1 of 9 112099 features compatible with ds1229 5v operation 20-pin dip or soic package 20-pin tssop package for height restricted applications operate from single +5v power meets all eia-232e and v.28 specifications uses small capacitors: 0.1 f optional industrial temperature range available (-40 c to +85 c) ordering information ds229 20-pin dip ds229n 20-pin dip (industrial) ds229s 20-pin soic ds229sn 20-pin soic (industrial) ds229e 20-pin tssop ds229en 20-pin tssop (industrial) pin assignment pin description v cc - +5-volt supply gnd - ground v+ - positive supply output v- - negative supply output t1 in , t2 in , t3 in - rs-232 driver inputs t1 out , t2 out , t3 out - rs-232 driver outputs r1 in , r2 in , r3 in - receiver inputs r1 out , r2 out , r3 out - receiver outputs c1+, c1- - capacitor 1 connections c2+, c2- - capacitor 2 connections description the ds229 is a triple rs-232 driver/receiver pair that generates rs-232 voltage levels from a single +5- volt power supply. additional 12-volt supplies are not needed since the ds229 uses on-board charge pumps to convert the +5-volt supply to 10 volts. the ds229 is fully compliant with eia rs-232e and v.28/v.24 standards. the ds229 contains three drivers and three receivers. driver slew rates and data rates are guaranteed up to 116 kbits/sec. the ds229 operates with only 0.1 f charge pump capacitors. operation the diagram in figure 1 shows the main elements of the ds229. the following paragraphs describe the function of each pin. ds229 triple rs-232 transmitter/receive r www.dalsemi.com 20-pin dip, soic and tssop 19 c1- c2- t2 ou t r2 in t3 out r3 in v cc r1 in r1 out t1 in t2 in r2 out t3 in r3 out 1 2 3 4 5 6 7 8 9 10 20 18 17 16 15 14 13 12 11 v+ c2+ v- c1+ gnd t1 out
ds229 2 of 9 functional diagram of ds229 figure 1 note: c5 is a recommended decoupling capacitor which is the same value as c1, c2, c3, and c4. pin descriptions v cc , gnd: dc power is provided to the device on these pins. v cc is the +5-volt input. v+: positive supply output (rs-232). v+ requires an external storage charge capacitor of at least 0.1 f. a larger capacitor (up to 10 f) can be used to reduce supply ripple.
ds229 3 of 9 v-: negative supply output (rs-232). v- requires an external storage capacitor of at least 0.1 f. a larger capacitor (up to 10 f) can be used to reduce supply ripple. t1 in , t2 in , t3 in : standard ttl/cmos inputs for the rs-232 drivers. the inputs of unused drivers can be left unconnected since each input has a 400 k ? pullup resistor. t1 out , t2 out , t3 out : driver outputs at rs-232 levels. driver output swing meets rs-232 levels for loads up to 3 k ? . these driver outputs provide current necessary to meet rs-232 levels for loads up to 2500 pf. r1 in , r2 in , r3 in : receiver inputs. these inputs accept rs-232 level signals (25 volts) into a protected 5 k ? terminating resistor. each receiver provides 0.5v hysteresis (typical) for noise immunity. r1 out , r2 out , r3 out : receiver outputs at ttl/cmos levels. c1+, c1-, c2+, c2-: charge pump capacitor inputs. these pins require two external capacitors (0.1 f minimum, 10 f maximum and should be the same size as c3 and c4). capacitor 1 is connected between c1+ and c1-. capacitor 2 is connected between c2+ and c2-. capacitor c1 can be omitted if +12 volts is connected directly to v+. likewise, c2 can be omitted if -12v is connected directly to v-. dual charge pump converters the ds229 has a two stage on-board charge pump circuit that is used to generate 10 volts from a single +5-volt supply. in the first stage, capacitor c1 doubles the +5v supply to +10 volts which is then stored on capacitor c3. the second stage uses capacitor c2 to invert the +10v potential to -10v. this charge is then stored on capacitor c4. the 10-volt supplies allow the ds229 to provide the necessary output levels for rs-232 communication. the ds229 will operate with charge pump capacitors as low as 0.1 f. larger capacitors (up to 10 f) can be used to reduce supply ripple. rs-232 drivers the three rs-232 drivers are powered by the internal 10-volt supplies generated by the on-board charge pump. the driver inputs are both ttl and cmos compatible. each input has an internal 400 k ? = pullup resistor so that unused transmitter inputs can be left unconnected. the open circuit output voltage swing is from (v+ - 0.6) to v- volts. worst case conditions for eia-232e/v.28 of 5 volts driving a 3 k ? = load and 2500 pf are met at maximum operating temperature and v cc equal to 4.5 volts. typical voltage swings of 8 volts occur when loaded with a nominal 5 k ? = rs-232 receiver. as required by eia-232e and v.28 specifications, the slew rate at the output is limited to less than 30 volts/ s. typical slew rates are 20 volts/ s unloaded and 12 volts/ s with 3 k ? = and 2500 pf load. these slew rates allow for bit rates of over 116 kbits/s. driver outputs maintain high impedance when power is off. rs-232 receivers the three receivers conform fully to the rs-232e specifications. the input impedance is typically 5 k ? = and can withstand up to 30 volts with or without v cc applied. the input switching thresholds are within the 3-volt limit of rs-232e specification with an input threshold low of 0.8 volts and an input threshold high of 2.4 volts. the receivers have 0.5 volts of hysteresis (typical) to improve noise rejection. the ttl/cmos compatible outputs of the receivers will be low whenever the rs-232 input is greater than 2.4 volts. the receiver output will be high when the input is floating or driven between +0.8 volts and -25 volts.
ds229 4 of 9 absolute maximum ratings* absolute maximum ratings v cc -0.3v to +7.0v v+ (v cc -0.3v) to +14v v- +0.3v to -14v input voltages t in -0.3v to (v cc +0.3v) r in 30v output voltages t out (v+ + 0.3v) to (v- - 0.3v) r out -0.3v to (v cc + 0.3v) short circuit duration, t out continuous * this is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. exposure to absolute maximum rating conditions for extended periods of time may affect reliability. recommended dc operating conditions (0 c to 70 c) parameter symbol min typ max units notes operating supply voltage v cc 4.5 5.5 v 1 dc electrical characteristics (0 c to 70 c) parameter symbol min typ max units notes power supply current (no load) i cc1 615ma power supply current (3 k ? load all outputs) i cc2 22.5 ma rs-232 transmitters output voltage swing v ors 5 8 v2 input logic threshold low v ttl 0.8 1.4 v input logic threshold high v tth 1.4 2.0 v data rate f d 200 116 kbits/s logic pullup/input current i pu 540 a transmitter output resistance r out 300 10m ? 3 output short-circuit current i tsc 15 30 100 ma 4
ds229 5 of 9 dc electrical characteristics (continued) (0 c to 70 c) rs-232 receivers rs-232 input voltage operating range v ir 25 30 v rs-232 input threshold low v rtl 0.8 1.3 v rs-232 input threshold high v rth 1.8 2.4 v rs-232 input hysteresis v hy 0.2 0.5 1 v rs-232 input resistance r in 357 k ? ttl/cmos output voltage low v rol 0.2 0.4 v 5 ttl/cmos output voltage high v roh 3.5 v cc -0.2 v 6 ttl/cmos output short circuit current (v out =gnd) i rsc -2 -10 ma ttl/cmos output short circuit current (v out =v cc ) i rsc 10 30 ma ac electrical characteristics (0 c to 70 c) parameter symbol min typ max units notes transition slew rate t sr 61230 v/ s 7 transmitter propagation delay ttl to rs-232 t phlt t plht 1.3 1.5 3.5 3.5 s s receiver propagation delay rs-232 to ttl t phl r t plhr 0.5 0.6 1 1 s s transmitter + to - propagation delay difference t phlt -t plht 300 ns receiver + to - propagation delay difference t phl r -t plhr 100 ns notes: 1. all voltages are referenced to ground. 2. all transmitter outputs loaded with 3 k ? = to ground 3. v cc = v+ = v- = 0v; v out = 2v. 4. v out = 0v. 5. i out = 3.2 ma. 6. i out = -1.0 ma. 7. c l = 50 pf - 2500 pf; rl = 3 k ? = - 7 k ? ; v cc = 5v; ta = 25 c.
ds229 6 of 9 transmitter propagation delay timing figure 2 receiver propagation delay timing figure 3
ds229 7 of 9 20-pin dip (300-mil) pkg 20-pin dim min max a in. mm 0.970 24.63 1.040 26.42 b in. mm 0.240 6.09 0.270 6.86 c in. mm 0.120 3.05 0.140 3.56 d in. mm 0.295 7.49 0.325 8.26 e in. mm 0.015 0.38 0.040 1.02 f in. mm 0.120 3.04 0.140 3.56 g in. mm 0.090 2.23 0.110 2.79 h in. mm 0.310 7.87 0.390 9.91 j in. mm 0.008 0.20 0.012 0.30 k in. mm 0.015 0.38 0.021 0.53
ds229 8 of 9 20-pin soic (300-mil) pkg 20-pin dim min max a in. mm 0.094 2.39 0.105 2.67 a1 in. mm 0.004 0.102 0.012 0.30 a2 in. mm 0.089 2.26 0.095 2.41 b in. mm 0.013 0.33 0.020 0.51 c in. mm 0.009 0.229 0.013 0.33 d in. mm 0.498 12.65 0.511 12.99 e in. mm 0.050 bsc 1.27 bsc e1 in. mm 0.290 7.37 0.300 7.62 h in. mm 0.398 10.11 0.416 10.57 l in. mm 0.016 0.40 0.040 1.02 0 8
ds229 9 of 9 20-pin tssop dim min max a mm -1.10 a1 mm 0.05 - a2 mm 0.75 1.05 c mm 0.09 0.18 l mm 0.50 0.70 e1 mm 0.65 bsc b mm 0.18 0.30 d mm 6.40 6.90 e mm 4.40 nom g mm 0.25 ref h mm 6.25 6.55 phi 0 8
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