19-0015; Rev 0; 5/92 MAKIM +3.3V Transceiver with Two EIA/TIA-562 Receivers Active in Shutdown General Description The MAX560/MAX561 are the first +3.3V-powered devices to implement the EIA/TIA-562 standard, which guarantees interoperability with RS-232 interfaces. The MAX560/MAX561 are guaranteed to operate with a +3.0V power supply at a 20kbits/sec data rate while maintaining +3.7V EIA/TIA-562 signal levels. The MAX560/MAX561 include four line drivers, five re- ceivers, a shutdown mode, and a receiver-enable input. An on-board charge-pump voltage converter converts the +3.3V input to the +6.6V needed to comply with the EIA/TIA-562 output levels. The MAX560 has an active- low shutdown and an active-high receiver enable. In shutdown mode, two receivers are active, allowing uni- directional communication for peripheral monitoring. The Features @ 2 Receivers Active in Shutdown Mode (MAX560) @ Small 28-pin SSOP Package 40% the Area of SO Package @ Guaranteed Interoperability with RS-232 @ Operate from a Single +3.0V to +3.6V Supply @ Designed for ElA/TIA-562 Applications @ 4 Drivers/5 Receivers @ Low-Power Shutdown: <8A MAX560 < 1A MAX561 @ Three-State TTL/CMOS Receiver Outputs 116kbits/sec Data Rate MAX561 has an active-high shutdown and an active-low Ordering information receiver enable. In shutdown mode, all receivers are ina . high-impedance, three-state mode. PART TEMP. RANGE PIN-PACKAGE | The MAX560/MAX561 are available in a standard 28-pin MAX560CWI OC 10 +70C 28 Wide SO wide small outline (SO) package and a 28-pin shrink > 3 small outline package (SSOP), which requires 40% of the MAXS60CA\ oc to +70C 28 ssoP board space of the SO package. Each operates with four MAXS60C/D OC to +70C Dice 1pF capacitors, further reducing board space. MAX561CWl 0C to +70C 28 Wide SO A pplications MAX561CAI OC to +70C 28 SSOP MAX561C/D 0C to +70C Dice* Laptop Computers Palmtop Computers *Dice are specified at Ta = +25C. Notebook Computers Battery-Powered Equipment Pin Configurations TOP VIEW Tour [4 | * 28] Tour Taout [| * j28) Tour Tour [2 | 127] Ran Tour [2] [27] Ra Tout [3 | [26] R30ur Teour (3 | Rout Pw [a | 125] SHON Raw [4 | 125] SHDN R2our [5 | 24] EN R2our [5 | 2a] EN Tan [6] AA ALAA [23] Pan: tin [7] MAX560 To0] Raour- Tin [7] MAXS67 [2a] Rour Rtour [8 | at] Taw Rout 21) Tan Ri [9] [20] Tan Rin [9 | 20] T3N GND [10] 119] Rour- GND 119] R5our vec [14] 18] ASIN Vee 18] RSW crs [re 7] v- cts [12] 7] v= ve [13] 16] C2- ve [13] 16] C2- * ACTIVE IN SHUTDOWN ct 15] C24 SO/SSOP c1- fal 5] 024 Tan [6] AnarcrAa|zs] Pan Typical operating circuit on last page MAKIN Maxim Integrated Products. 1 Cail toll free 1-800-998-8800 for free samples or literature. L9SXVW/O9SXUWMAXS560/MAX561 +3.3V Transceiver with Two EIA/TIA-562 Receivers Active in Shutdown ABSOLUTE MAXIMUM RATINGS VOC ccc cece cette eee e teeter nents -0.3V to +6V VE ce ete (Voc - 0.3V) to +14V oC +0.3V to -14V Input Voltages TIN occ ccc cate ce eee ee ete et ence ees 0.3V to (Vcc + 0.3V) LL +25V Output Voltages TOUT ooo center tees (V+ + 0.3V) to (V- - 0.3V) ROUT ooo ccc ccc ence nett eee aes -0.3V to (Vcc + 0.3V) Stresses be Short-Circuit Duration TOUT octet eee enter eee es Continuous Continuous Power Dissipation Wide SO (derate 12.50mW/"C above +70C) ...... {000mWw SSOP (derate 9.52mW/C above +70C)........... 762mW Operating Temperature Range................ 0C to +70C Storage Temperature Range .............. -65C to +160C Lead Temperature (soldering, 10sec) .............. +300C d those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (Vcc = +3.0V to +3.6V, C1 - C4 = 1pF, Ta = 0C to +70C, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX | UNITS ante and pyeuts loaded with 3kQ to ground +37 44.2 Output Voltage Swing Vv Vcc = 3.3V, 4 transmitter outputs loaded with 3kQ to ground 43.7 44.5 Vcc Power-Supply Current No load, Ta = +25C 8 mA Shutdown Supply Current Figure 1, Ta = +25C MAXS60 8 50 pA MAX561 1 10 Input Logic Threshold Low Tin, EN, SHDN (MAX560), SHDN (MAX561) 0.4 Vv Input Logic Threshold High Tin, EN, SHDN (MAX560), SHDN (MAX561) 2.4 V Logic Pull-Up Current TIN = OV 6 135 pA Receiver Input Voltage Operating Range 725 25 Vv EJATIA-862 Input Threshold Low | Normal operation 04 __08 v SHDN = OV, (R4iN, R5IN) MAX560 0.4 1.4 EIA/TIA-562 Input Threshold High | Normal operation i 24 v SHDN = OV, (R4IN, RSIN) MAX560 1.4 2.4 EIA/TIA-562 Input Hysteresis No hysteresis when SHDN = OV MAX560 0.3 V EIA/TIA-562 Input Resistance Ta = +25C, Voc = 3.3V 3 5 7 kQ CMOS Output Voltage Low lout = 1.6mA 0.4 Vv CMOS Output Voltage High lout = -40nA 28 Voc - 0.1 Vv CMOS Output Leakage Current EN = Voc, OV s Rout s Vcc 0.05 +10 pA Output Enable Time Figure 2, Ta = +25C 800 ns Output Disable Time MAXS60 1500 ns MAX561 500 2 MAKI VI+3.3V Transceiver with Two EIA/TIA-562 Receivers Active in Shutdown ELECTRICAL CHARACTERISTICS (continued) (Vcc = 3.0V to 3.6V, C1 - C4 = tpF, Ta = 0C to +70C, unless otherwise noted.) PARAMETER CONDITIONS MIN TYP MAX UNITS Receiver IN to Normal operation 1.0 10 Propagation Delay eet a ws x e 60 ov tPHLS 4 40 ps - tPLHS 6 40 Instantaneous Slew Rate CL = 50pF, RL = 3kQ to 7kQ, Ta = +25C (Note 1) 30 Vius iti i RL = 3kQ, CL = 2500pF, Transition Region Slew Rate Measured from +3V to -3V or -3V to +3V 25 Vins Transmitter Output Resistance Voc = V+ = V- = OV, VouT = +2V 300 Q Receiver Out Short-Circuit Current +10 mA Note 1: Guaranteed by design Typical Operating Characteristics MAX560 MAX560 TRANSMITTER OUTPUTS WHEN V+, V- WHEN EXITING SHUTDOWN EXITING SHUTDOWN V+ 2 TRANSMITTER OUTPUTS: ov 1 HIGH, 1 LOW Ve eee SHON son ee SHON J SHUTDOWN +}4 TRANSMITTERS ON #4 je SHUTDOWN ->[< TRANSMITTERS ON. | 3 TRANSMITTERS LOADED WITH 3k II 2500pF 3 TRANSMITTERS LOADED WITH 3k0. Il 2500pF MAX560 TRANSMITTER OUTPUT AT RECEIVER PROPAGATION DELAY IN SHUTDOWN 160KBITS/SEC DRIVING 3 TRANSMITTERS TRANSMITTER INPUT RECEIVER INPUT ov TRANSMITTER OUTPUT RECEIVER OUTPUT 3 TRANSMITTERS LOADED WITH 3kQ2 I! 1000pF MIAAISVI 3 LOSXVW/O9SXUWMAX560/MAX561 +3.3V Transceiver with Two EIA/TIA-562 Receivers Active in Shutdown SLEW RATE (V/ps) VoL (V) Von (V) TRANSMITTER SLEW RATE vs. LOAD CAPACITANCE 6.0 TT Ta=+25C 55 L Voc = +3.3 TS \ Chota ue | 50 N eee . | TRANSMITTERS 45 Ne Spas | 35 ras! 25 0 500 1000 1500 2000 2500 LOAD CAPACITANCE (pF) TRANSMITTER OUTPUT VOLTAGE (Vou) vs. Veo 4TRANS- Ta=425C a MITTERS ~C1- C4 = uF ee ti NN NL 5k62 11 25000F SS 4.8 50 KY MN 1 TRANS- [> MITTER $2 }LORDED = 34 r TRANS- 3 TRANS- MITTER 56 warren LOADED 58 1 J 3.0 31 32 33 34 35 3.6 Vcc {) TRANSMITTER OUTPUT VOLTAGE (Von) vs. LOAD CAPACITANCE AT DIFFERENT DATA RATES -40 42 44 -46 46 bh 45 44 NK |A 43 1GOKBITS/SEC XK 42 SOKBITS/SEC N at 20KBITS/SEC || \ 4.0 [y= 425C Veco =+3.3V 3.9 F3 TRANSMITTERS LOADED WITH AL = 3kQ II LOAD CAPACITANCE \ 3.8 [C1 -C4 = 1pF a 3.7 ) L 0 500 10001500 2000 2500 LOAD CAPACITANCE (pF) Vou (V) OUTPUT VOLTAGE V+, V- Vou (v) Typical Operating Characteristics (continued) TRANSMITTER OUTPUT VOLTAGE (Von) vs. Voc 56 54 52 5.0 48 46 Ta=425C 44 =r 42 WITH 40 LOADED 3kO. II 25000F 30 31 32 33 34 35 36 Vec (V) OUTPUT VOLTAGE V+, V- vs. LOAD CURRENT 8 t TT 5 Ta a26C Voo=33V <= C1- C4 = td 4L SES 2 {| + ND , V+ LOADED, g EQUALLY __NOLOAD __NOLOAD J LOADED ON V+ ON V- 2 \ 4 | - | 4 LL = | 6 | ALL TRANSMITTERS UNLOADED -8 1 0 5 10 15 20 2 CURRENT (mA) TRANSMITTER OUTPUT VOLTAGE (Voi) vs. LOAD CAPACITANCE AT DIFFERENT DATA RATES T TT Ta= 425C 3.8 LV6C=+3.3V 73 TRANSMITTERS LOADED WITH RL = 3kQ2 Il LOAD CAPACITANCE 40 rot -C4= tur 4 | | La 2 | teoKerrsysec 4 |__ 80KBITS/SEC 44 ox BITS/SEC 46 NA 48 ah | 50 0 500 1000 1500 2000 2500 LOAD CAPACITANCE (pF) MAKIN+3.3V Transceiver with Two EIA/TIA-562 Receivers Active in Shutdown C+ Vee V+ \pF aa cy. Mara F te, Maser DF twe ap | 5 36 ~ T1T0 14 OV 4 neu OFS g OUT Aw] | = ovoRs3.ev [7 DRIVE { ~ la 5k | +3.6V OV(436V) {SHON GND = EN* __ INPUT +3.3V ov OUTPUT ENABLE TIME +2.8V RECEIVER 0.4V OUTPUT CL=150pF +3.3V EN* wv INPUT + |- OUTPUT DISABLE TIME RECEIVER TOON OUTPUTS R=1kQ | T Vor + 0.1V * NOTE: MAXS8O POLARITY IS INVERTED. Figure 1. MAX561 Shutdown-Current Test Circuit Figure 2. Receiver Output Enable and Disable Timing Pin Description PIN NAME FUNCTION 1, 2, 3, 28 T_OUT EIA/TIA-562 Voltage-Level Driver Outputs 4, 9, 18, 23, 27 FLIN EIA/TIA-562 Voltage-Level Receiver Inputs CMOS Receiver Outputs. When using the MAX560, receivers R4 and R65 are active 5, 8, 19, 22, 26 R_ouT in shutdown mode when EN = 1. When using the MAX561, all receivers are inactive in shutdown. 6,7, 20,21 | TAN CMOS Driver Inputs 10 GND Ground 11 Voc +3.0V to +3.6V Supply Voltage 12, 14 C14, C1- Terminals for positive charge-pump capacitor 13 V+ +2Vcc Voltage generated by the charge pump 15, 16 C2+, C2- Terminals for negative charge-pump capacitor 17 V- -2Vcc Voltage generated by the charge pump 24 EN (MAXS60) Receiver Enable Active high See Shutdown and Enable Control section. EN (MAX561) Active low 25 SHDN (MAX560 Shutdown Control Active low See Shutdown and Enable Control section. SHDN (MAX561) Detailed Description The MAX560/MAX561 consist of three sections: charge- pump voltage converters, transmitters (drivers), and receivers. Each section is described in detail below. +3.3V to +6.6V Dual Charge-Pump Voltage Converter The +3.3V to+6.6V conversion is performed by two charge- pump voltage converters (Figure 3). The first uses capacitor C1 to double the +3.3V to +6.6V, storing the +6.6V on the V+ output filter capacitor, C3. The second charge-pump voltage converter uses capacitor C2 to Active high invert the +6.6V to -6.6V, storing the -6.6V on the V- output filter capacitor, C4. In shutdown mode, V+ is internally connected to Vcc by a 1kQ pull-down resistor and V- is internally connected to ground by a 1kQ pull-up resistor. EIA/TIA-562 Drivers The drivers are inverting fevel translators that convert +3V logic input levels to EIA/TIA-562 voltage levels. The driver outputs are inverting since the EIA/TIA-562 specification defines a receiver input voltage level greater than +3V as a 0, and a voltage level less than -3V as a 1. With MAXAI VI. k9OSXVIW/O9SXUWMAX560/MAX561 +3.3V Transceiver with Two EIA/TIA-562 Receivers Active in Shutdown Table 1. Receiver Operation and Control Normal Operation MAX560 MAX561 SHDN = 1: receivers active (EN = 1), receivers inactive (EN = 0) SHDN = 0: __ receivers active (EN_= 0), receivers inactive (EN = 1) Shutdown Mode SHDN = 0: receivers R1-R3 inactive (EN = 1), receivers R4 and R65 active (EN = 1), receivers R1-R5 inactive (EN = 0) SHDN = 1: __ receivers inactive (EN = 0), receivers inactive (EN = 1) Vcc = +3.0V, the typical output voltage swing is 4.1V when driving three transmitters, each with the worst-case 3kQ load. Under such conditions, the output swing is guaranteed to meet the EIA/TIA-562 minimum specifica- tion of 3.7V output voltage swing. The open-circuit output voltage swings from (V+ - 0.6V) to V-. The inputs of unused driver sections should be con- nected to Vcc, but can be left unconnected; an internal 400kQ input pull-up resistor to Vcc will pull the inputs high, forcing unused transmitter outputs low. The input pull-up resistors typically source 6A; therefore, the driver inputs should be driven high or open circuited to minimize power-supply current in shutdown mode. When in the low-power shutdown mode, the driver out- puts are turned off and their leakage current is less than {pA with the driver output pulled to ground. The driver output leakage remains less than 1pA, even if the trans- mitter output is backdriven between OV and (VCC + 6V). Below -0.5V, the transmitter input is diode clamped to ground with a 1kQ series impedance. The transmitter input is also zener clarnped to approximately (VCC + 6V), with a 1kQ series impedance. EIA/TIA-562 Receivers The receivers convert +3.7V to +13.2V EIA/TIA-562 level signals to +3V logic output levels. The receiver outputs are inverting, maintaining compatibility with the driver outputs. Maxim has set guaranteed receiver input thresholds of 0.4V and 2.4V, which are significantly tighter than the +3.0V thresholds required by the EIA/TIA-562 specification. This allows the receivers to respond to +3V logic levels as well as EIA/TIA-562 levels. The MAX560/MAX561s guaranteed 0.4V lower threshold ensures that a receiver shorted to ground will have a logic 1 output. The 5kQ input resistance to ground ensures that a receiver with its input left open will also have a logic 1 output. The receivers have approximately 0.3V hysteresis. This provides clean output transitions, even with slow rise and fall time input signals with moderate amounts of noise and ringing. In shutdown, the MAX560 receivers R4 and R5 have no hysteresis. Shutdown and Enable Control! THE POLARITY OF THE RECEIVER ENABLE AND SHUTDOWN LOGIC LEVELS FOR THE MAX560 ARE THE INVERSE OF THOSE FOR THE MAX561. Table 1 shows the polarity of the shutdown and enable controls for the MAX560/MAX561. In shutdown mode, the MAX560/MAX561 charge pump is turned off, V+ is pulled down to Vcc, and V- is pulled to ground. Also, the receiver outputs are put into a high-impedance state (R4 and R5 status depend on the EN pin if using the MAX560) and the transmitter outputs are disabled. This drops the supply current to ap- proximately 8yA for the MAX560 and 1pA for the MAX561. The time required to exit shutdown is typically ims, as shown in the Typical Operating Characteristics graphs. 84 GND ot oe Veco V+ V+ $1 C1+ $2 $5 C2+ $6 Veco \ . ; T oe ! + + ! + tS 03 SS i] Rit | C2 aN ct ( 1 i 1 ' GND #_0"! 0 @o GND C2- $8 ! 1 1 l 1 1 1 1 1 | Figure 3. Charge Pump 6 MAKIM+3.3V Transceiver with Two EIA/TIA-562 Receivers Active in Shutdown Applications Information Capacitor Selection The type of capacitor used is not critical for proper MAX560/MAX561 operation. Aluminum electrolytic, ceramic, or tantalum capacitors are suggested. To en- sure proper EIA/TIA-562 signal levels over temperature when using 1pF capacitors, make sure the capacitance value does not degrade excessively as the temperature varies. If in doubt, use capacitors with a larger nominal value. Also observe the effective series resistance (ESR) value of the capacitors over temperature, since it will influence the amount of ripple on V+ and V-. To reduce the output impedance at V+ and V-, larger capacitors (up to 10uF) can be used. Driving Multiple Receivers Each transmitter is designed to drive a single receiver. Transmitters can be paralleled to drive multiple recievers. Transmitter Outputs when Exiting Shutdown The Typical Operating Characteristics section shows the reaction of the MAX560 transmitter outputs when exiting shutdown. Two transmitter outputs are shown going to opposite RS-232 levels as they become active (one transmitter is high, the other low). Each transmitter is loaded with 3kQ in parallel with 2500pF. The transmitter outputs display no ringing or undesirable transients as they come out of shutdown. MAX560 Receiver Operation in Shutdown During normal operation, the MAX560s receiver propagation delay is typically 1s. When entering shut- down with the receiver active, the receiver outputs R4 and R85 are not valid until 80,1s after SHDN is driven low. In shutdown mode, propagation delay increases to a typical 4us for a high to low transition and 6ys for a low to high transition (VCC = +3.3V), as shown in the Receiver Propagation Delay in Shutdown graph in the Typical Operating Characteristics. \rrespective of EN, receiver outputs R1, R2, and R3 are inactive in shutdown. When exiting shutdown, all receiver outputs are invalid until the charge pumps reach nominal levels (6004s when using 1uF capacitors). Power-Supply Decoupling In applications that are sensitive to power-supply noise, decouple Vcc to ground with a capacitor of the same value as the charge-pump capacitors. V+ and V- as Power Supplies A small amount of power can be drawn from V+ and V-, although this will reduce transmitter noise margins. See the Output Voltage vs. Load Current graph in the Typical Operating Characteristics section. High Data Rates The MAX560/MAX561 maintain the EIA/TIA-562 +3.7V minimum transmitter output voltage even at high data rates. The Typical Operating Characteristics show a transmitter output at 160kbits/sec. EIA/TIA Standards Before the MAX232 was invented, many "quasi" RS-232 interfaces were implemented with +5.0V power supplies. Output levels from the transmitters often failed to meet the RS-232 specifications, but the interfaces were func- tional over short distances, often at data rates above 20kbits/sec, due to the RS-232s 2V margin between its +5V minimum transmitter output specification and the +3V receiver input specification. The advent of +3V- powered systems led to the creation of the EIA/TIA-562 specification. Table 2 summarizes both specifications. Table 2. Summary of EIA/TIA-232E/V.28 and EIA/TIA-562 Specifications PARAMETER CONDITION TBPECIFICATION. SPECIFICATION Driver Output Voltage 0 Level 3kQ to 7kQ Load 5.0V to 15.0V 3.7V to 13.2V 1 Level -5.0V to -15.0V -3.7V to -13.2V Maximum Output Level No load +25V +13.2V Signal Rate (3kQ.< RL < 7kQ) CL = 2500pF Up to 20kbits/sec Up to 20kbits/sec CL = 1000pF Not defined Up to 64kbits/sec MIA KI/VI LOSXVW/O9SXUWMAXS60/MAX561 +3.3V Transceiver with Two EIA/TIA-562 Receivers Active in Shutdown Table 2. Summary of EIA/TIA-232E/V.28 and EIA/TIA-562 Specifications (continued) PARAMETER CONDITION SPECIFIGATION. SPECIFICATION Receiver Input Thresholds 0 Level 3.0V to 15.0V 3.0V to 15,0V 1 Level -3.0V to -15.0V -3.0V to -15.0V Maximum Input Level +25V +25V Maximum Instantaneous Slew Rate 30V/us 30V/prs Maximum Driver Output Short-Circuit Current 100mA 60mA Transition Rate on V.28 Ims or 3% of the period 4Vius Driver Output RS-232 4% of the period Driver Output Resistance with Power Off -2V < VOUT < 2V 3002 300Q Typical Operating Circuit Package Information 43.3 INPUT e- - maxi of 0 TP 560 oe +o Yo T+ tae WORN RDO Ag ga AR MAX561 C1 Ve lM cr. , 8avTossev YG 7a] C1 VOLTAGE DOUBLER co +f ces * fou uF oT C2. VOLTAGE DOUBLER eo fo , | #88 i ii HURPAROHWEARER 7 in [ a ny 43.3V; Mout be Vj - +4 400k } 2) 8 3 T2 my pn {LONI}. * CMOS 400k EIA/TIA-562 + i le 1 zer| INPUTS 2 OUTPUTS JL CL gaain T3IN 4 - T3QUT B A +3, 400k 2t 28 Tan [ T4out 8 9 Riout et Rin 5 L 4 INCHES [MILLIME R2aut [- Rin N_ | MAX [ MIN CMOS / Rggur 2 Raw EIA/TIA-562 OUTPUTS INPUTS 23 dour 2 I RAN 5k = 18 \ sour | - RSIN aE * _ 25 LER MAXI, EN EN) a! GND = (SHDN) SHDN 10 Maximn 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. 8 Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600 1992 Maxim Integrated Products Printed USA Maxim is a registered trademark of Maxim Integrated Products.