1/10 operational amplifiers n low supply current : 200 m a/amp. n medium speed : 2.1mhz n low level output voltage close to v cc - : 0.1v typ. n input common mode voltage range includes ground comparators n low supply current : 200 m a/amp. n (v cc = 5v) n input common mode voltage range includes ground n low output saturation voltage : 250mv (io = 4ma) reference n adjustable output voltage : n v ref to 36v n sink current capability : 1 to 100ma n 1% and 0.4% voltage precision n lacth-up immunity description the tsm102 is a monolithic ic that includes two op-amps, two comparators and a precision volt- age reference. this device is offering space and cost saving in many applications like power supply management or data acquisition systems. order code n = dual in line package (dip) d = small outline package (so) - also available in tape & reel (dt) pin connections (top view) part number temperature range package nd tsm102i -40c, +85c tsm102ai -40c, +85c n dip16 (plastic package) d so16 (plastic micropackage) 1 2 3 4 13 14 15 16 5 6 7 8 12 11 10 9 output 1 inverting input 1 non-inverting input 1 v cc + non-inverting input 2 inverting input 2 output 2 vref output 4 inverting input non-inverting input 4 non-inverting input 3 inverting input 3 output 3 cathode v cc - comp comp tsm102/a voltage and current controller june 2001
tsm102/a 2/10 absolute maximum ratings electrical characteristics v cc + = 5v, v cc - = 0v, t amb = 25c (unless otherwise specified) operational amplifier v cc + = 5v, v cc = gnd, r1 connected to v cc/2 , t amb = 25c (unless otherwise specified) symbol parameter value unit v cc dc supply voltage 36 v v id differential input voltage 36 v v i input voltage -0.3 to +36 v t oper operating free-air temperature range -40 to +125 c t j maximum junction temperature 150 c thermal resistante junction to ambient 150 c/w symbol parameter min. typ max. unit i cc total supply current t min. t amb t max 0.8 1.5 2 ma symbol parameter min. typ. max. unit v io input offset voltage t min t amb t max 14.5 6.5 mv dv io input offset voltage drift 10 m v/c i ib input bias current t min t amb t max 20 100 200 na i io input offset current t min t amb t max 520 40 na a vd large signal voltage gain r1=10k , v cc + = 30v, v o = 5v to 25v t min t amb t max 50 25 100 v/mv svr supply voltage rejection ratio v cc = 5v to 30v 80 100 db v icm input common mode rejection ratio t min t amb t max (v cc - ) to (v cc + ) -1.8 (v cc - ) to (v cc + ) -2.2 v cmr common mode rejection ratio v cc + = 30v, vicm = 0v to (v cc + ) -1.8 70 90 db i sc output short circuit current v id = 1v, v o = 2.5v source sink 3 3 6 6 ma v oh high level output voltage r l = 10k w v cc + = 30v t min t amb t max 27 26 28 v v ol low level output voltage r l = 10k w t min t amb t max 100 150 210 mv sr slew rate v cc = 15v v i = 10v, r l = 10k w , c l = 100pf 1.6 2 v/ m s gbp gain bandwidth product r l = 10k w , c l = 100pf, f = 100khz 1.4 2.1 mhz
tsm102/a 3/10 comparators v cc + = 5v, v cc = ground, t amb = 25c (unless otherwise specified) voltage reference electrical characteristics t amb = 25c (unless otherwise specified) ? m phase margin r l = 10k w , c l = 100pf 45 degrees thd toatal harmonic distortion 0.05 % e n equivalent input noise voltage f = 1khz 29 symbol parameter min. typ max. unit v io input offset voltage t min t amb t max 5 9 mv i io input offset current t min t amb t max 50 150 na i ib input bias current t min t amb t max 250 400 na i oh high level output current v id = 1v, v cc = v o = 30v t min t amb t max 0.1 1 na m a v ol low level output voltage v id = -1v, i sink = 4ma t min t amb t max 250 400 700 mv a vd large signal voltage gain r1 = 15k, v cc = 15v, v o = 1 to 11v 200 v/mv i sink output sink current v id = -1v, v o = 1.5v 616 ma v icm input common mode voltage range t min t amb t max 0 0 v cc + -1.5 v cc + -2 v v id differential input voltage v cc + v t re response time 1) r1 = 5.1k to v cc + ,v ref = 1.4v 1. the response time specified is for 100mv input step with 5mv overdrive. for larger overdrive signals, 300ns can be obtained. 1.3 m s t rel large signal response time v ref = 1.4v, vi = ttl, r1 = 5.1k to v cc + 300 ns symbol parameter value unit v ka cathode to anode voltage v ref to 36 v i k cathode current 1 to 100 ma symbol parameter min. typ max. unit v ref reference input voltage -(figure1)- t amb = 25c tsm102, v ka = v ref , i k = 10ma tsm102a, v ka = v ref , i k = 10ma 2.475 2.490 2.500 2.500 2.525 2.510 v d v ref reference input voltage deviation over temperature range -(figure1, note 1) ) v ka = v ref , i k = 10ma, t min t amb t max 730 mv symbol parameter min. typ. max. unit nv hz ----------- -
tsm102/a 4/10 temperature coefficient of reference input voltage - note 2) v ka = v ref , i k = 10ma, t min t amb t max 22 100 ppm/c ratio of change in reference input voltage to change in cath- ode to anode voltage -(figure2) i k = 10ma, d v ka = 36 to 3v -1.1 -2 mv/v iref reference input current -(figure2) i k = 10ma, r1 = 10k w , r2 = t amb = 25c t min t amb t max 1.5 2.5 3 m a d iref reference input current deviation over temperature range -(figure2) i k = 10ma, r1 = 10k w , r2 = t min t amb t max 0.5 1 m a i min minimum cathode current for regulation -(figure1) v ka = v ref 0.5 1 ma ioff off-state cathode current -(figure3) 180 500 na 1. d v ref is defined as the difference between the maximum and minimum values obtained over the full temperature range. d v ref = vref max. - vref min 2. the temperature coefficient is defined as the slopes (positive and negative) of the voltage vs temperature limits whithin which the reference voltage is guaranteed. symbol parameter min. typ max. unit v ref d t d --------------- v ref d v ka d --------------- - t1 t2 temperature v ref max. v ref min. 25c temperature max 2.5v min - n ppm / c + n ppm / c
tsm102/a 5/10 figure 1 : test circuit for v ka = v ref figure 2 : test circuit for v ka > v ref figure 3 : test circuit for i off v k a v ref input i k v ka i k v ref i ref r r input 1 2 v ka v ref 1 r1 r2 ------- - + ? ?? i ref r1 C + = v ka input i off = 36v
6/10 this application note explains how to use the tsm102 in an smps-type battery charger which features : n voltage control n current control n low battery detection and end of charge detection 1 - tsm102 pr esentation the tsm102 integrated circuit includes two oper- ational amplifiers, two comparators and one ad- justable precision voltage reference (2.5v to 36v, 0.4% or 1%). tsm102 can sustain up to 36v power supply volt- age. figure 1: tsm102 pinout 2 - application context and principle of operation in the battery charging field which requires ever in- creasing performances in more and more reduced space, the tsm102a provides an attractive solu- tion in terms of pcb area saving, precision and versatility. figure 2 shows the secondary side of a battery charger (smps type) where tsm102a is used in optimised conditions : the two operational amplifi- ers perform current and voltage control, the two comparators provide end of charge and low battery signals and the voltage reference en- sures precise reference for all measurements. the tsm102a is supplied by an auxiliary power supply (forward configuration - d7) regulated by a bipolar transistor and a zener diode on its base (q2 and dz), and smoothed by the capacitors c3 and c4. r15 polarizes the base of the transistor and at the same time limits the current through the zener diode during regulation mode of the auxilia- ry power supply. the current and voltage regulations are made thanks to the two operational amplifiers. the first amplifier senses the current flow through the sense resistor rs and compares it with a part of the reference voltage (resistor bridge r7, r8, r9). the second amplifier compares the reference voltage with a part of the chargers output (resistor bridge r1, r2, r3). when either of these two operational amplifiers tends to lower its ouput, this linear information is propagated towards the primary side via two or- ing diodes (d1, d2) and an optocoupler (d3). the compensation loops of these regulation functions are ensured by the capacitors c1 and c2. 1 2 3 14 15 16 5 6 7 12 11 10 v cc + vref cathode v cc - comp comp tsm102 application note a battery charger using the tsm102
tsm102/a 7/10 figure 2 : the application schematic - battery charger secondary side the first comparator ensures the low battery signal generation thanks to the comparison of a part of the chargers output voltage (resistor bridge r17, r19) and the reference voltage. prop- er hysteresis is given thanks to r20. an improve- ment to the chargers security and to the batterys life time optimization is achieved by lowering the current control measurement thanks to q1 that shunts the resistor r9 when the batterys voltage is below the low battery level. the second comparator ensures the end of charge signal generation thanks to the compari- son of a part of the chargers output voltage (resis- tor bridge r1, r2, r3) and the reference voltage. when either of these two signals is active, the cor- responding led is polarized for convenient visual- ization of the battery status. 3 - calculation of the elements all the components values have been chosen for a two-lithium-ion batteries charge application : n current control : 720ma (low battery current control : 250ma) n voltage control : 8.4v (= 2x 4.2v) n low battery : 5.6v (= 2x 2.5v + 0.6v) n end of charge : 8.3v (= 2x 4.15v) current control : the voltage reference is polarized thanks to the r4 resistor (2.5ma), and the cathode of the refer- ence gives a fixed 2.500v voltage. i = u / r = [v ref ( r8 + r9 ) / (r7 + r8 + r9) ] / rs = [2.5 x (390 + 820) / (10000 + 390 + 820)] / 0.375 = 720ma i = 720ma p = power dissipation through the sense resistor = r i2 = 0.375 x 0.7202 = 194mw in case of low battery conditions, the current control is lowered thanks to the following equation : i = u / r = [ v ref r8 / (r7 + r8) ] / rs = [ 2.5 x 390 / (10000 + 390 ) ] / 0.375 = 250ma i (lobatt) = 250ma voltage control : v out = v ref / [ r2 / (r1 + r2 + r3) ] = 2.5 / [ 56 / (131.5 + 56 + 0.68 ) ] = 8.400v v out = 8.400v low battery signal : if r5 = 0 w and r6 = open : v out (lobatt) = vref / [ r19 / ( r17 + r19 ) ] = 2.5 / [ 10 / (12.4 + 10) ] = 5.6v v out (lobatt) = 5.6v end of charge signal : v out (eoc) = vref / [ (r2 + r3 ) / (r1 + r2 + r3) ] = 2.5 / [(56 + 0.68) / (131.5 + 56 + 0.68)] = 8.300v v out (eoc)= 8.300v
tsm102/a 8/10 notes: the current control values must be chosen in ac- cordance with the elements of the primary side. the performances of the battery charger in their globality are highly dependent on the adequation of the primary and the secondary elements. the addition of the diode d9 is necessary to avoid dramatic discharge of the battery cells in case of the charger disconnection from the mains voltage, and therefore, the voltage measurement is to be operated on the cathode side of the diode not to take its voltage drop into account. the total bridge value of r1, r2, r3 must ensure low battery dis- charge if the charger is disconnected from main, but remains connected to the battery by mistake. the chosen values impose a 44 m a discharge cur- rent max. r12 and r13 are the equivalent resistors seen from the opamp and from the comparator. a hysteresis resistor can be connected to the end of charge comparator to ensure proper hystere- sis to this signal, but this resistor must be chosen carefully not to degrade the output voltage preci- sion. it might be needed to impose unidirectionnal hysteresis (by inserting a diode on the positive feedback of the comparator). figure 3 shows how to use the integrated voltage reference to build a precise power supply for the tsm102a (and other components if necessary). pin 8 remains the reference for all voltage mea- surements for the rest of the application. figure 3 : a precise power supply for the tsm102a and other components v aux tsm102 vref vcc + 9 vaux 13 8 +
tsm102/a 9/10 package mechanical data 16 pins - plastic package dim. millimeters inches min. typ. max. min. typ. max. a1 0.51 0.020 b 0.77 1.65 0.030 0.065 b 0.5 0.020 b1 0.25 0.010 d 20 0.787 e 8.5 0.335 e 2.54 0.100 e3 17.78 0.700 f 7.1 0.280 i 5.1 0.201 l 3.3 0.130 z 1.27 0.050
tsm102/a information furnished is believed to be accurate and reliable. however, stmicroelectronics assumes no responsibility for the co nsequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of stmicroelectronics. specifications mentioned in this publicati on are subject to change without notice. this publication supersedes and replaces all information previously supplied. stmicroelectronics prod ucts are not authorized for use as critical components in life support devices or systems without express written approval of stmicroelectro nics. ? the st logo is a registered trademark of stmicroelectronics ? 2001 stmicroelectronics - printed in italy - all rights reserved stmicroelectronics group of companies australia - brazil - china - finland - france - germany - hong kong - india - italy - japan - malaysia - malta - morocco singapore - spain - sweden - switzerland - united kingdom ? http://www.st.com 10/10 package mechanical data 16 pins - plastic micropackage (so) dim. millimeters inches min. typ. max. min. typ. max. a 1.75 0.069 a1 0.1 0.2 0.004 0.008 a2 1.6 0.063 b 0.35 0.46 0.014 0.018 b1 0.19 0.25 0.007 0.010 c 0.5 0.020 c1 45 (typ.) d 9.8 10 0.386 0.394 e 5.8 6.2 0.228 0.244 e 1.27 0.050 e3 8.89 0.350 f 3.8 4.0 0.150 0.157 g 4.6 5.3 0.181 0.209 l 0.5 1.27 0.020 0.050 m 0.62 0.024 s 8 (max.)
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