general description the MAX5420 and max5421 are digitally programmable precision voltage dividers optimized for use in digitally pro- grammable gain amplifier configurations. the MAX5420/ max5421 operate from a single +5v supply or dual ?v supply, and consume only 3? supply current. these devices consist of a digitally selectable resistor array that provides four precision noninverting gains of 1, 2, 4, and 8 for pgas. the MAX5420 and max5421 achieve a resistor ratio accuracy of 0.025% (max542_a), 0.09% (max542_b), and 0.5% (max542_c). the max5421 includes an on-chip matching resistor for op amp bias-current compensation. the MAX5420 and max5421 are available in 8-pin and 10-pin ?ax packages. the devices are specified over the extended temperature range (-40? to +85?). applications general-purpose programmable noninverting amplifiers programmable instrumentation amplifiers features four precision divider ratios for noninverting gains of 1, 2, 4, and 8 in pgas 0.025%, 0.09%, or 0.5% ratio accuracy guaranteed over -40? to +85? on-chip matching resistor for op amp bias- current compensation (max5421) 5v single or ?v dual supply operation low 3? supply current cmos/ttl logic compatible 2-wire parallel interface small 8-pin and 10-pin ?ax packages MAX5420/max5421 digitally programmable precision voltage divider for pgas ________________________________________________________________ maxim integrated products 1 l d1 d0 1 2 8 7 h w v ss gnd v dd max-8 top view 3 4 6 5 MAX5420 1 2 3 4 5 10 9 8 7 6 h w l match_h d0 gnd v ss v dd max5421 max-10 match_l d1 pin configurations ordering information functional diagram 19-2229; rev 1; 7/03 part temp range pin- package gain accuracy MAX5420 aeua -40 c to +85 c 8 max 0.025% MAX5420beua -40 c to +85 c 8 max 0.09% MAX5420ceua -40 c to +85 c 8 max 0.5% max5421 aeub -40 c to +85 c 10 max 0.025% max5421beub -40 c to +85 c 10 max 0.09% max5421ceub -40 c to +85 c 10 max 0.5% decoder match_h match_l max5421 only h v dd w l gnd v ss MAX5420 max5421 d0 d1 for pricing, delivery, and ordering information, please contact maxim/dallas direct! at 1-888-629-4642, or visit maxim? website at www.maxim-ic.com. www.datasheet.co.kr datasheet pdf - http://www..net/
MAX5420/max5421 digitally programmable precision voltage divider for pgas 2 _______________________________________________________________________________________ absolute maximum ratings electrical characteristics (v dd = +5v 5%, v ss = -5v 5% or v ss = gnd, t a = t min to t max , unless otherwise noted. typical values are at t a = +25 c.) stresses beyond those listed under ?bsolute maximum ratings?may cause permanent damage to the device. these are stress rating s only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specificatio ns is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. v dd to gnd ..............................................................-0.3v to +6v v ss to gnd...............................................................+0.3v to -6v d0, d1 to gnd ...........................................-0.3v to (v dd + 0.3v) h, l, w, match_ to gnd ................(v ss - 0.3v) to (v dd + 0.3v) input and output latchup immunity.................................50ma continuous power dissipation (t a = +70 c) 8-pin max (derate 4.1mw/ c above +70 c) .............333mw 10-pin max (derate 5.6mw/ c above +70 c) ...........444mw operating temperature range ...........................-40 c to +85 c storage temperature range .............................-60 c to +150 c lead temperature (soldering, 10s) .................................+300 c parameter symbol conditions min typ max units max542_a 0.025 max542_b 0.09 divider ratio accuracy max542_c 0.5 % h-to-l resistance r hl (figure 1) 15 k ? input resistance at h r h 15 k ? v ss = -5v 300 ratio = 1 v ss = 0 500 ? input resistance at w r w ratio = 2, 4, 8 8 k ? capacitance at h, l, w, match_h, match_l c analog 5pf v ss = -5v 300 ratio = 1 v ss = 0 500 ? matching resistor max5421 ratio = 2, 4, 8 8 k ? dynamic performance switching time t s v d d = + 5v , v s s = - 5v , d i g i tal i np ut 0 to + 3v , v w settl es to 0.02% of fi nal val ue w i th 2p f cap aci ti ve l oad . c i r cui t of fi g ur e 2. 0.5 s digital inputs input high voltage v ih 2.4 input low voltage v il 0.8 v input leakage current d1, d0 = v dd or gnd 1 a input capacitance 5pf www.datasheet.co.kr datasheet pdf - http://www..net/
MAX5420/max5421 digitally programmable precision voltage divider for pgas _______________________________________________________________________________________ 3 electrical characteristics (continued) (v dd = +5v 5%, v ss = -5v 5% or v ss = gnd, t a = t min to t max , unless otherwise noted. typical values are at t a = +25 c.) parameter symbol conditions min typ max units power supplies positive supply voltage v dd 4.75 5.25 negative supply voltage v ss 0 -5.25 v d1, d0 = v dd or gnd 3 7 positive supply current i dd d1, d0 = 3v 15 25 a d1, d0 = v dd or gnd 3 7 negative supply current i ss d1, d0 = 3v 15 25 a w, h, l, match_l, match_h voltage range v ss v dd v typical operating characteristics (v dd = +5v, v ss = -5v, or v ss = gnd, t a = +25 c, unless otherwise noted.) (note 1) 0.0001 0.0004 0.0007 0.0010 max542_a divider ratio accuracy vs. temperature MAX5420/21 toc01 temperature ( c) ratio accuracy (%) -40 -15 10 35 60 85 v h = +5v v l = -5v ratio = 1 0.0030 0.0034 0.0042 0.0038 0.0046 0.0050 -40 10 -15 35 60 85 max542_a divider ratio accuracy vs. temperature MAX5420/21 toc02 temperature (c) ratio accuracy (%) v h = +5v v l = -5v ratio = 2 0 0.001 0.003 0.002 0.004 0.005 -40 10 -15 35 60 85 max542_a divider ratio accuracy vs. temperature MAX5420/21 toc03 temperature ( c) ratio accuracy (%) v h = +5v v l = -5v ratio = 4 www.datasheet.co.kr datasheet pdf - http://www..net/
MAX5420/max5421 digitally programmable precision voltage divider for pgas 4 _______________________________________________________________________________________ 0 0.002 0.001 0.004 0.003 0.006 0.005 0.007 -40 10 -15 35 60 85 max542_a divider ratio accuracy vs. temperature MAX5420/21 toc04 temperature ( c) ratio accuracy (%) v h = +5v v l = -5v ratio = 8 0.0020 0.0015 0.0010 0.0005 0 -40 10 -15 356085 max542_b divider ratio accuracy vs. temperature MAX5420/21 toc05 temperature ( c) ratio accuracy (%) v h = +5v v l = -5v ratio = 1 -0.0200 -0.0225 -0.0250 -0.0275 -0.0300 -40 10 -15 35 60 85 max542_b divider ratio accuracy vs. temperature MAX5420/21 toc06 temperature (c) ratio accuracy (%) v h = +5v v l = -5v ratio = 2 -0.030 -0.035 -0.040 -0.045 -0.050 -40 10 -15 35 60 85 max542_b divider ratio accuracy vs. temperature MAX5420/21 toc07 temperature ( c) ratio accuracy (%) v h = +5v v l = -5v ratio = 4 -0.050 -0.055 -0.060 -0.065 -0.070 -40 10 -15 35 60 85 max542_b divider ratio accuracy vs. temperature MAX5420/21 toc08 temperature ( c) ratio accuracy (%) v h = +5v v l = -5v ratio = 8 0.01 0.0001 4.75 5.00 5.25 max542_a ratio accuracy vs. positive supply voltage MAX5420/21 toc09 positive supply voltage (v) ratio accuracy (%) 0.001 v h = +3v, v l = 0 ratio = 4 ratio = 2 ratio = 1 ratio = 8 0.1 0.0001 4.75 5.00 5.25 max542_b ratio accuracy vs. positive supply voltage MAX5420/21 toc10 positive supply voltage (v) ratio accuracy (%) 0.01 0.001 v h = +3v, v l = 0 ratio = 2 ratio = 1 ratio = 4 ratio = 8 0.01 0.0001 -5.25 -2.75 -0.25 max542_a ratio accuracy vs. negative supply voltage MAX5420/21 toc11 negative supply voltage (v) ratio accuracy (%) 0.001 -4.00 -1.50 v h = 5v, v l = 0 ratio = 8 ratio = 4 ratio = 1 ratio = 2 0.1 0.01 0.0001 -5.25 -2.75 -0.25 max542_b ratio accuracy vs. negative supply voltage MAX5420/21 toc12 negative supply voltage (v) ratio accuracy (%) 0.001 -4.00 -1.50 ratio = 1 v h = 5v, v l = 0 ratio = 8 ratio = 2 ratio = 4 typical operating characteristics (continued) (v dd = +5v, v ss = -5v, or v ss = gnd, t a = +25 c, unless otherwise noted.) (note 1) www.datasheet.co.kr datasheet pdf - http://www..net/
MAX5420/max5421 digitally programmable precision voltage divider for pgas _______________________________________________________________________________________ 5 100ns/div v h = +5v, v l = -5v switching time (ratio 1-to-2) v w 2v/div MAX5420/21 toc13 d0, 5v/div 0 100ns/div v h = +5v, v l = -5v switching time (ratio 2-to-4) v w 1v/div MAX5420/21 toc14 d1, 5v/div 0 100ns/div v h = +5v, v l = -5v switching time (ratio 4-to-8) v w 500mv/div 5v MAX5420/21 toc15 d0, 5v/div 0 0 1 3 2 4 5 -40 10 -15 35 60 85 supply current vs. temperature MAX5420/21 toc16 temperature ( c) supply current ( a) d1, d0 = gnd or v dd typical operating characteristics (continued) (v dd = +5v, v ss = -5v, or v ss = gnd, t a = +25 c, unless otherwise noted.) (note 1) note 1: for max542_c accuracy typical operating characteristics , refer to max542_b accuracy typical operating characteristics . www.datasheet.co.kr datasheet pdf - http://www..net/
MAX5420/max5421 detailed description the MAX5420/max5421 are digitally programmable pre- cision voltage dividers for programmable-gain amplifiers. operationally, these devices consist of digitally selectable precision resistor-dividers providing noninverting gains of 1, 2, 4, and 8 for pga applications (see functional diagram and figure 1 ). the MAX5420/max5421 achieve divider ratio accuracy of 0.025% (MAX5420a/max5421a), 0.09% (MAX5420b/ max5421b) or 0.5% (MAX5420c/max5421c). the end-to-end resistance from h to l is 15k ? . the impedance seen at w is designed to be the same 8k ? for divider ratios 2, 4, and 8, ensuring excellent imped- ance matching and constant switching times. in gain of +1 configuration, h is internally connected to w with a typical resistance of 500 ? . matching resistor (max5421) the max5421 includes a matching resistor to compen- sate for offset voltage due to input bias current of the op amp. the resistance from match_h to match_l, equals the resistance seen at w for gains of 2, 4, and 8. in the gain of +1, an internal switch connects match_h and match_l. this internal switch matches the impedance of the switch between h and w. digital interface operation the MAX5420/max5421 feature a simple two-bit paral- lel programming interface. d1 and d0 program the divider ratio setting according to the logic control truth table (table 1). the digital interface is cmos/ttl logic compatible. applications information programmable-gain amplifier the MAX5420/max5421 are ideally suited for high-pre- cision pga applications. the typical application circuit of figure 3 uses the max5421 with matching resistor to compensate for voltage offset due to op amp input bias currents. use the MAX5420 with an ultra-low input bias current op amp such as the max4237 (figure 4). power supplies and bypassing the MAX5420/max5421 operate from dual 5v sup- plies, or a single +5v supply. for dual supplies, bypass v dd and v ss with 0.1f ceramic capacitors to gnd. for single supply, connect v ss to gnd and bypass v dd with a 0.1f ceramic capacitor to gnd. ratio rb ra =+ 1 _ _ digitally programmable precision voltage divider for pgas 6 _______________________________________________________________________________________ digital inputs d1 d0 divider ratio 00 1 01 2 10 4 11 8 table 1. logic control truth table pin MAX5420 max5421 name function 11v dd positive supply voltage 22 v ss negative supply voltage 3 3 gnd ground 4, 5 4, 5 d0, d1 digital control inputs. drive d0 and d1 logic high or logic low to set the divider ratio. see logic control truth table . 6 8 l low terminal of resistor-divider 7 9 w resistor-divider output 8 10 h high terminal of resistor-divider 6 match_l matching resistor low terminal 7 match_h matching resistor high terminal pin description www.datasheet.co.kr datasheet pdf - http://www..net/
switching time and layout concerns the switching time of the MAX5420/max5421 depends on the capacitive loading at w. for best performance, reduce parasitic board capacitance by minimizing the circuit board trace from w to the op amp inverting input, and choose an op amp with low input capacitance. chip information transistor count: 118 process: cmos MAX5420/max5421 digitally programmable precision voltage divider for pgas v out +5v match_l h v dd +5v match_h l v ss w gnd max5421 v in max4493 h w l gnd +5v +5v MAX5420 v dd v ss v in max4237 v out figure 3. programmable-gain amplifier with op amp bias- current matching figure 4. programmable-gain amplifier r1a r2a r3a l h r3b r2b r1b ratio = 1 ratio = 2 ratio = 4 ratio = 8 w ratio = r_b r_a 1+ ( ) figure 1. simplified functional diagram r1a r2a r3a l h r3b r2b r1b ratio = 1 ratio = 2 ratio = 4 ratio = 8 w ratio = r_b r_a 1+ ( ) 0.1 f +5v v dd 0.1 f -5v v ss gnd pulse generator d1 d0 max5421 tektronix p6245 oscilloscope fet probe c l < 1pf 1m ? figure 2. switching time test circuit _______________________________________________________________________________________ 7 www.datasheet.co.kr datasheet pdf - http://www..net/
MAX5420/max5421 digitally programmable precision voltage divider for pgas 8 _______________________________________________________________________________________ 8lumaxd.eps package outline, 8l umax/usop 1 1 21-0036 j rev. document control no. approval proprietary information title: max 0.043 0.006 0.014 0.120 0.120 0.198 0.026 0.007 0.037 0.0207 bsc 0.0256 bsc a2 a1 c e b a l front view side view e h 0.60.1 0.60.1 ? 0 .500.1 1 top view d 8 a2 0.030 bottom view 1 6 s b l h e d e c 0 0.010 0.116 0.116 0.188 0.016 0.005 8 4x s inches - a1 a min 0.002 0.950.75 0.5250 bsc 0.25 0.36 2.95 3.05 2.95 3.05 4.78 0.41 0.65 bsc 5.03 0.66 60 0.13 0.18 max min millimeters - 1.10 0.05 0.15 dim package information (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation go to www.maxim-ic.com/packages .) www.datasheet.co.kr datasheet pdf - http://www..net/
MAX5420/max5421 digitally programmable precision voltage divider for pgas 10lumax.eps package outline, 10l umax/usop 1 1 21-0061 i rev. document control no. approval proprietary information title: top view front view 1 0.498 ref 0.0196 ref s 6 side view bottom view 0 0 6 0.037 ref 0.0078 max 0.006 0.043 0.118 0.120 0.199 0.0275 0.118 0.0106 0.120 0.0197 bsc inches 1 10 l1 0.0035 0.007 e c b 0.187 0.0157 0.114 h l e2 dim 0.116 0.114 0.116 0.002 d2 e1 a1 d1 min -a 0.940 ref 0.500 bsc 0.090 0.177 4.75 2.89 0.40 0.200 0.270 5.05 0.70 3.00 millimeters 0.05 2.89 2.95 2.95 - min 3.00 3.05 0.15 3.05 max 1.10 10 0.60.1 0.60.1 ? 0.500.1 h 4x s e d2 d1 b a2 a e2 e1 l l1 c gage plane a2 0.030 0.037 0.75 0.95 a1 package information (continued) (the package drawing(s) in this data sheet may not reflect the most current specifications. for the latest package outline info rmation go to www.maxim-ic.com/packages .) maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a maxim product. no circuit patent licenses are implied. maxim reserves the right to change the circuitry and specifications without notice at any time. maxim integrated products, 120 san gabriel drive, sunnyvale, ca 94086 408-737-7600 _____________________ 9 ? 2003 maxim integrated products printed usa is a registered trademark of maxim integrated products. www.datasheet.co.kr datasheet pdf - http://www..net/
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