET C1206C106K4RAC C3: MURATA GRM21BR71H104KA01B C4: MURATA GCM033R71A103KA03 D1: ZETEX ZLLS1000TA L1, L2: TOKO B992AS-4R3N Efficiency TYPICAL APPLICATION ILOAD (mA) EFFICIENCY (%) 50 100 150 200
3517 TA07b
For more information www.linear .com/L T3517 PACKAGE DESCRIPTION 4.00 ±0.10 (4 SIDES) NOTE: 1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE MO-220 VARIATION (WGGC) 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE PIN 1 TOP MARK (NOTE 6) 0.55 ±0.20 16 15 BOTTOM VIEW—EXPOSED PAD 2.15 ±0.10 (4-SIDES) 0.75 ±0.05 R = 0.115 TYP 0.30 ±0.05
0.65 BSC
0.200 REF
0.00 – 0.05 (UF16) QFN 10-04 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 0.72 ±0.05 0.30 ±0.05 2.15 ±0.05 (4 SIDES)2.90 ±0.05 4.35 ±0.05 PACKAGE OUTLINE PIN 1 NOTCH R = 0.20 TYP OR 0.35 × 45° CHAMFER 16-Lead Plastic QFN (4mm × 4mm) (Reference LTC DWG # 05-08-1692 Rev Ø)
For more information www.linear .com/L T3517 PACKAGE DESCRIPTION FE16 (BA) TSSOP REV I 0211 0.09 – 0.20 (.0035 – .0079) 0° – 8° 0.25 REF 0.50 – 0.75 (.020 – .030) 4.30 – 4.50* (.169 – .177) 1 3 4 5 6 7 8 10 9 4.90 – 5.10* (.193 – .201) 16 1514 13 12 11 1.10 (.0433) MAX 0.05 – 0.15 (.002 – .006) 0.65 (.0256) BSC 2.74 (.108) 2.74 (.108) 0.195 – 0.30 (.0077 – .0118) TYP MILLIMETERS (INCHES) *DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.150mm (.006") PER SIDE NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE IN RECOMMENDED SOLDER PAD LAYOUT 3. DRAWING NOT TO SCALE 0.45 ±0.05 4.50 ±0.10 6.60 ±0.10 1.05 ±0.10 2.74 (.108) 2.74 (.108) SEE NOTE 4 4. RECOMMENDED MINIMUM PCB METAL SIZE FOR EXPOSED PAD ATTACHMENT 6.40 (.252) BSC 16-Lead Plastic TSSOP (4.4mm) (Reference LTC DWG # 05-08-1663 Rev I) Exposed Pad Variation BA
For more information www.linear .com/L T3517 Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However , no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
REVISION HISTORY
REV DATE DESCRIPTION PAGE NUMBER C 4/10 Added H-grade to Order Information Section 2 D 7/10 Added conditions to ISP , ISN Idle Input Bias Current parameters 3 Changed VIN current sense to 9µA in Figure 1 7 E 01/11 Updated Electrical Characteristics 3 F 04/12 Subscript added to VC Pin Label RT changed to RT in ABS Max Table, QFM Max Temp changed to 150°C Added Operating in Note 2 Clarified Application Schematics Package Diagram Updated 15, 16 G 04/13 Clarified Application schematic 15 (Revision history begins at Rev C)
For more information www.linear .com/L T3517 LINEAR TECHNOLOGY CORPORATION 2007 LT 0413 REV G • PRINTED IN USA Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear .com/L T3517 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS L T1618 Constant Current, 1.4MHz, 1.5A Boost Converter VIN: 5V to 18V, VOUT(MAX) = 36V, Dimming = Analog/PWM, ISD < 1µA, L T3003 3-Channel LED Ballaster with PWM Dimming VIN: 3V to 48V, Dimming = 3000:1 True Color PWM, ISD < 5µA, L T3474 36V , 1A (ILED), 2MHz, Step-Down LED Driver VIN: 4V to 36V, VOUT(MAX) = 13.5V, Dimming = 400:1 True Color PWM, ISD < 1µA, TSSOP16E Package L T3475 Dual 1.5A (ILED), 36V 2MHz Step-Down LED Driver VIN: 4V to 36V, VOUT(MAX) = 13.5V, Dimming = 3000:1 True Color PWM, ISD < 1µA, TSSOP20E Package L T3476 Quad-Output 1.5A, 36V, 2MHz High Current LED Driver with 1000:1 Dimming VIN: 2.8V to 16V, VOUT(MAX) = 36V, Dimming = 1000:1 True Color PWM, ISD < 10µA, 5mm × 7mm QFN Package L T3477 3A, 42V, 3MHz Boost, Buck-Boost, Buck LED Driver VIN: 2.5V to 25V, VOUT(MAX) = 40V, Dimming = Analog/PWM, ISD < 1µA, QFN, TSSOP20E Packages L T3478/L T3478-1 4.5A, 42V, 2.5MHz High Current LED Driver with 3000:1 Dimming V IN: 2.8V to 36V, VOUT(MAX) = 42V, Dimming = 3000:1 True Color PWM, ISD < 3µA, TSSOP16E Packages L T3479 3A, Full -Featured DC/DC Converter with Soft-Start and Inrush Current Protection V IN: 2.5V to 24V, VOUT(MAX) = 40V, IQ = 6.5mA, ISD < 1µA, DFN and TSSOP Packages L T3486 Dual 1.3A, 2MHz High Current LED Driver VIN: 2.5V to 24V, VOUT(MAX) = 36V, Dimming = 1000:1 True Color PWM, ISD < 1µA, 5mm × 3mm DFN, TSSOP16E L T3496 T riple-Output LED Driver VIN: 3V to 40V, VOUT(MAX) = 45V, Dimming = 3000:1 True Color PWM, ISD < 10µA, 4mm × 5mm QFN Package L T3518 Full-Featured LED Driver with 2.3A Switch Current VIN: 3V to 40V, VOUT(MAX) = 45V, Dimming = 3000:1 True Color PWM, ISD < 1µA, 4mm × 4mm QFN Package and TSSOP Package L T3590 48V Buck Mode 50mA LED Driver VIN: 4.5V to 55V, Drives Up to 10 LEDs, 200:1 Dimming, ISO = 15mA, 2mm × 2mm DFN SC70 L T3595 16-Channel Buck LED Driver Mode VIN: 4.5V to 45V, Drives Up to 160 LEDs, 5000:1 Dimming, 5mm × 9mm QFN LT C®3783 High Current LED Controller VIN: 3V to 36V, VOUT(MAX) = Ext FET, Dimming = 3000:1 T rue Color PWM, ISD < 20µA, 5mm × 4mm QFN10, TSSOP16E Packages