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ap 3 4 36/a document number: ds 37212 rev. 2 - 2 1 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated 3a, 1.25mhz high performance synchronous buck converter description the a p3436/a is a step - down dc - dc converter with integrated power stage capable of driving up to 3a continuous output current. it integrates 2 n - channel power mosfets with low on - resistance. current mode control provides fast transient response and cycle - by - cycle current limit. for AP3436, the regulator adopts current - mode in forced pulse - width modulation (pwm) mode with 1.25mhz switching frequency internally, which allow s small - sized components, such as capacitors and inductors. this feature greatly simplifies the design of switch - mode power supplies. under pwm mode, the device remains at the fixed pwm operation (typical at 1.25mhz), regardless of if the load current is h igh or low. for AP3436a, the regulator operates in either fixed pwm mode or a pulse - skipping modulation (psm) mode depending on the different load conditions. the device can operate at typical 1.25mhz fixed switching frequency under heavy load condition. at light load, the regulator enters a psm mode to minimize the switching loss by reducing the switching frequency. the AP3436 /a provides en function. pulling this pin high statically enables the device while pulling the pin low statically for longer than 10 s will shut it down. under v oltage l ockout is internally set at 2. 75 v for v cc detection. the output voltage startup ramp is controlled by the soft start. an open drain power good signal indicates the output is within 75 % to 12 5 % of its nomin al voltage. the AP3436/a is avail able in u - dfn 3 0 3 0 - 10 package. applications ? desktop & notebook ? low voltage, high density power system ? consumer application such as set t op box, lcd display and cpe equipment pin assignments (top view) u - dfn 3 0 3 0 - 10 f eatures ? analog power input v cc range: 3.0v to 5.5v ? power input v in range: 1.3v to 5.5v ? 0.6v reference voltage with 1.5% precision ? 2 mosfets (typ 50m ? ) for high efficiency at 3a loads ? high efficiency: up to 95% ? output current: 3a ? current mode control ? built - in soft start function ? uv and ov power good output ? built - in uv and ov protection function ? built - in over current protection ? built - in thermal shutdow n function ? thermally enhanced 3mm3mm dfn package ? totally lead - free & fully rohs compliant (notes 1 & 2) ? halogen and antimony free. green device (note 3 ) note s: 1 . no purposely added lead. fully eu directive 2002/95/ec (rohs) & 2011/65/eu (rohs 2 ) compliant. 2. see http://www.diodes.com/quality/lead_free.html for more information about diodes incorporateds definitions of hal ogen - and antimony - free, "green" and lead - f ree . 3. halogen - and antimony - free "green products are defined as those w hich contain <900ppm bromine, <900ppm chlorine (<1500ppm total br + cl) and <1000ppm antimony compounds. fb gnd vcc vin gnd sw sw boot pgood en pin 1 mark 1 2 3 4 5 6 7 8 9 10 11 ep
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 2 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated typical applications circuit note 4 : when using a single power supply for v cc and v in , a 4.7 ? resistor s hould be placed between them for noise isolation. component value unit component value unit c vcc 1 f c in 44 f r pg 10 k ? c boot 0.1 f r fb2 tbd k ? l1 1.5 h r fb1 tbd k ? c out 88 f table 1. component guide p g o o d e p e n v c c f b g n d g n d s w s w b o o t v i n r p g v c c c v c c v o u t c b o o t l 1 c o u t r f b 2 r f b 1 v i n c i n 9 1 0 2 1 6 7 4 5 1 1 8 3 a p 3 4 3 6 / a
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 3 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated pin description s pin number p in name fun ction 1 fb voltage feedback input. connect to v out through a voltage divider to set the output voltage 2 vcc analog power input 3 vin power input 4, 5 gnd ground. must be connected to gnd on pcb 6, 7 sw power switch output 8 boot high side switch dri ver supply 9 pgood open drain power good output 10 en enable 11 exposed pad thermal connection to the pcb. must be connected to gnd on pcb functional block diagram 7 5 % l o g i c 1 2 5 % e a v o l t a g e r e f e r e n c e s o f t s t a r t e n s h u t d o w n l o g i c t h e r m a l s h u t d o w n u v l o b o o t c h a r g e b o o t u v l o l o g i c a n d p w m l a t c h p w m s l o p e c o m p e n s a t i o n o s c i l l a t o r c u r r e n t l i m i t a n d s h o r t p r o t e c t i o n c u r r e n t s e n s e f b 1 2 v c c 9 1 0 p g o o d e n g n d g n d s w b o o t 3 v i n 8 6 , 7 4 , 5 4 , 5 +
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 4 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated absolute maximum ratings ( note 5 ) symbol pa rameter rating unit v cc, v in vcc, vin pin voltage - 0.3 to 6 v v en en pin voltage - 0.3 to 6 v v sw sw pin voltage - 0.3 to v in +0.3 v v sw_transient sw pin transient voltage ( <50n s) - 5 to v in +5 v v fb f b pin voltage - 0.3 to 6 v v pgd pgood pin voltage - 0.3 to 6 v v boot_sw boot to sw voltage 0 to 6 v ja thermal resistance (junction to ambient, simulation) 33 oc/w jc thermal resistance (junction to case ) 3 oc/w t j operating junction temperature - 40 to + 150 oc t stg storage temperature - 65 to + 150 oc t lead lead temperature (soldering, 10sec) + 260 oc v hbm esd (human body model) 2000 v v mm esd (machine model) 200 v note 5 : stresses greater than those listed under absolute maximum ratings may cause permanent damage to the device. these are stres s ratings only, and functional operation of the dev ice at these or any other conditions beyond those indicated under recommended operati ng conditions is not implied. exposure to absolute maximum ratings for extended periods may affect device reliability . recommended operating conditions symbol p arameter min max unit v cc analog input voltage 3.0 5.5 v v in power input voltage 1.3 5.5 v i out(max) maximum output current 3 C a v out output voltage 0.8 v in v t a operating ambient temperature - 40 + 85 oc
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 5 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated electrical characteristics ( v cc = 5v, v in = 5v, t a = + 25 c, unless otherwise specified . ) symbol parameter conditions min typ max unit supply voltage (vcc, vin pin) v cc analog power input voltage C 3.0 C 5.5 v v in power input voltage C 1.3 C 5.5 v i q quiescent current v fb = 1.5v, v cc = 5v , v in = 5v C 400 C a i shdn shutdown supply current v en = 0v, 3.0v v cc 5.5v, 1.3v v in 5.5v C C 1 a power on reset v uvlo internal under voltage lockout threshold for v cc C C 2.75 2.85 v v hys_vcc internal under voltage hysteresis for v cc C C 1 50 C mv voltage reference (fb pin) v fb voltage reference 3.0v v cc 5.5v 0.591 0.600 0.609 v internal pwm frequency f pwm frequency 3.0v v cc 5.5v 1.0 1.25 1.5 mhz mosfet spec r on_h high side switch on - resistance v boot_sw = 5.0v C 50 100 m ? v boot_sw = 3.0v C 70 140 m ? r on_l low side switch on - resistance v cc = 5.0v C 50 100 m ? v cc = 3.0v C 70 140 m ? current limit i limit current limit threshold C 4.8 7.6 C a thermal shutdown t tsd thermal shutdown C C + 160 C c C hysteresis C C + 20 C c boot spec (boot pin) r boot boot charge resistor v cc = 5.0v C 16 C ? C boot to sw uvlo v cc = 3.0v C 2.2 C v soft start t s s soft start time C 0.8 C 2 ms
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 6 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated electrical characteristics ( cont. v cc = 5v, v in = 5v, t a = + 25 c, unless otherwise specified . ) symbol parameter conditions min typ max unit enable (en pin) v en_l en pin threshold C C C 0.8 v v en_h C 1.6 C C v power good (pgood pin) v fbth feedback threshold v fb falling (fault) 70 75 C %v ref v fb rising (good) 77 82 C v fb rising (fault ) C 125 130 v fb falling (good) C 118 123 t pg_dly delay time for pgood from high to low C C 30 C s r pg internal power good pull low resistance C C C 150 ? r pg_up external pull - up resistance range C 3000 C C ? system performance v uvp output under voltage protection threshold v in = 1.3 to 5.5v C C 0.5 v out v t uvp delay time for uvp triggered v in = 1.5 to 5v C 65 C s v ovp output over voltage protection threshold v in = 1.3 to 5.5v 1.5 v out C C v t ovp delay time for ovp triggered v in = 1.5 to 5v C 65 C s i out output current v in = 1.5 to 5v, v out = 1.0v 3 C C a C output voltage line regulation v in = 1.5 to 5v, i out = 100ma C 0.4 C % v out /v C outpu t voltage load regulation i out = 0a to 3a C 0.3 C % v out /a v tran output voltage load transient v in = 5v, v out = 1.0v, di/dt = 400ma/ s C 2.5 C % v out /a efficiency v cc = 5v, v in =5v, i out = 3a, v out = 1.2v C 80 C %
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 7 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated performance characteristics efficiency vs. output current reference voltage vs. input voltage reference voltage vs. temperature pwm frequency vs. input voltage pwm frequency vs. temperature current limit vs. input voltage 3.00 3.25 3.50 3.75 4.00 4.25 4.50 4.75 5.00 5.25 5.50 0.590 0.592 0.594 0.596 0.598 0.600 0.602 0.604 0.606 0.608 0.610 input voltage(v) reference voltage(v) v in =v cc =v en 3.00 3.25 3.50 3.75 4.00 4.25 4.50 4.75 5.00 5.25 5.50 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 current limit (a) input voltage (v) v in =v cc =v en 3.00 3.25 3.50 3.75 4.00 4.25 4.50 4.75 5.00 5.25 5.50 1.00 1.05 1.10 1.15 1.20 1.25 1.30 1.35 1.40 1.45 1.50 pwm frequency (mhz) input voltage (v) v cc =v in =v en 0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00 0 10 20 30 40 50 60 70 80 90 100 output current (a) efficiency (%) v in =v cc =5.0v v out =1.0v AP3436 -40 -20 0 20 40 60 80 100 120 140 0.56 0.57 0.58 0.59 0.60 0.61 0.62 0.63 0.64 reference voltage(v) temperature ( o c) v in =v cc =5.0v -40 -20 0 20 40 60 80 100 120 140 1.00 1.05 1.10 1.15 1.20 1.25 1.30 1.35 1.40 1.45 1.50 pwm frequency (mhz) temperature ( o c) v in =v cc =5.0v
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 8 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated performance characteristics (con t.) current limit vs. temperature line regulation vs. input voltage load regulation vs. output current power on waveform (v in =v cc =5v, v out =1v, i out =3a) power off waveform enable wavefor m (v in =v cc =5v, v out =1v, i out =3a) (v in =v cc =5v, v out =1v, i out =3a) v in 2v/div v out 500mv/div i l 1a/div time 400 s/div time 1ms/div i l 1a/div v out 500mv/div v cc/in 2v/div v en 1v/div time 20ms/div v in 2v/div i l 2a/div v out 1v/div 0.00 0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00 -1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0 load regulation (%) output current (a) v in =v cc =v en =5.0v v out =1.0v 3.00 3.25 3.50 3.75 4.00 4.25 4.50 4.75 5.00 5.25 5.50 -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 line regulation (%) input voltage (v) v out = 1.0v v in = v cc = v en -40 -20 0 20 40 60 80 100 120 140 6.00 6.25 6.50 6.75 7.00 7.25 7.50 7.75 8.00 8.25 8.50 8.75 9.00 current limit (a) temperature ( o c) v in =v cc =5.0v
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 9 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated performance characteristics (cont.) disable waveform load transient response (v in =v cc =5v, v out =1v, i out =3a) (v in =v cc =5v, v out =1v, i out =0 to 3a) load transient response (v in =v cc =3.3v, v out =1v, i out =0 to 3a) time 200 s/div v cc/in 2v/div v en 1v/div v out 500mv/div i l 1a/div v out_ac 20mv/div i out 1a/div time 200 s/div time 200 s/div v out_ac 20mv/div i out 1a/div
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 10 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated application information 1. overview the AP3436/a is a 3a synchronous buck (step - down) converter with two integrated n - channel mosfets. for AP3436, the regulator operates in pwm mode with 1.25mhz switching frequency internally, regardless of if the load current is high or low. for AP3436a, when the load is very light, the regulator automatically operates in the psm mode to minimize the switching loss, thus achieving high efficiency at light load. when the load increases, the regulator automat ically switches over to a current - mode pwm operating at nominal 1.25mhz switching frequency. 2. power on reset a power on reset (por) circuitry continuously monitors the supply voltage at vcc pin. once the rising por threshold is exceed ed, the AP3436/a s ets itself to active state and is ready to accept chip enable command. the rising por threshold is typically 2.75v. 3. soft start a built - in soft - start is used to prevent surge current from power supply input v in during turn on (referring to the functiona l block diagram). the error amplifier is a three - input device. reference voltage v ref or the internal soft - start voltage v ss whichever is smaller dominates the behavior of the non - inverting inputs of the error amplifier. v ss internally ramps up to 0.6v aft er the soft - start cycle is initiated. the ramp is created digitally, so the output voltage will follow the v ss signal and ramps up smoothly to its target level. 4. en function the AP3436/a provides enable function. pulling this pin higher than 1.6v static ally enables the AP3436/a while pulling the pin lower than 0.8v statically for longer than 10 s will shutdown the ic. 5. adjusting output voltage the output voltage is set with a resistor divider from the fb pin. it is recommended to use divider resistor s with 1% tolerance or better. start with a 100k ? for the resistor r1 and use the following equation to calculate r2. consider using larger value resistors to improve efficien cy at very light loads. if the values are too high, the regulator is more suscept ible to noise and the voltage errors caused by fb input current are noticeable. figure 1 . voltage divider circuit 6 . short circuit protection (scp) the AP3436/a has over current protection (ocp) and under voltage protection (uvp) functions. 6.1 ocp function the high side switch current is detected during each cycle. during scp conditions, the output voltage is pulled down and the switch current is increased. once the increased high side switching current is detected to trigger the current l imit of high side switch, the high side switch will be immediately turned off and will not be turned on again until the next switching cycle. when over current condition is removed , the AP3436/a will recover back to normal operation again. 6.2 uvp functio n the fb voltage is also monitored for under voltage protection. the uv threshold is set at 0.2v. the under voltage protection has 65 s triggered delay. when uvp is triggered, both high side and low side are shutdown immediately. the uvp is a latched funct ion, reset power supply or en pin to restart AP3436/a again. 6 . 0 6 . 0 1 2 ? ? ? out v r r fb v out r 1 r 2 ap 3436 / a - + + 0 . 6 v v ss
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 11 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated application information (cont.) 7. over voltage protection (ovp) the output voltage is continuously monitored for over voltage protection by fb pin. when it is larger than 1.67 times as sett ing , the ovp function is triggered. the over voltage protection has 65 s triggered delay. when ovp is triggered, both high side and low side are shutdown immediately and the output voltage is discharged by an intern al 1k ? resistor. 8. power good the pgood pin output connects an open drain mosfet. the output is pulled low when the fb voltage enters the fault condition by falling below 75 % or rising above 12 5 % of the nominal internal reference voltage. there is a 7 % hyster esis on the threshold voltage, so when the fb voltage rises to the good condition above 82% or falls below 118% of the internal voltage reference the pgood output mosfet is turned off. it is recommended to use a pull - up resistor between the values of 3k ? a nd 100k ? to a voltage source that is 5v or less. 9. thermal shutdown the device implements an internal thermal shutdown to protect itself if the junction temperature exceeds + 160c. switching is stopped when the junction temperature exceeds the thermal trip threshold. once the die temperature decreases below + 140c, the device reinitiates the soft start operation. the thermal shutdown hysteresis is + 20c.
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 12 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated ordering information diodes ics pb - free products with "g1" suffix in the part number, are rohs compliant and green . package temperature range function part number marking id packing u - dfn 3 0 3 0 - 10 - 40 to +85 oc pwm AP3436dntr - g1 bdb 5000 / tape & reel pw m/psm AP3436adntr - g1 bdf 5000 / tape & reel mark ing information AP3436 (top view) AP3436a (top view) first l ine: logo and marking id second and third l ine s : date code y: y ear ww: w ork w eek of m olding m : a ssembly h ouse c ode xx: 7 th and 8 th d igits of batch no . first l ine: logo and marking id second and third l ine s : date code y: y ear ww: w ork w eek of m olding m : a ssembly h ouse c ode xx: 7 th and 8 th d igits of batch no . a p 3 4 3 6 x x x x x C p a c k i n g p a c k a g e t r : t a p e & r e e l a : a p 3 4 3 6 a b l a n k : a p 3 4 3 6 p r o d u c t n a m e p r o d u c t v e r s i o n d n : u - d f n 3 0 3 0 - 1 0 g 1 : g r e e n r o h s / g r e e n
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 13 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated package outline dimensions (all d imensions in mm ( inch ) . ) (1) package type: u - dfn 3 0 3 0 - 1 0 2 . 9 0 0 ( 0 . 1 1 4 ) 3 . 1 0 0 ( 0 . 1 2 2 ) 2 . 9 0 0 ( 0 . 1 1 4 ) 3 . 1 0 0 ( 0 . 1 2 2 ) 1 . 5 0 0 ( 0 . 0 5 9 ) 1 . 8 0 0 ( 0 . 0 7 1 ) 0 . 2 0 0 ( 0 . 0 0 8 ) 0 . 3 0 0 ( 0 . 0 1 2 ) 0 . 5 0 0 ( 0 . 0 2 0 ) t y p 0 . 2 5 0 ( 0 . 0 1 0 ) 0 . 5 5 0 ( 0 . 0 2 2 ) 0 . 0 0 0 ( 0 . 0 0 0 ) 0 . 0 5 0 ( 0 . 0 0 2 ) 2 . 3 0 0 ( 0 . 0 9 0 ) 2 . 5 0 0 ( 0 . 0 9 8 ) n 1 n 5 n 6 n 1 0 p i n 1 m a r k p i n # 1 i d e n t i f i c a t i o n s e e d e t a i l a 1 2 d e t a i l a 1 2 1 2 p i n 1 o p t i o n s s y m b o l a m i n ( m m ) m a x ( m m ) m i n ( i n c h ) m a x ( i n c h ) o p t i o n 1 o p t i o n 2 0 . 7 0 0 0 . 5 7 0 0 . 8 0 0 0 . 6 3 0 0 . 0 2 8 0 . 0 2 2 0 . 0 3 1 0 . 0 2 5 a 3 m i n ( m m ) m a x ( m m ) m i n ( i n c h ) m a x ( i n c h ) 0 . 1 5 3 0 . 1 5 0 ( t y p ) 0 . 2 5 3 0 . 0 0 6 0 . 0 0 6 ( t y p ) 0 . 0 1 0 a a 3
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 14 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated suggested pad layout (1) package t ype: u - dfn 3 0 3 0 - 1 0 dimensions y (mm)/(inch) x1 (mm)/(inch) y1 (mm)/(inch) x2 (mm)/(inch) y2 (mm)/(inch) e (mm)/(inch) value 3.300 /0.130 0.300/0.012 0.600/0.024 2.600/0.102 1.800/0.071 0.500/0.020 x 1 y 1 x 2 y 2 y e
ap 3 4 36/a document number: ds 37212 rev. 2 - 2 15 of 15 www.diodes.com april 2014 ? diodes incorporated ap34 36/a a pr oduct line of diodes incorporated important notice diodes incorporated makes no warranty of any kind, express or implied, with regards to this document, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose (and their equivalents under the laws of any jurisdiction). diodes incorporated and its subsidiaries reserve the right to make modifications, enhancements, improvements, corrections or other changes without further notice to this document and any product described herein. diodes incorporated does not assume any lia bility arising out of the application or use of this document or any product described herein; neither does diodes incorporated convey any license unde r its patent or trademark rights, nor the rights of others. any customer or user of this document or pro ducts described herein in such applications shall assume all risks of such use and will agree to hold diodes incorporated and all the companies whose products are represented on diod es incorporated website, harmless against all damages. diodes incorpora ted does not warrant or accept any liability whatsoever in respect of any products purchased through unauthorized sales chann el. should customers purchase or use diodes incorporated products for any unintended or unauthorized application, customers shall i ndemnify and hold diodes incorporated and its representatives harmless against all claims, damages, expenses, and attorney fees arising ou t of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized ap plication. products described herein may be covered by one or more united states, international or foreign patents pending. product nam es and markings noted herein may also be covered by one or more united states, international or foreign trademarks. th is document is written in english but may be translated into multiple languages for reference. only the english version of t his document is the final and determinative format released by diodes incorporated. life support diodes incorporated products are specifically not authorized for use as critical components in life support devices or systems without the express written approval of the chief executive officer of diodes incorporated. as used herein: a. life support devices or systems are devices or systems which: 1. are intended to implant into the body, or 2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided i n the labeling can be reasonably expected to result in signifi cant injury to the user. b. a critical component is any component in a life support device or system whose failure to perform can be reasonably expe cted to cause the failure of the life support device or to affect its safety or effectiveness. c ustomers represent that they have all necessary expertise in the safety and regulatory ramifications of their life support de vices or systems, and acknowledge and agree that they are solely responsible for all legal, regulatory and safety - related requireme nts concerning their products and any use of diodes incorporated products in such safety - critical, life support devices or systems, notwithstanding any devices - or systems - related information or support that may be provided by diodes incorporated. further , customers must fully indemnify diodes incorporated and its representatives against any damages arising out of the use of diodes incorporated products in such safety - critical, life support devices or systems. copyright ? 201 4 , diodes incorporated www.di odes.com

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