technical data july 2009, ver.01 pwm control circuit the il494 incorporates on a single monolithic chip all the functions required in the construction of a pulse-width-modul ation control circuit. designed primarily for power supply control, the il 494 contains an on-chip 5- volt regulator, two error amplifiers, adjustable os cillator, dead-time control comparator, pulse-steering flip-flop, and output-co ntrol circuitry. the uncommitted output transistors provide either commo n-emitter or emitter- follower output capability. push-pull or single-end ed output operation may be selected through the output-control function. the a rchitecture of the il494 prohibits the possibility of either output being pu lsed twice during push-pull operation. feature complete pwm power control circuitry uncommitted outputs for 200 ma sink or source output control selects single-ended or push-pull op eration internal circuitry prohibits double pulse at either output internal regulator provides a stable 5 v reference supply variable dead-time provides control over total rang e il494a pin assignment function table output control output function grounded single-ended or parallel output at v ref normal push-pull operation logic diagram ordering information device operating temperature range package shipping il494an plastic dip-16 tube il494ad sop-16 tube IL494ADT t a = -20 to 85 c for all packages sop-16 tape& reel
il494a july 2009, ver.01 maximum ratings symbol parameter value unit v cc supply voltage 41 v v i amplifier input voltage v cc +0.3 v v o collector output voltage 41 v collector output current 250 ma tstg storage temperature -65 to +150 c recommended operating conditions symbol parameter min max unit v cc supply voltage 7 40 v v i amplifier input voltage -0.3 v cc - 2 v v o collector output voltage 40 v collector output current (each transistor) 200 ma current into feed back terminal 0.3 ma c t timing capacitor 0.47 10.000 nf r t timing resistor 1.8 500 k w oscillator frequency 1 300 khz t a operating free-air temperature -20 +85 c
il494a july 2009, ver.01 electrical characteristics (temperature -20 ~ 85 c, v cc = 15 v, f=10 khz)) symbol parameter test conditions min max unit reference section v ref output voltage i o =1 ma 4.95 5.05 v v regin output regulation v cc =7 v to 40 v, t a =25 c 25 mv v regout input regulation i o =1 to 10 ma, t a =25 c 15 mv d v ref output voltage change with temperature t a = -20 c to 85 c 1 % i sc short-circuit output current (note 1) vref=0 50 ma oscillator section f osc frequency c t =0.01 m f, r t =12 k w 6 14 khz d f osc standard deviation of frequency (note 2) all values of v cc , c t , r t , t a constant 15 % d f osc( d v) frequency change with voltage v cc = 7 v to 40 v, t a =25 c 10 % d f osc( d t) frequency change with temperature c t =0.01 m f, r t =12 k w t a = -20 c to 85 c 2 % dead time control section i ib(2t) input bias current (pin 4) v i = 0 to 5.25 v -10 m a dc max maximum duty cycle, each output v i(pin 4) =0 v 45 % v thd input threshold voltage zero duty cycle 3.3 v (pin 4) maximum duty cycle 0 error amp section v io input offset voltage v o(pin 3) =2.5 v 10 mv i io input offset current v o(pin 3) =2.5 v 250 na i ib input bias current v o(pin 3) =2.5 v 1 m a common-mode input v cc = 7 v to 40 v low -0.3 v voltage range high v cc - 2 a vol open-loop voltage amplification d v o =3 v, v o =0.5 to 3.5 v 70 db f b unity-gain bandwidth 100 khz cmrr common-mode rejection ratio v cc =40 v, t a =25 c 65 db i o output sink current (pin 3) v id =-15 mv to -5 v, v o(pin 3) =0.7 v 0.3 ma i o+ output source current (pin 3) v id =15 mv to 5 v, v o(pin 3) =3.5 v -2 ma
il494a july 2009, ver.01 electrical characteristics (temperature -20 ~ 85 c, v cc = 15 v, f=10 khz)) symbol parameter test conditions min max unit pwm comparator section v thp input threshold voltage (pin 3) zero duty cycle 4.5 v i i input sink current (pin 3) v o(pin 3) =0.7 v 0.3 ma switching characteristics t rc output voltage rise time common-emitter configurat ion 200 ns t fc output voltage fall time common-emitter configurat ion 100 ns t rf output voltage rise time emitter-follower configur ation 200 ns t ff output voltage fall time emitter-follower configur ation 100 ns output section i c(off) collector off-state current v ce =40 v, v cc =40 v 100 m a i e(off) emitter off-state current v cc =v c =40 v, v e =0 -100 m a v sat collector- emitter common- emitter v e =0, i c =200 ma 1.3 v saturation voltage emitter- follower v c =15 v, i e =-200 ma 2.5 i och output control input current v i =v ref 3.5 ma total device i cc standby supply current all other inputs & v cc =15 v 10 ma outputs open v cc =40 v 15 i cca average supply current v (pin 4) =2 v 17 ma notes: 1. duration of the short circuit should not exceed one second. 2. standard deviation is a measure of the statistic al disribution about the mean as derived from the f ormula n (x n - x) 2 n=1 s = n C 1
il494a july 2009, ver.01 typical application pulse width modulated step-down converter
il494a july 2009, ver.01 parameter measurement information 1. dead time and feedback control 2. error amplifier characteristics 3. common-emitter configuration 4. emitter-follower configuration
il494a july 2009, ver.01 typical performance curves figure 1 C oscillator frequency vs. timing resistance figure 2 C open loop voltage gain and phase vs. frequency figure 3 C percent dead time vs.oscillator frequency figure 4 C percent duty cycle vs. dead-time control voltage
il494a july 2009, ver.01 figure 5 C emitter-follower configuration output-saturation voltage vs. emitter current figure 6 C common-emitter configuration output-saturation voltage vs. collector current fugure 7 C standby-supply current vs. supply voltage
il494a july 2009, ver.01 n suffix plastic dip (ms - 001bb) symbol min max a 18.67 19.69 b 6.1 7.11 c 5.33 d 0.36 0.56 f 1.14 1.78 gh j 0 10 k 2.92 3.81 notes: l 7.62 8.26 1. dimensions a, b do not include mold flash or pr otrusions. m 0.2 0.36 maximum mold flash or protrusions 0.25 mm (0.010 ) per side. n 0.38 d suffix soic (ms - 012ac) symbol min max a 9.8 10 b 3.8 4 c 1.35 1.75 d 0.33 0.51 f 0.4 1.27 gh j 0 8 notes: k 0.1 0.25 1. dimensions a and b do not include mold flash or pro trusion. m 0.19 0.25 2. maximum mold flash or protrusion 0.15 mm (0.006) pe r side p 5.8 6.2 for a; for b ? 0.25 mm (0.010) per side. r 0.25 0.5 5.72 2.54 7.62 1.27 dimension, mm dimension, mm a b h c k c m j f m p g d r x 45 seating plane 0.25 (0.010) m t -t- 1 16 8 9 l h m j a b f g d seating plane n k 0.25 (0.010) m t -t- c 1 16 8 9
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