View UCC25705-Q1-15_9066271.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

ucc25705-q1 , ucc25706-q1 www.ti.com slusai1 C may 2011 high-speed voltage mode pulse width modulator check for samples: ucc25705-q1 , ucc25706-q1 1 features ? smallest footprint of the 8-pin msop package minimizes board area and height ? qualified for automotive applications ? greater than 4-mhz operation d package (top view) ? integrated oscillator / voltage feed forward compensation ? > 4:1 input voltage range ? 25-ns current limit delay ? programmable maximum duty cycle clamp ? optocoupler interface ? 50- a start-up current ? 4.2-ma operating current at 1 mhz ? latch-up exceeds 100ma per jesd78 class i description the ucc25705-q1 and ucc25706-q1 devices are 8-pin voltage mode primary side controllers with fast over-current protection. these devices are used as core high-speed building blocks in high performance isolated and non-isolated power converters. ucc25705-q1/ucc25706-q1 devices feature a high speed oscillator with integrated feed-forward compensation for improved converter performance. a typical current sense to output delay time of 25 ns provides fast response to overload conditions. the ic also provides an accurate programmable maximum duty cycle clamp for increased protection which can also be disabled for the oscillator to run at maximum possible duty cycle. two uvlo options are offered. the ucc25705-q1 with lower turn-on voltage is intended for dc-to-dc converters while the higher turn-on voltage and the wider uvlo range of the ucc25706-q1 is better suited for offline applications. the ucc2570x-q1 family is offered in an 8-pin soic (d) package. 1 please be aware that an important notice concerning availability, standard warranty, and use in critical applications of texas instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. production data information is current as of publication date. copyright ? 2011, texas instruments incorporated products conform to specifications per the terms of the texas instruments standard warranty. production processing does not necessarily include testing of all parameters. 12 3 4 87 6 5 ilim fb vff disch vdd out gnd rc
ucc25705-q1 , ucc25706-q1 slusai1 C may 2011 www.ti.com figure 1. typical application schematic absolute maximum ratings over operating free-air temperature (unless otherwise noted) (1) (2) value unit supply voltage 15 v input voltage (vff,rc,ilim) 7 v input voltage (fb) 15 v input current (disch) 1 ma output current (out) dc 20 ma storage temperature, t stg C 65 to 150 c junction temperature, t j C 55 to 150 c lead temperature (soldering, 10 sec) 300 c (1) stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. these are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. (2) all voltages are with respect to gnd. currents are positive into, negative out of the specified terminal. consult ti.com/packaging for more information. recommended operating conditions over operating free-air temperature range (unless otherwise noted) value unit t a operating ambient temperature C 40 to 105 c ordering information table top-side t a package orderable part number marking - C 40 c to 125 c soic-8 C d reel of 2500 ucc25706qdrq1 25706q - C 40 c to 125 c soic-8 C d reel of 2500 ucc25705qdrq1 preview 2 copyright ? 2011, texas instruments incorporated vdd out gnd rc ilim vff disch ucc2570x-q1 + -- v + out v in soft start circuit 4 5 3 6 8 7 1 tps2829 -- fb 2 mode =1 fet driver
ucc25705-q1 , ucc25706-q1 www.ti.com slusai1 C may 2011 esd ratings table parameter value unit human body model (hbm) 1000 v esd charged- device model (cdm) 1000 v machine model ( mm) 200 v copyright ? 2011, texas instruments incorporated 3
ucc25705-q1 , ucc25706-q1 slusai1 C may 2011 www.ti.com electrical characteristics v dd = 11 v, v in = 30 v, r t = 47 k, r disch = 400 k, r ff = 14 k, c t = 220 pf, c vdd = 0.1 f, and no load on the outputs, t a = - C 40 to 125 c, (unless otherwise specified) parameter test conditions min typ max unit uvlo section (uccx5705) start threshold 8.0 8.8 9.6 v stop threshold 7.4 8.2 9.0 v hysteresis 0.3 0.6 1.0 v uvlo section (uccx5706) start threshold 11.2 12.0 12.8 v stop threshold 7.2 8.0 8.8 v hysteresis 3.2 4.0 4.5 v supply current section start-up current v dd = uvlo start C 1 v, v dd comparator off 30 90 a i dd active v dd comparator on, oscillator running at 1 mhz 4.2 5.0 ma line sense section low line comparator threshold 0.95 1.00 1.15 v input bias current (vff) C 100 100 na oscillator section frequency vff = 1.2 v to 4.8 v 0.9 1.0 1.1 mhz vff = 1.2 v, see (1) 1.2 v ct peak voltage vff = 4.8 v, see (1) 4.8 v ct valley voltage see (1) 0 v current limit section input bias current 0.2 C 0.2 C 1 a current limit threshold 180 200 220 mv propagation delay, ilim to out 50 mv overdrive 25 35 ns pulse width modulator section fb input impedance v fb = 3 v 30 50 90 k minimum duty cycle v fb < 2 v 0 % v fb = v dd , f osc = 1 mhz 70 75 80 % maximum duty cycle v disch = 0 v, f osc = 1 mhz 93 % pwm gain v ff = 2.5 v, mode = 1 12 %/v propagation delay, pwm to out 65 130 ns output section v oh i out = C 5 ma, v dd C output 0.3 0.6 v v ol i out = 5 ma 0.15 0.4 v rise time c load = 50 pf 10 25 ns fall time c load = 50 pf 10 25 ns (1) specified by design. 4 copyright ? 2011, texas instruments incorporated
ucc25705-q1 , ucc25706-q1 www.ti.com slusai1 C may 2011 pin descriptions disch: a resistor to vin sets the oscillator discharge current programming a maximum duty cycle. when grounded, an internal comparator switches the oscillator to a quick discharge mode. a small 100-pf capacitor between disch and gnd may reduce oscillator jitter without impacting feed-forward performance. i disch must be between 25 a and 250 a over the entire v in range. fb: input to the pwm comparator. this pin is intended to interface with an optocoupler. input impedance is 50-k typical. gnd: ground return pin. i lim : provides a pulse-by-pulse current limit by terminating the pwm pulse when the input is above 200 mv. this provides a high speed (25 ns typical) path to reset the pwm latch, allowing for a pulse-by-pulse current limit. out: the output is intended to drive an external fet driver or other high impedance circuits, but is not intended to directly drive a power mosfet. this improves the controller s noise immunity. the output resistance of the pwm controller, typically 60 pull-up and 30 pull-down, will result in excessive rise and fall times if a power mosfet is directly driven at the speeds for which the ucc2570x-q1 is optimized. rc: the oscillator can be configured to provide a maximum duty cycle clamp. in this mode the on-time is set by rt and ct, while the off-time is set by r disch and ct.since the voltage ramp on ctis proportional to vin, feed-forward action is obtained. since the peak oscillator voltage is also proportional to vin, constant frequency operation is maintained over the full power supply input range. when thedisch pin is grounded, the duty cycle clamp is disabled. the rc pin then provides a low impedance path to ground ct during the off time. v dd : power supply pin. this pin should be bypassed with a 0.1- f capacitor for proper operation. the undervoltage lockout function of the ucc2570x-q1 allows for a low current startupmode and ensures that all circuits become active in a known state. the uvlo thresholds on the ucc25705-q1 are appropriate for a dc-to-dc converter application. the wider uvlo hysteresis of the ucc25706-q1 (typically 4 v) is optimized for a bootstrap startup mode from a high impedance source. v ff : the feed-forward pin provides the controllerwith a voltage proportional to the power supply input voltage. when the oscillator is providing a duty cycle clamp, a current of 2 i disch is sourced from the v ff pin. a single resistor r ff between v ff and gnd then set v ff to: when the disch pin is grounded and the duty cycle clamp is not used, the internal current source is disabled and a resistor divider from vin is used to set vff. in either case, when the voltage on v ff is less than 1.0 v, both the output and oscillator are disabled. copyright ? 2011, texas instruments incorporated 5 ff ff disch 2 r vff vin 2 r r ? ? ? ? + ?
ucc25705-q1 , ucc25706-q1 slusai1 C may 2011 www.ti.com figure 2. block diagram functional description oscillator and pwm the oscillator can be programmed to provide a duty cycle clamp or be configured to run at the maximum possible duty cycle. the pwm latch is set during the oscillator discharge and is reset by the pwm comparator when the c t waveform is greater than the feedback voltage. the voltage at the fb pin is attenuated before it is applied to the pwm comparator. the oscillator ramp is shifted by approximately 0.65-v at room temperature at the pwm comparator. the offset has a temperature coefficient of approximately - C 2 mv/ c. the i lim comparator adds a pulse by pulse current limit by resetting the pwm latch when v ilim > 200 mv. the pwm latch is also reset by a low line condition (v ff < 1.0 v). all reset conditions are dominant; asserting any output will force a zero duty cycle output. oscillator with duty cycle clamp (mode = 1) the timing capacitor c t is charged from ground to v ff through r t . the discharge path is through an on-chip current sink that has a value of 30 i disch , where i disch is the current through the external resistor r disch . since the charge and discharge currents are both proportional to v in , their ratio, and the maximum duty cycle remains constant as v in varies. 6 copyright ? 2011, texas instruments incorporated 7 2 5 8 out vdd 6 gnd s q q rd rd rd 1 ilim 200 mv current limit 1 pf 20 k 30 k + 0.7 v pwm s q q rd clk pwm latch 100 mv 2 * i (mode = 1) 0 (mode = 0) low line 1.0 v 30 *i(mode=1) 80 (mode =0) i rc vff fb 3 disch 4 50 mv vdd mode ucc25705-q1 (8.8v/8v) ucc25706-q1 (12v/8v) uvlo + -- + -- + -- + -- + -- + --
ucc25705-q1 , ucc25706-q1 www.ti.com slusai1 C may 2011 figure 3. duty cycle clamp (mode = 1) the on-time is approximately: the off-time is: the frequency is: the maximum duty cycle is: copyright ? 2011, texas instruments incorporated 7 ( ) t t disch off t disch c r r t 30 r -r = a 1 disch t t t disch 1 1 f r r c 30 r -r = a + on disch on off t t r duty cycle 1 t t 30 r ? ? = = - ? + ? 4 5 rc di sch 3 vff r ff 2 * i disch r disch r t c t v in 30 *i disch vdd i disch ff ff on t t in disch v 2 r t r c where v r = a a = ?
ucc25705-q1 , ucc25706-q1 slusai1 C may 2011 www.ti.com component selection for oscillator with duty cycle clamp (mode = 1) for a power converter with the following specifications: ? v in(min) = 18 v ? v in(max) = 75 v ? v in(shutdown) = 15 v ? f osc = 1 mhz ? max = 0.78 at v in(min) in this mode, the on-time is approximately: ? t on(max) = 780 ns ? t off(min) = 220 ns ? 1. pick c t = 220 pf. 2. calculate r t . r t = 51.1 k 3. r disch r disch = 383 k . i disch must be between 25 a and 250 a over the entire vin range. with the calculated values, i disch ranges from 44 a to 193 a, within the allowable range. if i disch is too high, c t must be decreased. 4. r ff the nearest 1% standard value to the calculated value is 13.7 k. 8 copyright ? 2011, texas instruments incorporated ff(min) 18 v = =1.20 v 15 in(min) on(max) t ff(min) t v t r v c = t disch ff(min) t t in(min) off(min) 30 r r v r c v 1 t = ? ? ? ? ? ? ? ? + ? ? ? ( ) ff(min) disch ff in(min) v r r 2 v 1 = -
ucc25705-q1 , ucc25706-q1 www.ti.com slusai1 C may 2011 oscillator without duty cyle clamp (mode = 0) in this mode, the timing capacitor is discharged through a low impedance directly to ground. the disch pin is externally grounded. a comparator connected to disch senses the ground connection and disables both the discharge current source and v ff current source. a resistor divider is now required to set v ff . figure 4. ocsillator without clamp (mode = 0) in this mode, the on-time is approximately: the off-time is: t off 75 ns the frequency is: copyright ? 2011, texas instruments incorporated 9 4 5 rc disch 3 vff r t c t v in ff on t t in v t r c where v = a a = t t 1 f r c 75ns = a +
ucc25705-q1 , ucc25706-q1 slusai1 C may 2011 www.ti.com component selection for oscillator without duty cycle clamp (mode = 0) for a power converter with the following specifications: ? v in(min) = 18 v ? v in(max) = 75 v ? v in(shutdown) = 15 v ? f osc = 1 mhz with these specifications, 1. pick c t = 220 pf 2. calculate r t . 10 copyright ? 2011, texas instruments incorporated ff(min) 18 v 1.2v 15 = = in(min) ff(min) osc t t v 1 75ns v f r c ? ? - ? ? =
ucc25705-q1 , ucc25706-q1 www.ti.com slusai1 C may 2011 typical characteristics ucc25705-q1 uvlo thresholds ucc25706-q1 uvlo thresholds vs vs temperature temperature figure 5. figure 6. operating current (at 1mhz) low-line threshold vs vs temperature temperature figure 7. figure 8. copyright ? 2011, texas instruments incorporated 11 -50 -25 0 25 5 0 7 5 100 125 temperature C 7 8 9 10 11 12 13 c uvlo -- thresholds -- v - 50 25 0 2 5 5 0 7 5 100 125 temperature C 8.0 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 8.9 c uvlo -- thresholds -- v - - 50 -25 0 25 5 0 7 5 100 125 temperature C 3.8 4.0 4.2 4.3 4.5 4.7 4.8 3.9 4.1 4.4 4.6 c i dd -- ma -50 -25 0 25 5 0 7 5 100 125 temperature 0.65 0.97 0.99 1.00 1.02 1.04 1.05 0.96 0.98 1.01 1.03 C c low-line threshold -- v
ucc25705-q1 , ucc25706-q1 slusai1 C may 2011 www.ti.com typical characteristics programmable maximum oscillator frequency duty cycle vs vs temperature temperature figure 9. figure 10. current-limit threshold current-limit prop delay vs vs temperature temperature figure 11. figure 12. 12 copyright ? 2011, texas instruments incorporated -50 -25 25 5 0 75 100 125 temperature C 0.90 1.00 1.10 0.95 1.05 oscillator frequency -- mhz c 0 - 50 -25 0 25 5 0 7 5 100 125 temperature 68 76 82 70 78 72 74 80 c programmable maximum duty cycle -- % -50 -25 0 25 5 0 7 5 100 125 temperature C 180 200 220 185 205 190 195 210 215 c current-limit threshold -- mv - 50 -25 0 25 5 0 7 5 100 125 temperature C 15 25 35 17 29 19 23 31 33 21 27 c current-limit propdelay -- ns
package option addendum www.ti.com 11-apr-2013 addendum-page 1 packaging information orderable device status (1) package type package drawing pins package qty eco plan (2) lead/ball finish msl peak temp (3) op temp (c) top-side markings (4) samples ucc25706qdrq1 active soic d 8 2500 green (rohs & no sb/br) cu nipdau level-1-260c-unlim -40 to 125 25706q (1) the marketing status values are defined as follows: active: product device recommended for new designs. lifebuy: ti has announced that the device will be discontinued, and a lifetime-buy period is in effect. nrnd: not recommended for new designs. device is in production to support existing customers, but ti does not recommend using this part in a new design. preview: device has been announced but is not in production. samples may or may not be available. obsolete: ti has discontinued the production of the device. (2) eco plan - the planned eco-friendly classification: pb-free (rohs), pb-free (rohs exempt), or green (rohs & no sb/br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. tbd: the pb-free/green conversion plan has not been defined. pb-free (rohs): ti's terms "lead-free" or "pb-free" mean semiconductor products that are compatible with the current rohs requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. where designed to be soldered at high temperatures, ti pb-free products are suitable for use in specified lead-free processes. pb-free (rohs exempt): this component has a rohs exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. the component is otherwise considered pb-free (rohs compatible) as defined above. green (rohs & no sb/br): ti defines "green" to mean pb-free (rohs compatible), and free of bromine (br) and antimony (sb) based flame retardants (br or sb do not exceed 0.1% by weight in homogeneous material) (3) msl, peak temp. -- the moisture sensitivity level rating according to the jedec industry standard classifications, and peak solder temperature. (4) multiple top-side markings will be inside parentheses. only one top-side marking contained in parentheses and separated by a "~" will appear on a device. if a line is indented then it is a continuation of the previous line and the two combined represent the entire top-side marking for that device. important information and disclaimer: the information provided on this page represents ti's knowledge and belief as of the date that it is provided. ti bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. efforts are underway to better integrate information from third parties. ti has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. ti and ti suppliers consider certain information to be proprietary, and thus cas numbers and other limited information may not be available for release. in no event shall ti's liability arising out of such information exceed the total purchase price of the ti part(s) at issue in this document sold by ti to customer on an annual basis. other qualified versions of ucc25706-q1 : ? catalog: ucc25706
package option addendum www.ti.com 11-apr-2013 addendum-page 2 note: qualified version definitions: ? catalog - ti's standard catalog product
tape and reel information *all dimensions are nominal device package type package drawing pins spq reel diameter (mm) reel width w1 (mm) a0 (mm) b0 (mm) k0 (mm) p1 (mm) w (mm) pin1 quadrant ucc25706qdrq1 soic d 8 2500 330.0 12.4 6.4 5.2 2.1 8.0 12.0 q1 package materials information www.ti.com 26-jan-2013 pack materials-page 1
*all dimensions are nominal device package type package drawing pins spq length (mm) width (mm) height (mm) ucc25706qdrq1 soic d 8 2500 367.0 367.0 35.0 package materials information www.ti.com 26-jan-2013 pack materials-page 2

important notice texas instruments incorporated and its subsidiaries (ti) reserve the right to make corrections, enhancements, improvements and other changes to its semiconductor products and services per jesd46, latest issue, and to discontinue any product or service per jesd48, latest issue. buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete. all semiconductor products (also referred to herein as ? components ? ) are sold subject to ti ? s terms and conditions of sale supplied at the time of order acknowledgment. ti warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in ti ? s terms and conditions of sale of semiconductor products. testing and other quality control techniques are used to the extent ti deems necessary to support this warranty. except where mandated by applicable law, testing of all parameters of each component is not necessarily performed. ti assumes no liability for applications assistance or the design of buyers ? products. buyers are responsible for their products and applications using ti components. to minimize the risks associated with buyers ? products and applications, buyers should provide adequate design and operating safeguards. ti does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or other intellectual property right relating to any combination, machine, or process in which ti components or services are used. information published by ti regarding third-party products or services does not constitute a license to use such products or services or a warranty or endorsement thereof. use of such information may require a license from a third party under the patents or other intellectual property of the third party, or a license from ti under the patents or other intellectual property of ti. reproduction of significant portions of ti information in ti data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties, conditions, limitations, and notices. ti is not responsible or liable for such altered documentation. information of third parties may be subject to additional restrictions. resale of ti components or services with statements different from or beyond the parameters stated by ti for that component or service voids all express and any implied warranties for the associated ti component or service and is an unfair and deceptive business practice. ti is not responsible or liable for any such statements. buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements concerning its products, and any use of ti components in its applications, notwithstanding any applications-related information or support that may be provided by ti. buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause harm and take appropriate remedial actions. buyer will fully indemnify ti and its representatives against any damages arising out of the use of any ti components in safety-critical applications. in some cases, ti components may be promoted specifically to facilitate safety-related applications. with such components, ti ? s goal is to help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and requirements. nonetheless, such components are subject to these terms. no ti components are authorized for use in fda class iii (or similar life-critical medical equipment) unless authorized officers of the parties have executed a special agreement specifically governing such use. only those ti components which ti has specifically designated as military grade or ? enhanced plastic ? are designed and intended for use in military/aerospace applications or environments. buyer acknowledges and agrees that any military or aerospace use of ti components which have not been so designated is solely at the buyer ' s risk, and that buyer is solely responsible for compliance with all legal and regulatory requirements in connection with such use. ti has specifically designated certain components as meeting iso/ts16949 requirements, mainly for automotive use. in any case of use of non-designated products, ti will not be responsible for any failure to meet iso/ts16949. products applications audio www.ti.com/audio automotive and transportation www.ti.com/automotive amplifiers amplifier.ti.com communications and telecom www.ti.com/communications data converters dataconverter.ti.com computers and peripherals www.ti.com/computers dlp ? products www.dlp.com consumer electronics www.ti.com/consumer-apps dsp dsp.ti.com energy and lighting www.ti.com/energy clocks and timers www.ti.com/clocks industrial www.ti.com/industrial interface interface.ti.com medical www.ti.com/medical logic logic.ti.com security www.ti.com/security power mgmt power.ti.com space, avionics and defense www.ti.com/space-avionics-defense microcontrollers microcontroller.ti.com video and imaging www.ti.com/video rfid www.ti-rfid.com omap applications processors www.ti.com/omap ti e2e community e2e.ti.com wireless connectivity www.ti.com/wirelessconnectivity mailing address: texas instruments, post office box 655303, dallas, texas 75265 copyright ? 2013, texas instruments incorporated

▲Up To Search▲

Price & Availability of UCC25705-Q1-15

	To Download UCC25705-Q1-15 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .