MAAIM CMOS RF/Video Multiplexers General Description Features Maxim's MAX310 and MAX311 are CMOS monolithic @ -76dB Typical Off Isolation at SMHz analog multiplexer/demultiplexers designed for use a 1 with signal frequencies ranging from DC through @ ~634B Typical All Channel Off" Isolation at SMHz video. The MAX310 is a 1-of-8 multiplexer while the # Phase Shift Match Between Channels, <1 MAX311 is for 2-of-8 (4 channel differential) at SMHz applications. @ Break-Before-Make Switching A key feature of the MAX310/311 is extremely high off isolation at high frequencies. The isolation of + Since sens Range, +4.5V to +16.5 and each off channel to the output is guaranteed to be g PRY -66dE at 5MHz. The input signal range is +12V to @ Symmetrical, Bi-directlonal Operation -15V with 415V power suppliss while power can- 7 sumption is typically 1.1mW. # Latch-Up Proof Construction All control inputs are fully compatible with TTL and Ordering Information GMOS logic. Decoding is in standard BCD format and an Enable input is also provided to simplity cascading of devices. The MAX310 and MAX311 will | _- PART TEMP, RANGE PACKAGE operate with nearly any power supply combination MAX310C/D @Cia- 70C Dice which totals less than 36V (Vt - V-) including single : : : : Cto -70C 16 Lead Plastic DIP supply operation at +12V, +15V, and +28V with V- MAXSTOCRE OCto ~70C _16 Lead Massie connected to GND. MAX3IOCWN OCto-70'C 18 Lead Wide SO . . MAX310E PE 40Cto +85C 16 Lead Plastic DIP Applications MAXS10EWN 40Cto 85C 18 Lead Wide SO Video Switching and Crosspoint Systems MAXGIOEJE a0-Cto 86 16 Lead CERDIP Automatic Test Equipment MAX31OMJE 55' Cte +125C 16 Lead GERDIP Medical Ultrasound Phased Array Systems MAX311C.D ocin-70C Dice Data Logging of High Frequency Signals MAXS11 CPE OGto -7O';C 16 Lead Plastic DIP Digital Signal Processing MAX311C0WN Cto+70C 18 Lead Wide 50 MAX311 EPE -40Cto +B5"C 16 Lead Plastic DIP Pin Configuration MAX3T1EWN 40Cto - 85C 18 Lead Wide SO MAX311 EJE =40Cto 186C 16 Lead CERDIP Top View MAXS1IMJE 5SClo +128C 16 Lead GERDIP | st] ~ fa ~ oe 1 Operating C a ig] GND 8) 1] 13) GND COT pica rating Circuit 8, [2] fel Ay = 8; 2] iz] Ay P g _ 8, Cy #VLAKIZA [14] A, Sy By lL AX) el Tf | A, 8] MAXIIO Ta] Ap 34] MAXGI0 5] Ay 5, LE] mz] EN 868s CE] 14] EW 5, GE] mvt SLE [ia] y+ 7] i) duT 8+] nz] OUT $4 [Z Pav Sa LE ir] v- co 2 NvC ce it NC (Z| axa put | Ga] MAX310 CHANAELS i od VT 5 8 [T) OUT, Si, ia] OUT, cH 84 LE Pia] GND 8.4 CZ] Fr] Ho q $4] axe [a] A, Soy GB] 4x8 Ty A &y Co] MARSH = Tia] ap Sy LE MAXGIt [i] Ag Sip EJ PZ]EN Sie CE ri] EW Sa Ce ij ve Sue i] fia] We so SE AH Ours 8 7] riz] DUT, 4g LE OV- 84, CE] pir) - i wit DS AD NC No Insertion Loss, 8 Channel Mux I i _ SV AALS Mexim Integrated Praducis 1 maxim 13 a registered trademark of Maxim Integrated Products. EEE/OLEXVNMAX310/311 CMOS RF/ Video Multiplexers ABSOLUTE MAXIMUM RATINGS Valtage referenced to V- yt GND .......... Digital Inputs Input Current Sand COMMON OUT 0... cece cece cee cee eee es =50mA All pins except S and COM. OUT oo... . eee eee =30mA Lead Temperature ...0.. 2. cee eee ee eee +300C Storage Temperature ..2..-.. ceca e ee eee -65C to +150C Operating Temperature Range MAX3100, MAXS11C 22.22.02 0C to +70C MAXSIOE. MAXSI1E .........0.2.. 00-2 e ee 40C ta 185C MAXSIOM, MAX3STIM oo... ee eee eee -65C ta +125C Power Dissipation (16-Pin packages) CERDIP tderate 10mW/C above +75C) .....0.. 75amw Plastic DIP (derate 7.35mW/C above +75C) ....,.., s50mWw Smatl Gutline (derate IMW/PS above +76C) ........ S50mWw Stresses listed under Absojute Maximum Ratings may be appiled fone at a timal to devices without resulting in permanent damage. These are stress ratings only, and functional operation of the device at these or any other canditions above those indicated in the operational sections of the specifications is not implied. Exposure /o sbsolute maximum ratings canditions for extended peciads may affect device reliability. ELECTRICAL CHARACTERISTICS (Over Temperature V7 = +15V, V~ = -15V, GND = OV unless otherwise indicated) PARAMETER SYMBOL | CONDITIONS MIN. TYP. MAX. | UNITS : Vt Vo = +18V -15 +e Analog Signal Range vilye 2 s5y 5 + Vin = +54, lout = 10mA Channel ON Resistance Ron Ta, = +25C 150 250 fi Over Temp. 300 ON Resistance Match aRon Vin = 25, ipyr = 10mA 6 % Figure 10, Ts = +26C 0.4 10 OFF Input Leakage Current ISIOFFI Over Temp 3 100 na Figure 11, Ta = +25C 0.8 10 er tet nt IpyoFF) MAX310 Over Temp. 20 100 nA g MAX311 Over Temp. 10 50 Figure 12, Ta = +26C 1 10 Cae vent Iban MAX310 Over Temp. 30 200 na g MAX311 Over Temp. 16 100 Inout Law Threshold Va Vio = +18V, +5V 0.8 Input High Threshold Vax VT/No = 4+15, 45 24 Input Current (Logic) Ia Va = OV or SV +10 aA : Figure 7; Ta = +25C 0.6 15 Access Time tace: Over Temp. 2.0 us Figure 8; Ta = +25C 0.3 to. | Enable Delay ON or OFF tewoworr | 9 Over Temp. 20 Fe Break-Before-Make Delay ton-tore Figure 9 30 100 ng OFF Isoiation, Single -T, = _ - Channal to OUT 1SOsc Figure 3; Ta = +26C 66 76 dB . Figure 4, 5, T, = +25C cree aT ISOne MUX Disabled, EN = +D.8V -63 dB MUX Enabled, EN = +2.4 -5B Adjacent Channel Crosstalk ISOy Figure 6, Ta = +25C -72 dB Channel Input Capacitance Ta = +25C, Vin = 10mVans 10 MHz OFF State OsioFF) 5 pF ON State Cs on: 45 Channel Output Capacitance Ta = +25C; OFF State Cororr) EN = +0.8, MAX310 38 | MAX311 20 : pF ON State Cororry EN =+2.4, MAX310 57 MAX311 40 Gharge Injaction Q Figure 13, Ta = +25C 110 po Supoly Current; t I* _ 75 200 yr {- EN, AG, Al, A2 = GV or +5V 0.4 100 aA Supply Voltage Range Ta = +25C +4.5 =16.5 Vv 2 MIAXIS/VICMOS RF/Video Multiplexers Detailed Description e OUT DECODE LOGIC AND LEVEL TAANSLATOAS - Gno it J] | Ap Ar Az EN MAX3IT Sin ee Sen 71 Su T 4 a | a Sap a 11 pana San + UT, J} DECODE LOGIC AND LEVEL TAANSLATOAS yt - GND Mo OAL EW Figure? Functional Alock Diagrams The Maxim MAX310 and MAX311 contain 9 video switches combined with an address decoder and level translators (Figure 1). Each of the B video switches consists of 3 N-channel FETs configured as shown in Figure 2. This T configuration provides the high frequency OFF isolation required when switching wide-band video, audio, or digital signals. N-channel FETs are used in the MAX310/311's T switches because of their low capacitance and con- sequently superior isclation characteristics. A side effect is that the N-channel ON resistance varies somewhat with the voltage difference between the analog input signal and V+. This effect is shown in the Typical Operating Characteristics section. Wy {| 7 L060 +f>>- at Figure 2. N-channel T Switen Channel selection is performed by applying a binary input to the address inputs Ap, A, and As {Ag and Ay only for MAX311). The address decoder selects chan- nels as shown in the truth tables (Table 1}. All digital inputs are compatible with TTL and CMOS logic levels. Break-before-make switch timing is guaranteed for both multiplexers. This prevents momentary short- ing of inputs when changing multiplexer channels. MMAXI FI The MAX310 and MAX211 are also fully bilateral and so can be used backwards, as demultiplexers, with no loss in performance. Specifically, one input signal can be routed to one of several outputs. TABLE 1. CHANNEL SELECTION INPUT CODES [MAXI MAGQH A, A, Ag EN ONChannel | A, A, EN ON Channel 9 0 D1 1 o 0 1 1A+4B 0 g 4 1 2 0 1 1 2A+ 2B o 1 oo 41 3 1 0 1 3A + 3B o 171 4 4 | 4A+4B 1 0 0 1 5 X X 0 ALLOFF 19074 1 6 1 1 Oo 1 7 1 1 1 1 8 x xX & OQ ALLOFF Application Hints Maximizing Isolation With all high frequency circuits, careful printed cir- cuit board layout is essential for optimum perform- ance. To maintain the high frequency isolation of the MAX310/311, signal paths should be of minimum length and ground piane should be used where pos- sible, including between adjacent input pins. A ground or power supply trace between adjacent inputs will markedly improve isolation between channels. Both Vt and V- should be bypassed to ground with O.1uF ceramic capacitors. The leads of the capaci- tors should be kept as short as possible to minimize LEE/OLEXVINMAX310/311 CMOS RF/Video Multiplexers series inductance. The bypass capacitors should also be located as physically close to the multiplexer as possible. input Capacitance The capacitance of an input channel changes from about 5pF in the OFF state to around 45pF when ON. To minimize bandwidth reduction due to input capacitance, the inputs should be driven from a low impedance source. A 752 source impedance results in a 3dB frequency response of 47MHz when loaded with 45pF, Charge injection With +15V supplies, injected charge from the inter- nal switch drive circuitry te the analog signal path is typically 110 picocoulombs. As shown in the Typical Characteristics graph, charge injection is relatively independent of the analog signal voltage. Insertion Loss With +15 supplies and +2 video signals, the 1209. typical ON resistance of the MAX310/311 results in -8.3dB insertion loss when used with a 750 output load. This insertion loss is virtually constant fram DG to over 20MHz. TABLE 2. PHASE SHIFT AT 10MHz INFUT CHANNEL OUTPUT - INPUT PHASE SHIFT MAX311 Ry = 10k0 A, = 750) Sy -22 -12 Se -21 -11.5 Ss -20 -11.5 Ss -20 -11.2 Ss -20 -11.2 55 -20.5" -11.4 S; -20.7 -11.5 5e ~20.48 ~11.5 Test Conditians ve = +18V, V7 = -TSV Vin = 1-25Veus at TOMHz, OFF inputs terminated with 7S{b Operation with Power Supplies Gther Than +15V Table 3 shows how different power supply voltages affect the MAX310/311's analog signal range and channel ON resistance (Ron). This data is also shown graphically in the Typical Operating Charac- teristics section. Since N-channel FETs are used in the switches, Ron is determined by the voltage difter- ence between Vt and the input voltage. For lowest Ron, use a negative power supply (V-} equal to the most negative input voltage, and a positive power supply (V+) 30V above the negative supply. For example, if only positive signals need to be switched, use OV for V- and +30V for Vt to achieve minimum Ron. This also reduces ON resistance variation with analog signai level and input voltage dependent changes in insertion loss, which minimizes differen- tial gain errors. The digital input thresholds are nearly independent of V+, remaining near +1.4V over the entire operating supply voltage range of +4.5V to +18V (9V to 36V single supply). The MAX310/311 switching delay times vary some- what with power supply voltage. Access time (see Figure 2) increases fram typically 600ns with +15V supplies to 3us with 5V supplies. Other switching times are also proportionately longer with +5V power supplies. Propagation Delay and Phase Shift In Table 2, the typical phase shift for each channel is shown. Note that both the phase shift and the phase shift difference between channels are reduced with a 750 output load. At 1OMHz, the channel-to-channel match is better than 1 with a 750 load and improves as the frequency is reduced. Phase shift measurements for the MAX311 are sim- ilar to those in Table 2. The data for the MAX310 channels 1 ta 4 corresponds to MAX311 channels 1A to 44, Channels 5 to 8 correspond te MAX311 chan- nels 1B to 4B. TABLE 3. SIGNAL RANGE AND Ron vs SUPPLY VOLTAGE SUPPLY VOLTAGE SIGNAL RANGE TYPICAL Ron AT Vin - vr NEGATIVE POSITIVE -15 +15V -15 to +12 104.0) at -10 2651] at +10V -5V to +45V 1150) at -5V 1500 at +5V GND -15 OV to +42 1201) at OV 1500) at +5V GND +30V OV to +27V 90Nn. at OV 1001 at +5V -5V +B -8V to +2 240! at -2V 480M at +2V -10 +10V -10 to +7V 1400 at -5V 220M at +5V -5V +15 -5V to +12V 1158 at -5Y 1500) at +5V MA AALSCMOS RF/Video Multiplexers OFF Isolation Measurements Figure 3 is used to test and specify the MAX310/311's single channel OFF isolation. in the case illustrated, channel S; has signal applied while all other inputs are grounded through 75M except for the ON chan- nel (Se in Figure 3). This is shorted directly to ground to prevent pickup from external wiring. Each channel meets this test to an isolation limit of -66dB at 5MHz. re uh GND = co & Ag = = INPUT CODE $4 Al F-* 7 WHICH TURAS $2 ON S4 AIAX LS fo [- s MAX310 in p< av ET yt - vi 37 OUT = & - -15 . 750 ALL 75n a Ost Circuit shown for 5, isolation with $2 ON. The ON channel is shorted to GND, Other channels are measured in a similar fashion. Figure 3. Singia Channel OFF Isolatian ((SOg) Tast Cireuit Figure 4 shows the test circuit for OFF isolation with all channels driven. The impedance of the source connected to the selected channel (in this case, Sa} significantly affects feedthrough. With a 752) source impedance the typical measured OFF isalation is -58dB at 5MHz. This increases to -63dB if the source impedance is reduced to 1011 or less, OFF isolation also increases with decreasing frequency. For exam- ple, when the frequency is reduced from 10MHz to 1MHz the isolation improvement is typically -20dB. Figure 5 shows a similar circuit far testing ail-channel isolation with the multiplexer disabled (EN law). 1 640 -_ 32 Ap 7 A2Vams SMH? Tose 3a Al as ary g, MAXIE 4) MAXKIIG = 8a EN f-} Se yt ooo OF 8 i Se v- noe st OleF x Lt Figure 4. All Channel OFF isolation (1304) Teast Circuit (MUX Disabled) P= ---y+ Sy GND f-- 52 Ag }= INPUT COOE 83 Ay ft p> OWHICH TURNS 34 ONT" - Sa APLAR Ap - They ss MAX370 gy b-a aay = Ly we [-- ot Sr OUT = One iB > Vout By \- vi To LiVams hy Qlut 5MHz TL Grounding ON channel improves isolation by -50B. Other channais are measured in a similar fashion. Figure . Aff Channel! OFF fsolation (/SO,c) Tast Cireurt (MUX Enabied)} RON vs. SUPPLY VOLTAGE AND CHARGE INJECTION vs. Typical Operating Characteristics OFF ISOLATION INPUT VOLTAGE ANALOG INPUT VOLTAGE ys, FREQUENCY 500 130 au 1 +28C V> - +54 4057 __- = -5V T= 25C a0 400 120 a 5 : = =z & a m0 a0 = FIGURE 3 A z = z : = S = FIGUAE 4 2 3 a 4 8 0p 2 at FIGURE 5 = 190 90 a 0 0 80 0 15 -I0 -5 o +5 +1000 +15 i 5 o +5 +10 o1 1 10 100 Vi Wl ANALOB INPUT [] FREQUENCY (MHz) fVIAXL/I bLE/OLEXVANMAX3 10/311 CMOS RF/Video Multiplexers oT vr a 6ND -_ 82 4) / hi hy wwPuT CoE 5, HIAKIM 4, Wes MAXSIG as EN een dy = yor 3 out x Ola 8a Ye tT -1V , = OlpF IN ISO, =20LO0G = = ViorVe Figure & Adjacent Channel Crosstalk (S0%) Tast Circus | -W 4 cx] -_ | Az 7 HW | 4 Al fo ow TIL IN | 1] 5, KIA ALS Ay : MAX3i0 i 455 KO tea ss vt -- +150 j O lar s our =" ay ] Sr i -1ay Mur | TK | an QF ta is defined as the longest of ta; and ta:. | = - L Figure ? Access Time (ta) Tast Circuit, 1 8) ND -_ Az S45 A +030 Sq WIAXIZK fy MAX3I0 ad 5 mh ow TTLIN FL wy an | ss ve -15Ir . da aur RG Tt x on i nae lk tenon e] |e tenures it Daf a = Figure 8. Enabla Delay (tex; on,orr)) Tast Circuit. ten can/oFFy i8 defined as the longest of +S5V and -5 input case. Vl AXAL/VICMOS RF/ Video Multiplexers i 3 eo -}-_ & Le = a 4: Al Ww TTLIN 4 sexe Ag _] 3 MAX210 tN ] 4s ee 3: ouT Bs We ur =4aV wed | TTL we a | LL {ow-{nFe* | IV LV tow torr is defined as the shortest of +5V and -5 input case Figure 9. Break-Before-Make Dalay (toy-toge} Test Citcuit. '3\0FF] _ -5 (71}__ 84 cha -}_ -1 &2 Ag = INPUT CODE +5 By Al ;-a) WHICK TURNS $i OFF" e-fag PLAX LE gp Le MAXG1O Ss EN Puro dy 8a oe -15V Ole + .-| 8; aut -} open 1 L__] 5 v na -15V ~ 0. uF "Shown for S; Other channels are measured in a similar fashion, W 64) -oL J 8 fy Pe INPUT COOE = &: Ay -~+ WHICH TURNS 31 Oh* Sy MIA Ac ;+ Be MAX3I0 ie Paez ay 3 - + NW 1" . VoqoNi ue T % DUT + 2bY ] ve Fe -15V aL Oak L * shown for Sj. Other channels are measurad in a similar fashion. Figure 10. OFF Input Leakage Currant Test Circuit, Figure 72. ON Output Leakage Current Tast Circuit. J4 Ga -_ 82 Ag $, 7VIAMLML Ay L MARIO & EN 5B ve i bY = 8 aut io Si ~~ 5a ro loqaeF) OD. LaF L Thee & 640 -}_ & Az }~ INPUT CODE Ss Ai -~ } FOREACH CHANKEL 34 *WIAXIHL ag La MAX310 +oV 3 mn} _| Loo So ye - FV 8 a Your Sa ue -taW 1O00pF rT iu QO =Ci(4Vout} dH Figure 17. OFF Output Loakage Current Test Circuit. SVLAALSEI Figure 13. Charga Injection (Q) Test Circuit LEE/OLEXVIN