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document number: mc33998 rev. 2.0, 8/2006 freescale semiconductor technical data freescale semiconductor, inc. reserves the right to change the detai l specifications, as may be required, to permit improvements in the design of its products. ? freescale semiconductor, in c., 2007. all rights reserved. switching power supply with linear regulators the 33998 is a medium-power, multi-output power supply integrated circuit that is capabl e of operating over a wide input voltage range, from 6.0 v up to 26.5 v with 40 v transient capability. it incorporates a sensorless current mode control step-down switching controller regulating directly to 5.0 v. the 2.6 v linear regulator uses an external pass transistor to reduce the 33998 power dissipation. the 33998 also provides a 2.6 v linear standby regulator and two 5.0 v sensor supply outputs protected by internal low- resistance ldmos transistors. there are two separate enable pins for the main and sensor supply outputs and standard supervisory functions such as resets with power-up reset delay. the 33998 provides proper power supply sequencing for advanced microprocessor architec tures such as the mpc5xx and 683xx microprocessor families. features ? operating voltage range 6.0 v up to 26.5 v (40 v transient) ? step-down switching regulator output v ddh = 5.0 v @ 1400 ma (total) ? linear regulator with external pass transistor v ddl = 2.6 v @ 400 ma ? low-power standby linear regulator v kam = 2.6 v @ 10 ma ?two 5.0 v @ 200 ma (typical) sensor supplies v ref protected against short-to-battery and shor t-to-ground with retry capability ? undervoltage shutdown on the v ddl , v ddh outputs with retry capability ? reset signals ? power-up delay ? enable pins for main supplies (en) and sensor supplies (snsen) ? power sequencing for advanced microprocessor architectures ? pb-free packaging designated by suffix code eg figure 1. 33998 simplified application diagram switching regulator dw suffix eg suffix (pb-free) 98asb42344b 24-pin soicw 33998 ordering information device temperature range (t a ) package mc33998dw/r2 -40c to 125c 24 soicw mcz33998eg/r2 5.0 v 33998 5.0 v 5.0 v 2.6 v 2.6 v mcu snsen vref1 vpwr ka_vpwr gnd en vsw vddh drvl fbl pwrok vkam vkamok vref2 v ddh v kam v ddl
analog integrated circuit device data 2 freescale semiconductor 33998 internal block diagram internal block diagram figure 2. 33998 simplifi ed internal block diagram snse n vpwr ka_ vpwr pg nd 3 3 998 en vsw vddh drvl fbl pwrok v kam vka mo k v bg vref1 vref2 i-lim ramp osc sof t start lo gic & la tch pwro k vkamok por 2.6v linear regulator driver 2.6v standby reg. bandgap volta ge re fe re nce charge pump v ref1 re g. v ref2 re g. v bg v bg cres vsum fbkb en ab le co nt ro l enb sn sen b 5.0 v 5.0 v 2. 6 v 5.0 v 2. 6 v snsenb sn sen b en b en b enb retry retry drive
analog integrated circuit device data 3 freescale semiconductor 33998 pin connections pin connections figure 3. 33998 pin connections table 1. pin definitions pin number pin name definition 1 vkamok keep-alive output monitoring. this pin is an "open-drain" output that will be used with a discrete pull-up resistor to v kam . when the supply voltage to the 33998 is di sconnected or lost, the vkamok signal goes low. 2 ka_v pwr keep alive power supply pin. this s upply pin is used in modules that have both direct battery connections and ignition switch activated connections. 3 c res reservoir capacitor. this pin is tied to an external "reservoir capacitor" for the internal charge pump. 4 v pwr power supply pin. main power input to the ic. this pin is directly connected to the switching regulator power mosfet. in automotive applications this pin mu st be protected against reve rse battery conditions by an external diode. 5 ? 8 gnd ground of the integrated circuit. 9 v sw internal p-channel power mosfet drain. v sw is the "switching node" of the voltage buck converter. this pin is connected to the v pwr pin by an integrated p-channel mosfet. 10 pwrok power ok reset pin. this pin is an "open-drain" output that will be used with a discrete pull-up resistor to v kam , v ddh , or v ddl . when either v ddh or v ddl output voltage goes out of the regulation limits this pin is pulled down. 11 fbkb step-down switching regulator feedback pin. the fbkb pin is the v ddh feedback signal for the switching regulator. 12 v sum error amplifier "summing node". the v sum pin is connected to the inverti ng input of the error amplifier. this node is also the "common" point of the integrated feedback resistor divider. 13 drvl drive for v ddl (2.6 v) regulator. the drvl pin drives the base of an external npn pass transistor for the v ddl linear post regulator. the collector of t he vddl pass transistor is connected to v ddh . an example of a suitable pass transistor is bcp68. 14 fbl feedback for v ddl (2.6 v) regulator. the fbl pin is the voltage feedback sense signal from the v ddl (2.6 v) linear post regulator. 15 v ddh v ddh is an input supply pin providing power for the buffe red sensor supplies and the drive circuitry for the 2.6 v linear power regulator. the v ddh pin is supplied from the switching regulator output, capable of providing 5.0 v @ 1400 ma total output current. 16 v ref2 sensor supply #2 output. the v ref2 pin is sensor supply output #2. 17 ? 20 gnd ground of the integrated circuit. 21 v ref1 sensor supply #1 output. the v ref1 pin is sensor supply output #1. vkam gnd gnd gnd gnd vref2 vddh fbl drvl en snsen vref1 vkamok gnd gnd gnd gnd vsw pwrok vsum ka_vpwr cres vpwr fbkb 5 6 7 8 9 10 11 12 2 3 4 24 20 19 18 17 16 15 13 23 22 21 14 1
analog integrated circuit device data 4 freescale semiconductor 33998 pin connections 22 snsen sensor supply enable input. the snsen pin is an input, which enables the v ref1 and v ref2 supplies. it allows the control module hardware / software to shut down the sensor supplies. 23 en enable input. the en pin is an input, which enables t he main switching regulator and all other functions. when this pin is low, the power supply is in a low quiescent state. 24 v kam keep-alive (standby) 2.6 v regulator output. this is a 2.6 v low quiescent, low dropout regulator for keep alive memory. table 1. pin definitions (continued) pin number pin name definition
analog integrated circuit device data 5 freescale semiconductor 33998 electrical characteristics maximum ratings electrical characteristics maximum ratings table 2. maximum ratings all voltages are with respect to ground unless otherwise noted. rating symbol value unit main supply voltage v pwr -0.3 to 45 v keep-alive supply voltage ka_v pwr -0.3 to 45 v switching node v sw -0.5 to 45 v 5.0 v input power v ddh -0.3 to 6.0 v sensor supply v ref1 v ref2 -0.3 to 18 -0.3 to 18 v keep-alive supply voltage v kam -0.3 to 6.0 v maximum voltage at logic i/o pins en snsen pwrok vkamok -0.3 to 6.0 -0.3 to 6.0 -0.3 to 6.0 -0.3 to 6.0 v charge pump reservoir capacitor voltage c res -0.3 to 18 v error amplifier summing node v sum -0.3 to 6.0 v switching regulator output feedback fbkb -0.3 to 6.0 v vddl base drive drvl -0.3 to 6.0 v vddl feedback fbl -0.3 to 6.0 v esd voltage human body model (all pins) (1) machine model (all pins) (1) v esd1 v esd2 500 100 v power dissipation (t a = 25 c) (2) p d 800 mw thermal resistance, junction to ambient (3) , (4) r ja 60 c/w thermal resistance, junction to board (5) r jb 20 c/w operational package temperature [ambient temperature] (6) t a -40 to 125 c notes 1. esd1 testing is performed in accordance with the human body model (c zap = 100 pf, r zap = 1500 ? ). esd2 testing is performed in accordance with the machine model (c zap = 200 pf, r zap = 0 ? ) 2. maximum power dissipation at indicated junction temperature. 3. junction temperature is a function of on -chip power dissipation, package thermal re sistance, mounting site (board) temperatur e, ambient temperature, air flow, power dissipation of other components on the board, and board thermal resistance. 4. per semi g38-87 and jedec jesd51-2 wi th the single layer board horizontal. 5. thermal resistance between the die and the printed circuit boar d per jedec jesd51-8. board temperature is measured on the top surface of the board near the package. 6. the limiting factor is junction temperat ure, taking into account the power dissi pation, thermal resistance, and heat sinking.
analog integrated circuit device data 6 freescale semiconductor 33998 electrical characteristics maximum ratings operational junction temperature t j -40 to 150 c storage temperature t stg -55 to 150 c peak package reflow temperature during reflow (7) , (8) t pprt note 8 c 7. pin soldering temperature limit is for 10 seconds maximum duration. not designed for immersion soldering. exceeding these lim its may cause malfunction or permanent damage to the device. 8. freescale?s package reflow capability meets pb-free requir ements for jedec standard j-std-020c. for peak package reflow temperature and moisture sensitivity levels (msl), go to www.freescale.com, search by part number [e.g. remove prefixes/suffixes and enter the core id to view all orderable parts . (i.e. mc33xxxd enter 33xxx), and review parametrics. table 2. maximum ratings (continued) all voltages are with respect to ground unless otherwise noted. rating symbol value unit
analog integrated circuit device data 7 freescale semiconductor 33998 electrical characteristics static electrical characteristics static electrical characteristics table 3. static electrical characteristics characteristics noted under conditions 9.0 v v pwr 16 v, -40 c t j = t a 125 c, using the typical application circuit (see figure 8 ) unless otherwise noted. typical values noted reflect the approximate parameter mean at t a = 25 c under nominal conditions unless otherwise noted. characteristic symbol min typ max unit general supply voltage range normal operating voltage range (9) extended operating voltage range (9) v pwr(n) v pwr(e) 6.0 18 ? ? 18 26.5 v maximum transient voltage - load dump (10) v pwr(ld) ? ? 40 v vpwr supply current en = 5.0 v, v pwr = 14 v, no loads i vpwr 25 ? 150 ma vpwr quiescent supply current en = 0 v, v pwr = 12 v i qvpwr 5.0 ? 15 a ka_vpwr supply current, en = 5.0 v, ka_v pwr = 14 v, no load on v kam i kavpwr 0.5 ? 3.0 ma ka_vpwr quiescent supply current en = 0 v, ka_v pwr = 12 v i qkavpwr 50 ? 350 a buck regulator (vddh) buck converter output voltage i vddh = 200 ma to 1.4 a, v pwr = ka_v pwr = 14 v v ddh 4.9 ? 5.1 v buck converter output voltage i vddh = 1.4 a, v pwr = ka_v pwr = 6.0 v v ddh 4.9 ? 5.1 v vddh line regulation v pwr = ka_v pwr = 10 v to 14 v, i vddh = 200 ma regln vddh -20 ? 30 mv vddh load regulation v pwr = ka_v pwr = 14 v, i vddh = 200 ma to 1.4 a v pwr = ka_v pwr = 6.0 v, i vddh = 200 ma to 1.4 a regld vddh -20 -20 ? ? 20 20 mv vddh active discharge resistance v pwr = ka_v pwr = 14 v, en = 0 v, i vddh = 10 ma r hdisch 1.0 ? 15 ? p-channel mosfet drain-source breakdown voltage?not tested (11) bv dss 45 ? ? v drain-source current limit?not tested (11) isc sw1 ? -7.0 ? a notes 9. vddh is fully functional when the 33998 is operating at higher battery voltages, but these parameters are not tested. the tes t condition as are: a) v ddh must be between 4.9 v and 5.1 v (200 ma to 1.4 a) for v pwr = 14 v to 18 v. b) v ddh must be between 4.8 v and 5.5 v (200 ma to 1.4 a) for v pwr = 18 v to 26.5 v. 10. part can survive, but no parameters are guaranteed. 11. guaranteed by design but not production tested.
analog integrated circuit device data 8 freescale semiconductor 33998 electrical characteristics static electrical characteristics linear regulator (vddl) vddl output voltage v pwr = ka_v pwr = 14 v, i vddl = 200 ma v ddl 2.5 2.6 2.7 v vddl line regulation v ddh = 4.8 v to 5.2 v, i vddl = 400 ma regln vddl -30 ? 30 mv vddl load regulation v pwr = ka_v pwr = 14 v, i vddl = 10 ma to 400 ma regld vddl -70 ? 70 mv drvl output current v pwr = ka_v pwr = 14 v, vdrvl = 1.0 v i drvl 5.0 11 25 ma vddl active discharge resistance v pwr = ka_v pwr = 14 v, en = 0 v, i fbl = 10 ma r ldisch 1.0 ? 10 ? vddh to vddl active clamp resistance v pwr = ka_v pwr = 14 v, en = 0 v, i vddh = 50 ma, v fbkb = 0 v r clamp 0.6 ? 10 ? vddl output capacitor capacitance (12) c vddl ? 68 ? f vddl output capacitor esr (12) esr vddl ? 0.125 ? ? keep-alive (standby) regulator (vkam) vkam output voltage i vkam = 5.0 ma, vpwr = ka_v pwr = 18 v, en = 5.0 v v kam 2.5 ? 2.7 v vkam output voltage, en = 0 v (standby mode) v pwr = ka_v pwr = 26 v, i vkam = 0.5 ma v pwr = ka_v pwr = 18 v, i vkam = 5.0 ma v pwr = ka_v pwr = 5.0 v, i vkam = 10.0 ma v pwr = 0 v, ka_v pwr = 3.5 v, i vkam = 5.0 ma v kam 2.5 2.5 2.5 2.0 ? ? ? ? 2.7 2.7 2.7 2.7 v vkam line regulation, en = 0 v (standby mode) v pwr = ka_v pwr = 5.0 v to 18 v, i vkam = 2.0 ma regln vkam -20 ? 20 mv vkam load regulation, en = 0 v (standby mode) v pwr = ka_v pwr = 14 v, i vkam = 1.0 ma to 10 ma regldd vkam 0 ? 100 mv differential voltage v kam - v ddl en = 5.0 v, i vkam = 5.0 ma, v pwr = ka_v pwr = 14 v, i vddl = 200 ma reg vkam -20 ? 60 mv vkam output capacitor capacitance (12) c vkam ? 4.7 ? f vkam output capacitor esr (12) esr vkam ? 1.4 ? ? notes 12. recommended value. table 3. static electrical characteristics (continued) characteristics noted under conditions 9.0 v v pwr 16 v, -40 c t j = t a 125 c, using the typical application circuit (see figure 8 ) unless otherwise noted. typical values noted reflect the approximate parameter mean at t a = 25 c under nominal conditions unless otherwise noted. characteristic symbol min typ max unit
analog integrated circuit device data 9 freescale semiconductor 33998 electrical characteristics static electrical characteristics sensor supplies (vref1, vref2) vref on-resistance, t a = -40c i vref = 200 ma, i vddh = 200 ma, v pwr = ka_v pwr = 14 v, en = 5.0 v r ds(on) ? ? 280 m ? vref on-resistance, t a = +25c i vref = 200 ma, i vddh = 200 ma, v pwr = ka_v pwr = 14 v, en = 5.0 v r ds(on) ? ? 350 m ? vref on-resistance, t a = +125c i vref = 200 ma, i vddh = 200 ma, v pwr = ka_v pwr = 14 v, en = 5.0 v r ds(on) ? ? 455 m ? vref short-to-battery detect current v pwr = ka_v pwr = 14 v, en = 5.0 v, snsen = 5.0 v i sc_bat 500 ? 900 ma vref short-to-ground detect current v pwr = ka_v pwr = 14 v, en = 5.0 v, snsen = 5.0 v i sc_gnd 500 ? 900 ma maximum output capacitance (total) (13) c vref 33 ? 39 nf supervisory circuits (vpwr) pwrok undervoltage threshold on v ddl , fbl ramps down v pwr = ka_v pwr = 14 v, i vddh = 200 ma v fbl(thl) 2.1 2.4 2.5 v pwrok undervoltage threshold on v ddh v pwr = ka_v pwr = 14 v, i vddh = 200 ma v ddh(thl) 4.5 ? 4.8 v vddh overvoltage threshold v pwr = ka_v pwr = 10 v, i vddh = 200 ma v ddh(thh) 5.12 ? 5.7 v pwrok open drain on-resistance v pwr = ka_v pwr = 14 v, en = 5 v, i pwrok = 5.0 ma r ds(on) ? ? 200 ? vkamok threshold, v pwr = ka_v pwr = 14 v, i vddh = 200 ma v kam(thl) 2.1 2.4 2.5 v vkamok threshold on v pwr , v pwr ramps up ka_v pwr = 14 v, i vddh = 200 ma v pwrok(th) 4.0 ? 5.0 v vkamok open drain on-resistance v pwr = ka_v pwr = 14 v, en = 0 v, i vkamok = 10 ma r ds(on) 50 ? 200 ? enable input voltage threshold (pin en) v ih 1.0 ? 2.0 v enable pull-down current (pin en), en = 1.0 v v ddh to v il (min) i pd 500 ? 1200 na sensor enable input voltage threshold (pin snsen) v ih 1.0 ? 2.0 v sensor enable pull-down current (pin snsen) snsen = 1.0 v v ddh to v il (min) i pd 500 ? 1200 na notes 13. recommended value. table 3. static electrical characteristics (continued) characteristics noted under conditions 9.0 v v pwr 16 v, -40 c t j = t a 125 c, using the typical application circuit (see figure 8 ) unless otherwise noted. typical values noted reflect the approximate parameter mean at t a = 25 c under nominal conditions unless otherwise noted. characteristic symbol min typ max unit
analog integrated circuit device data 10 freescale semiconductor 33998 electrical characteristics static electrical characteristics charge pump (cres) charge pump voltage v pwr = ka_v pwr = 14 v, i vddh = 200 ma, i cp = 0 a v pwr = ka_v pwr = 14 v, i vddh = 200 ma, i cp = 10 a v cres 12 12 ? ? 15 15 v table 3. static electrical characteristics (continued) characteristics noted under conditions 9.0 v v pwr 16 v, -40 c t j = t a 125 c, using the typical application circuit (see figure 8 ) unless otherwise noted. typical values noted reflect the approximate parameter mean at t a = 25 c under nominal conditions unless otherwise noted. characteristic symbol min typ max unit
analog integrated circuit device data 11 freescale semiconductor 33998 electrical characteristics dynamic electrical characteristics dynamic electrical characteristics table 4. dynamic electr ical characteristics characteristics noted under conditions 9.0 v v pwr 16 v, -40 c t j = t a 125 c using the typical application circuit (see figure 8 ) unless otherwise noted. typical values noted reflect the approximate parameter mean at t a = 25 c under nominal conditions unless otherwise noted. characteristic symbol min typ max unit buck regulator (vddh) switching frequency (14) f sw ? 750 ? khz soft start duration (see figure 2 ) v pwr = ka_v pwr = 6.0 v t ss 5.0 ? 15 ms charge pump (cres) charge pump current ramp-up time v pwr = ka_v pwr = 14 v, c res = 22 nf, v cp = 1.0 v to 11 v t cres 1.0 ? 20 ms charge pump ramp-up time v pwr = ka_v pwr = 7.0 v, c res = 22 nf, v cp = 7.0 v to 10 v t cres 1.0 ? 10 ms sensor supplies (vref1, vref2) vref overcurrent detection time (see figure 3 ) v ref load r l = 5.0 ? to gnd, v ddh = 5.1 v, v pwr = ka_v pwr = 10 v, en = 5.0 v, snsen = 5.0 v t det 0.5 ? 2.0 s vref retry timer delay (see figure 3 ) v ref load r l = 5.0 ? to gnd, v ddh = 5.1 v, v pwr = ka_v pwr = 10 v, en = 5.0 v, snsen = 5.0 v t ret 5.0 ? 20 ms supervisory circuits (vpwr) pwrok delay time (power-on reset) (see figure 4 ) t d(pwrok) 5.0 ? 15 ms vkamok delay time (see figure 5 ) t d(vkamok) 10 ? 30 ms vddh power-up delay time (see figure 6 ) t d(vpwr) 1.0 ? 10 ms fault-off timer delay time (see figure 7 ) t fault 1.0 ? 10 ms notes 14. guaranteed by design but not production tested.
analog integrated circuit device data 12 freescale semiconductor 33998 electrical characteristics timing diagrams timing diagrams figure 4. soft-start time figure 5. vref retry timer figure 6. pwrok delay timer (power-on reset) 4.8v t ss 0 5.0 0 0 6.0 k a _ v p w r v d d h ( v ) e n ( v ) 5.0 v p w r ( v ) time ( v ) 2.5v vddh(v) en (v) vpwr (v) ka_vpwr (v) 0 5.0 0 0 14 k a _ v p w r v r e f ( v ) e n ( v ) 5.0 v p w r ( v ) 0 2.6 p w r o k ( v ) ??v time 2.0v t ret ??v s n s e n t det 4.8v 2.0v vref (v) en (v) vpwr (v) ka_vpwr (v) snsnen pwrok (v) 0 5.0 0 0 14 k a _ v p w r v d d h ( v ) e n ( v ) 5.0 v p w r ( v ) ( v ) t d(pwrok) 0 2.6 p w r o k ( v ) 4.6v time vddh (v) en (v) vpwr (v) ka_vpwr (v) pwrok (v)
analog integrated circuit device data 13 freescale semiconductor 33998 electrical characteristics timing diagrams figure 7. vkamok delay time figure 8. vddh power-up delay time figure 9. fault-off timer delay time t d(vkamok) 0 5.0 0 0 0 6.0 k a _ v p w r ( v ) v pw r =0v v k a m o k ( v ) v k a m ( v ) 2.6 e n ( v ) time 2.4v 2.6 vkam (v) en (v) ka_vpwr (v) vkam ok (v) 2.0v t d(vpwr) 0 5.0 0 0 0 18 k a _ v p w r v d d h ( v ) v p w r ( v ) 18 e n ( v ) 5.0 ( v ) time vpwr (v) en (v) ka_vpwr (v) vddh (v) 0 5.0 0 0 14 k a _ v p w r v d d h ( v ) e n ( v ) 5.0 v p w r ( v ) t fault 0 2.6 p w r o k ( v ) 4.7v 0 2.6 v d d l time 1.0v t fault 4.7v 1.0v ( v ) v d d h ( v ) e n ( v ) v p w r ( v ) k a _ v p w r ( v ) p w r o k ( v ) v d d h ( v )
analog integrated circuit device data 14 freescale semiconductor 33998 functional description introduction functional description introduction the 33998 multi-output power supply integrated circuit is capable of operating from 6.0 v up to 26.5 v with 40 v transient capability. it incorp orates a step-down switching controller regulating directly to 5.0 v. the 2.6 v linear regulator uses an external pass transistor, thus reducing the power dissipation of the integrated circuit. the 33998 also provides a 2.6 v linear standby regulator and two 5.0 v sensor supply outputs protect ed by internal low-resistance ldmos transistors against short-to-battery and short-to- ground. functional pin description switching regulator (vddh) the switching regulator is a high-frequency (750 khz), conventional buck converter with integrated high-side p- channel power mosfet. its output voltage is regulated to provide 5.0 v with 2% accuracy and it is intended to directly power the digital and analog circuits of the electronic control module (ecm). the switching regulator output is rated for 1400 ma total output current. this current can be used by the linear regulator vddl and sensor supplies vref1 and vref2. the 33998 switching controller utilizes "sensorless current mode control" to achieve good line rejection and stabilize the fee dback loop. a soft-start feature is incorporated into the 33998. when the device is enabled, the switching regulator output voltage vddh ramps up to about half of full scale and then takes 16 steps up to the nominal regulation voltage level (5.0 v nominal). 2.6 v linear regulator (vddl) the 2.6 v linear post-regulator is powered from the 5.0 v switching regulator output (vddh) . a discrete pass transistor is used to the power path for the vddl regulator. this arrangement minimizes the power dissipation off the controller ic. the fbl pin is the feedback input of the regulator control loop and the drvl pin the external npn pass transistor base drive. power up, power down, and fault management are coor dinated with the 5.0 v switching regulator. sensor supplies (vref1) and (vref2) the sensor supplies are im plemented using a protected switch to the main 5.0 v (switching regulator) output. the 33998 integrated circuit provid es two low-resistance ldmos power mosfets connected to the switching regulator output (vddh). these switches have short-to-battery and short-to- ground protection integrated into the ic. when a severe fault conditions is detected, the affe cted sensor output is turned off and the sensor retry timer starts to time out. after the retry timer expires, the sensor supply tries to power up again. sensor supplies vref can be disabled by pulling the sensor enable snsen pin low (see figure 7 for the vref retry timer operation). notes: severe fault conditions on the vref1 and vref2 outputs, like hard shorts to either ground or battery, may disrupt the operation of the main regulator vddh. shorts to battery above 17 v are considered ?double faults? and neither one of the vref outputs is protected against such conditions. depending on the vddh capacitor value and its esr value, the severity of the short may disrupt the vddh operation. keep-alive regulator, standby ( vkam) the keep-alive regulator vkam (keep-alive memory) is intended to provide power for ?key off? functions such as nonvolatile sram, ?keyoff" timers and controls, keyswitch monitor circuits, and perhaps a can/scp monitor and wake- up function. it may also power other low-current circuits required during a ?keyoff? conditi on. the regulated voltage is nominally 2.6 v. a severe fault condition on the vkam output is signaled by pulling the vkamok signal low. keep-alive operation, standby, power- down mode (vkam) when the en pin is pulled low, the power supply is forced into a low-current standby mode. in order to reduce current drawn by the vpwr and ka_vpwr pins, all power supply functions are disabled except for the vkam and enable (en) pins. the latter pin is monitored for the "wake-up" signal. the switching transistor gate is actively disabled and the vddl and vddh pins are actively pulled low. power-up delay timers two power-up delay timers are integrated into the control section of the integrated circui t. one timer monitors the input voltage at the v pwr input pin (see figure 3 ), and the other monitors the input voltage at the ka_v pwr input pin . in both cases, sufficient supply voltage must be present long enough for the timers to ?time out? before the switching regulator can be enabled. fault-off timer if the v ddl output voltage does not reach its valid range at the end of soft-start period, or if the v ddh or v ddl output voltage gets below its pwrok th reshold level, the fault-off timer shuts the switching regulat or off until the timer ?times out? and the switching regulat or retries to power up again (see figure 7 for fault-off timer operation details).
analog integrated circuit device data 15 freescale semiconductor 33998 functional description functional pin description power-on reset timer this timer starts to time ou t at the end of the soft-start period if the v ddh and v ddl outputs are in the valid regulation range. if the timer ?times out?, then the open-drain pwrok signal is released, indicating that ?power is on?. supervisory circuits (pwrok) and (vkamok) the 33998 has two voltage monitoring open-drain outputs, the pwrok and the vkamok pins. pwrok is "active high". this output is pulled low when ei ther of the regulator outputs (v ddh or v ddl ) are below their regulation windows. if both regulator outputs are above their respective lower thresholds, and the power-on reset timer has expired, the output driver is turned off and this pin is at high-impedance state (see figure 6 ). the vkamok signal indicates a severe fault condition on the keep-alive regulator output v kam . the v kam output voltage is compared to the internal bandgap reference voltage. when the v kam falls below the bandgap reference voltage level, the vkamok signal is pulled low.
analog integrated circuit device data 16 freescale semiconductor 33998 typical applications functional pin description typical applications figure 10. 33998 application circuit schematic diagram note the vddh total output current is 1.4 a. this includes the cu rrent used by the linear regulator vddl and buffered outputs vref1 and vref2. snse n vpwr ka_ vpwr gnd 33998 en vsw vddh drvl fbl pwrok v kam vka mo k v bg vref1 vref2 i-lim ramp osc sof t st art lo gic & la tch pwrok vka mo k por 2.6v linear regulator driver 2.6v st and by reg. bandgap volta ge re fe re nce charge pump v ref1 re g. v ref2 re g. v bg v bg cres vsum fbkb enable control enb sn sen b snsenb sn sen b en b en b enb retry retry drive c9 22nf cs1 33nf lf1 10uh c2 1.0 uf 10 0u f c1 cf2 1. 0u f 10uf cf1 cs2 33nf c6 68 uf 10 0n f c5 c4 100nf 68 uf c3 l1 15uh c7 4.7uf r1 10 k r2 10k q1 rc1 3.6k cc 1 2.2nf d1 dp1 dp2 9 11 12 15 13 14 24 1 10 5-8 17-20 22 23 3 16 21 2 4 v ddl =2.6v @400ma v kam =2.6v @10ma v ddh =5.0v @ 1400ma total c8 390pf r3 2.2r optional snubber
analog integrated circuit device data 17 freescale semiconductor 33998 typical applications functional pin description table 5. recommended components designator value / rating description / part no. manufacturer (16) cf1 10 f / 50 v aluminum electrolytic / uub1h100mnr nichicon cf2, c2 1.0 f / 50 v ceramic x7r / c1812c105k5ractr kemet c1 100 f / 50 v aluminum electrolytic / uuh1v101mnr nichicon c3 (15) 68 f / 10 v tantalum / t494d686m010as kemet c6 68 f / 10 v tantalum / t494d686m010as kemet c7 4.7 f / 10 v tantalum / t494a475m010as kemet c4, c5 100 nf / 16 v ceramic x7r any manufacturer c8 (optional) 390 pf / 50 v ceramic x7r any manufacturer c9 22 nf / 25 v ceramic x7r any manufacturer cs1, cs2 33 nf / 25 v ceramic x7r any manufacturer cc1 2.2 nf / 16 v ceramic x7r any manufacturer r1, r2 10 k ? resistor 0805, 5% any manufacturer r3 (optional) 2.2 ? resistor 0805, 5% any manufacturer rc1 3.6 k ? resistor 0805, 5% any manufacturer lf1 10 h cdrh127-100m or slf10145-100m2r5 sumida tdk l1 15 h cdrh127-150mc or slf10145-150m2r2 sumida tdk q1 1.0 a / 20 v bipolar transistor / bcp68t1 on semiconductor d1 2.0 a / 50 v schottky diode / ss25 general semiconductor dp1 3.0 a / 200 v diode / murs320 on semiconductor dp2 27 v transient voltage suppressor / sm5a27 general semiconductor notes 15. it is possible to use ceramic capacitors in the switcher output, e.g. c3 = 2 x 22 f / 6.3 v x7r ceramic. in this case the compensation resistor has to be changed to rc1 = 200 ? to stabilize the switching regulator operation. 16. freescale semiconductor does not assume liability, endorse, or wa rrant components from external manufacturers that are refer enced in circuit drawings or tables. while freescale semiconductor offers component recommendations in this configuration, it is the cus tomer?s responsibility to validate their application. 17. freescale semiconductor does not assume liability, endorse, or wa rrant components from external manufacturers that are refer enced in circuit drawings or tables. while freescale semiconductor offers component recommendations in this configuration, it is the cus tomer?s responsibility to validate their application.
analog integrated circuit device data 18 freescale semiconductor 33998 packaging package dimensions packaging package dimensions for the most current package revision, visit www.freescale.com and perform a keyword search using the ?98a? listed below. dwb suffix eg suffix (pb-free) 24 pin soic wide body plastic package 98asb42344b issue f
analog integrated circuit device data freescale semiconductor 19 33998 revision history revision history revision date description of changes 2.0 8/2006 ? implemented revision history page ? converted to freescale format ? update to the prevailing form and style ? removed mc33998eg/r2, and replaced with mcz339 98eg/r2 in the ordering information block ? removed peak package reflow temperature during reflow (solder reflow) parameter from maximum ratings on page 5 . added note with instructions from www.freescale.com.
mc33998 rev. 2.0 8/2006 information in this document is provided solely to enable system and software implementers to use freescale semiconduc tor products. there are no express or implied copyright licenses granted hereunder to design or fabricate any integrated circuits or integrated circuits based on the information in this document. freescale semiconductor reserves the right to make changes without further notice to any products herein. freescale semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does freescale semiconductor assume any liability ar ising out of the application or use of any product or circuit, and specifically discl aims any and all liability, including without limitation consequential or incidental damages. ?typical? parameters that may be provided in freescale semiconductor data s heets and/or specifications can and do vary in different applications and actual performance may vary over time. all operating parameters, including ?typicals?, must be validated for each customer application by customer?s technical experts. freescale se miconductor does not convey any license under its patent rights nor the rights of others. freescale semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the fa ilure of the freescale semiconductor product could create a situation where personal injury or death may occur. should buyer purchase or use freescale semiconductor products for any such unintended or unauthorized application, buyer shall indemni fy and hold freescale semiconductor and its officers, employees, subsidiaries, affili ates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that freescale semiconductor was negligent regarding the design or manufacture of the part. freescale? and the freescale logo are trademarks of freescale semiconductor, inc. all other product or service names are the property of their respective owners. ? freescale semiconductor, inc., 2007. all rights reserved. how to reach us: home page: www.freescale.com e-mail: support@freescale.com usa/europe or locations not listed: freescale semiconductor technical information center, ch370 1300 n. alma school road chandler, arizona 85224 +1-800-521-6274 or +1-480-768-2130 support@freescale.com europe, middle east, and africa: freescale halbleiter deutschland gmbh technical information center schatzbogen 7 81829 muenchen, germany +44 1296 380 456 (english) +46 8 52200080 (english) +49 89 92103 559 (german) +33 1 69 35 48 48 (french) support@freescale.com japan: freescale semiconductor japan ltd. headquarters arco tower 15f 1-8-1, shimo-meguro, meguro-ku, tokyo 153-0064 japan 0120 191014 or +81 3 5437 9125 support.japan@freescale.com asia/pacific: freescale semiconductor hong kong ltd. technical information center 2 dai king street tai po industrial estate tai po, n.t., hong kong +800 2666 8080 support.asia@freescale.com for literature requests only: freescale semiconductor literature distribution center p.o. box 5405 denver, colorado 80217 1-800-441-2447 or 303-675-2140 fax: 303-675-2150 ldcforfreescalesemiconductor@hibbertgroup.com rohs-compliant and/or pb-free versions of freescale products have the functionality and electrical characteristics of thei r non-rohs-compliant and/or non-pb-free counterparts. for further information, see http://www.freescale.com or contact your freescale sales representative. for information on freescale?s environmental products program, go to http:// www.freescale.com/epp .

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