april 2009 fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com fan5336 1.5mhz tinyboost? regulator with 33v integrated fet switch features 1.5mhz switching frequency low noise adjustable output voltage up to 1.5a peak switch current low shutdown current: <1a cycle-by-cycle current limit over-voltage protection at the feedback pin fixed-frequency pwm operation soft-start capability internal compensation thermal shutdown excellent load regulation: 0.2% low ripple 6-lead 3x3mm mlp applications portable displays mobile phone / smart phone led backlights display bias pda, dvd, camcorder backlights pager and cordless phone displays portable medical diagnostic equipment remote controls mp3 or pmp or dsc players serial flash led drivers description the fan5336 is a high-efficiency, low-noise, fixed-fre- quency pwm, current-mode, dc-dc boost regulator. it is designed for small lcd bias supply and white led backlight supply applications. depending on the applica- tion, a fan5336 regulator can output up to 33v at up to 50ma output current. with output voltage up to 21v, the output current can be up to 100ma. fan5336 can be used for power conversion as low as 9v output voltage. a current-mode control loop has a fast transient response that provides excellent load regulation within 0.2% of output voltage. the fan5336 switches at fixed 1.5mhz frequency, allowing the use of small, low-cost external components. constant frequency switching results in low input noise and small output capacitors. fan5336 provides cycle-by-cycle current limiting up to 1.5a peak current. the fan5336 may be used to drive a serial flash led with up to 100ma current at 21v for a maximum of 400ms on-time and 10% duty cycle. a low-emi mode reduces interference and radiated elec- tromagnetic energy caused by the ringing of the inductor. additional features include thermal shutdown, over-volt- age protection, cycle-by-cycle current limit, low ripple, and soft-start support. the device is available in a 3x3mm 6-lead mlp, 0.8mm thickness package. application diagram figure 1. typical application diagram shdn v in v out r1 r2 nc gnd v in p1 fb sw c f c in 6.8h 1 3 2 5 6 4 10f 180pf c out l1 d1 4.7f on off
fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 2 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com ordering information for fairchild?s definition of ?green? eco status, please visit: http://www.fairchildsemi.com/company/green/rohs_green.html . pin assignments figure 2. 6-lead, 3x3mm mlp (top view) pin descriptions part number package temperature range eco status packing method fan5336mpx 6-lead 3x3mm mlp -40c to +85c green tape and reel FAN5336UMPX 6-lead 3x3mm umlp -40c to +85c green tape and reel pin # name description p1 gnd analog and power ground. p1 must be soldered to the pcb ground. 1v in input voltage pin. 2 gnd ground. 3 shdn shutdown control pin. logic high enables, logic low disables the device. 4fb feedback pin. feedback node that connects to an external voltage divider. 5 nc no connect. 6 sw switching node. shdn fb gnd sw vin nc 1 2 3 6 5 4 p1
fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 3 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com absolute maximum ratings stresses exceeding the absolute maximum ratings may damage the device. the device may not function or be opera- ble above the recommended operating conditions and stressing the parts to these levels is not recommended. in addi- tion, extended exposure to stresses above the recommended operating conditions may affect device reliability. the absolute maximum ratings are stress ratings only. note: 1. using eia/jesd22a114b (human body model) and eia/jesd22c101-a (charge device model). recommended operating conditions the recommended operating conditions table defines the conditions for actual device operation. recommended operating conditions are specified to ensure optimal performance to the datasheet specifications. fairchild does not recommend exceeding them or designing to absolute maximum ratings. note: 2. this load capacitance value is required for loop stability. tolerance, temperature variation, and voltage dependency of the capacitance must be considered. typically a 4.7f ceramic capacitor is required to achieve the specified value at v out = 33v. symbols parameter min. max. unit v in v in to gnd 6.0 v fb, shdn to gnd -0.3 v in + 0.3 v sw to gnd -0.3 35 v t l lead soldering temperature (10 seconds) 300 c t j junction temperature 150 c t stg storage temperature -55 150 c ja thermal resistance 265 c/w esd electrostatic discharge protection level (1) hbm 2 kv cdm 1 symbols parameter min. typ. max. unit v in input voltage 2.7 5.5 v v out output voltage 9 33 v t a ambient operating temperature -40 25 85 c c out output capacitance 2.2 (2) 10 f
fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 4 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com electrical characteristics v in = 2.7 to 5.5v, v shdn = v in , and t a = -40c to +85c. typical values are at t a = 25c and v in = 3.6v unless otherwise noted. note: 3.the line regulation is calculated based on . test circuit figure 3. test circuit parameter conditions refer to the test circuit in figure 3. min. typ. max. units output voltage accuracy v in = 3.6v -3 +3 % switch current limit v in = 3.2v 1.1 1.5 1.8 a load current v out = 21v 5%, v in 3.0v 75 ma v out = 21v 5%, v in 3.2v, t on < 0.4s, t off > 3.6s 100 switch on-resistance v in = 3.6v 0.4 quiescent current no switching, v fb 1.27v 0.7 ma switching 6.5 off mode current v shdn = 0v 0.1 3.0 a shutdown threshold device on 1.5 v device off 0.5 shutdown pin bias current v shdn = 0v or v shdn = 5.5v 1 10 na feedback voltage (v ref )i load = 0ma, v in = 3.6v at 25c 1.205 1.230 1.255 v feedback pin bias current 1 10 na feedback voltage line regulation (3) 3.0v < v in < 5.5v, i load = 0ma 0.4 1.5 %/v switching frequency 1.15 1.50 1.85 mhz maximum duty cycle 87 93 % start-up turn-on time v in = 3.0v, i out = 75ma 3.0 5.0 ms load regulation v in = 3.6v, 1ma < i load <100ma 0.2 % switch leakage current no switching, v in = 5.5v 1 a v out v in ------------------ 1 v out -------------- shdn v in v ou t r1 r2 nc gnd v in p1 fb sw c f c in 6.8h 1 3 2 5 6 4 10f 180pf c out l bat54 4.7f 2.7v to 5.5v on off 10k 160k
fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 5 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com typical performance characteristics v in =3.6v, v out =21v, t a =25c, c in =10f, c out =4.7f, l=6.8h, c f =180pf, r 1 =160k , r 2 =10k unless otherwise noted. figure 4. efficiency vs. load current figure 5. load regulation figure 6. line regulation at no load figure 7. 100ma load current operation figure 8. start-up response figure 9. load transient response efficiency vs. load current 40 45 50 55 60 65 70 75 80 85 90 10 20 30 40 50 60 70 80 90 100 load current (ma) efficiency (%) vin=2.7v vin=3.6v vin=5.5v load regulation 20.5 20.7 20.9 21.1 21.3 21.5 10 20 30 40 50 60 70 80 90 100 load current (ma) output voltage (v) vin=2.7v vin=3.6v vin=5.5v line regulation at no load 20 20.2 20.4 20.6 20.8 21 21.2 21.4 21.6 21.8 22 2.533.544.555.5 battery voltage(v) output voltage(v)
fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 6 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com block diagram figure 10. block diagram circuit description the fan5336 is a pulse-width modulated (pwm) current-mode boost converter. the fan5336 improves the performance of battery-powered equipment by significantly minimizing the spectral distribution of noise at the input caused by the switching action of the regula- tor. to facilitate effective noise filtering, the switching frequency was chosen to be high, 1.5mhz. an internal soft-start circuit minimizes in-rush currents. the timing of the soft-start circuit was chosen to reach 95% of the nominal output voltage within 5ms following an enable command when v in = 2.7v, v out = 21v, i load = 35ma and c out (effective) = 4.7f. the device architecture is a current-mode controller with an internal sense resistor connected in series with the n- channel switch. the voltage at the feedback pin tracks the output voltage at the cathode of the external schottky diode (shown in the test circuit in figure 3). the error amplifier amplifies the difference between the feedback voltage and the internal bandgap reference. the ampli- fied error voltage serves as a reference voltage to the pwm comparator. the inverting input of the pwm comparator consists of the sum of two components: the amplified control signal received from the 30m current sense resistor and the ramp generator voltage derived from the oscillator. the oscillator sets the latch and the latch turns on the fet switch. under normal operating conditions, the pwm comparator resets the latch and turns off the fet, terminating the pulse. since the com- parator input contains information about the output volt- age and the control loop is arranged to form a negative feedback loop, the value of the peak inductor current is adjusted to maintain regulation. every time the latch is reset, the fet is turned off and the current flow through the switch is terminated. the latch can be reset by other events as well, such as over- current and over-voltage conditions. over-current condi- tion is monitored by the current-limit comparator, which resets the latch and turns off the switch within each clock cycle. an over-voltage condition at the feedback (fb) pin is detected by a fast comparator limiting the duty cycle in a similar manner to over-current monitoring. n fb fb driver comp comp - - + + r r r q s current limit comparator 0.03 1.15 x v ref shutdown circuitry ramp generator reference soft-start oscillator thermal shutdown shdn gnd sw v in amp error amp 6 1 3 2 4 + + - - + - nc 5
fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 7 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com applications information setting the output voltage the internal feedback voltage reference (v ref ) is 1.23v (typical). the output voltage is divided by a resistor divider, r 1 and r 2 to the fb pin. the output voltage is calculated by: the maximum output current depends on the output volt- age settings. table 1 provides the recommended voltage for several steady-state configurations: table 1: recommended voltages inductor selection the inductor parameters directly related to device perfor- mance are saturation current and dc resistance. the fan5336 operates with a typical inductor value of 6.8h. the lower the dc resistance, the higher the efficiency. balancing inductor size, cost, and overall efficiency allows optimum choice. the inductor saturation current should be rated around 1.5a, which is the threshold of the internal current limit circuit. this limit is reached only during the start-up and with heavy load conditions. when this occurs, the con- verter can shift into discontinuous conduction mode due to the automatic turn-off of the switching transistor, resulting in higher ripple and reduced efficiency. table 2: recommended inductors capacitors selection for best performance, low-esr input and output capaci- tors are required. ceramic capacitors of c in = 10f and c out = 4.7f, placed as close as possible to the ic pins, are recommended for the lower input and output ripple. the output capacitor voltage rating should be selected according to the v out setting. table 3: recommended capacitors a feedforward capacitor (c f ) is required for stability. the recommended value is around 180pf. diode selection the external diode used for rectification is usually a schottky diode. its average forward current should exceed the load current and its reverse voltage maxi- mum ratings should exceed the voltage at the output of the converter. a barrier schottky diode, such as bat54, is preferred due to its low reverse current over the temperature range. care should be taken to avoid any short circuit of v out to gnd, even with the ic disabled, since the diode can be instantly damaged by the excessive current. flash led driver the fan5336 may be used to drive a serial flash led with up to 100ma current at 21v for a maximum of 400ms on-time and 10% duty cycle. thermal shutdown when the die temperature exceeds 150c, a reset occurs and remains in effect until the die cools to 130c, when the circuit is allowed to restart. pcb layout recommendations the inherently high peak currents and switching fre- quency of power supplies require careful pcb layout design. for best results, use wide traces for high-current paths and place the input capacitor, the inductor, and the output capacitor as close as possible to the integrated circuit terminals. the resistor divider that sets the output voltage should be routed away from the inductor to avoid rf coupling. a four-layer pcb, with at least one ground plane connected to pin 2 of the ic, is recommended. the ground plane acts as an electromagnetic shield to reduce emi and parasitic coupling between components. figure 11. recommended pcb layout v out (v) i load max. (ma) r 1 (k ) for r 2 = 10k v in range (v) 9 50 63.2 2.7 to 5.5 9 170 63.2 2.9 to 4.7 12 125 87.5 2.7 to 5.5 21 75 160 3.6 to 5.5 33 50 258 4.0 to 5.5 33 10 258 2.7 to 5.5 inductor value vendor part number comment 6.8h tdk slf7028t6r8m1r3 lower profile 6.8h murata lqs66c6r8m04 higher efficiency v out v ref 1 r 1 r 2 ------ - + ?? ?? ?? ?? = eq 1 cap. value vendor part number 10f murata grm31cr70j106ka01b 4.7f murata grm32rr61e475kc31b
fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 8 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com physical dimensions figure 12. 6-lead 3x3 molded leadless package (mlp) package drawings are provided as a servic e to customers considering fairchild co mponents. drawings may change in any manner without notice. please note the revision and/or date on the drawi ng and contact a fairchild semic onductor representative to ver ify or obtain the most recent revision. package specifications do not expand the terms of fairchild?s worldwide terms and conditions, specifically the warranty therein, which covers fairchild products. always visit fairchild semiconductor?s online packagi ng area for the most recent package drawings: http://www.fairchildsemi.com/packaging/ .
fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 9 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com physical dimensions figure 12. 6-lead 3x3 ultrathin molded leadless package (umlp) package drawings are provided as a servic e to customers considering fairchild co mponents. drawings may change in any manner without notice. please note the revision and/or date on the drawi ng and contact a fairchild semic onductor representative to ver ify or obtain the most recent revision. package specifications do not expand the terms of fairchild?s worldwide terms and conditions, specifically the warranty therein, which covers fairchild products. always visit fairchild semiconductor?s online packagi ng area for the most recent package drawings: http://www.fairchildsemi.com/packaging/ . b. dimensions are in millimeters. c. dimensions and tolerances per a. conforms to jedec registration mo-229, variation veea, dated 8/2003, except thickness asme y14.5m, 1994 0.10 cab 0.05 c 0.15 c 0.08 c b a c 3.0 3.0 0.05 0.00 2.00 1.21 1.90 0.15 c 2x 2x 0.45 0.20 0.6 max seating plane 2.10 1.65 2.45 0.65 typ 0.95 typ 3.50 0.10 c pin #1 ident 1 3 4 6 13 4 6 (0.70) 0.30~0.45 0.2 min (0.20) 0.95 d. filename and revision: umlp06arev1
fan5336 ? 1.5mhz tinyboost? regulator with 33v integrated fet switch fan5336 rev. 1.0.2 10 ? 2004 fairchild semiconductor corporation www.fairchildsemi.com
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