MCCS142233

MCCS142233 MOTOROLA | Alldatasheet

Document overview

• Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
• PDF pages: 10

Technical content

. . . 9-Bit Switchable SCSI Passive Bus Terminator (220 © and 330 Q) The MCCS142233 is a precision 9-bit switchable SCSI bus terminator with a Local-Vcc (LVCC) low voltage sense circuit to latch the Enable state. When the switch is enabled according to the truth table the device provides a 220 © resistance to Terminator Power (TERMPWR) and 330 Q resistance to Ground for SCSI termination of 9 bits. When the switch is disabled according to the truth table, the device is in a High Impedance State on all 9 bits. The low voltage sense circuit gives the device the ability to latch the current output state when power is removed from the LVcc pin When powering down a SCSI peripheral containing this device as long as Terminator Power remains there is no interruption to the SCS! bus. © 9 Switchable 220 0/330 Q Terminating Resistor Pairs © Resistor Ratio: R220/R330 = 220 0/330 Q + 2% © Operating Temperature Range: 0°C to 70°C * Local-Vcc (LVcc) Low Voltage Sense Circuit © Operating Voltage Range: 4.25 to 5.25 V * Active High or Active Low Enable Input * Resistor Tolerance + 7.5% (Over Temperature And Supply Voltage Ranges) Truth Table [test [Enode [Erase [ouput |] | Test [enews [Ena | Outut PIN ASSIGNMENT Veet 09 08 o7 06 7 18 7 16 15 14 pane [19 13[_ ] noc Wee [_]20 12[ | Test TERM. pwra L]* [7] enpa Enable [ ]2 10[ | Emode TERM- pwre [_|3 Kn) 4 5 6 7 8 | UU UU Uo | 01 02 03 04 05 ~ NOTE: All three TERMPWR pins must be connected externally. All three V@np pins must be connected externally. | (S) MOTOROLA @ } © MOTOROLA ING., 1991 f

TERMPWR © 120K82 rs Cas | Wee © q mi ONE OF NINE | 120KQ. | | Lj bk _ ao 3 | Com | Vret ' 40K22 | 3302 | _ | | Enable Latch Circuit ‘ Test O | ws Lp Emode O MAXIMUM RATINGS* [sympa [ Patera I * Maximum Ratings are those values beyond which damage to the device may occur. Functional operation should be restricted to the Recommended Operating Conditions. RECOMMENDED OPERATING CONDITIONS ee [inven [Oommen Serr [| a [kt [rosie ansFartne anmasonives) «dE | ef | [int [eae Fattine weg) [| ee MOTOROLA Mccs142233

Termpwr| 256 | o'Cto+ 700 Parameters ) [min [Max [Min [| Max | Condition Min High-Level Input Voltage 425 | 2.98 2.98 V_| Per Truth Table Vin (Emode & Test — HC Inputs) 5.25 3.68 3.68 Min High-Level Input Voltage 425 | 20 20 V_| Per Truth Table (Enable — HCT Input) 525 | 20 20 Max Low-Level Input Voltage 4.25 1.27 1.27 v Per Truth Table (Emode & Test — HC Inputs) 5.25 187 157 Vy i Max Low-Level Input Voltage 4.25 08 08 Vv Per Truth Table (Enable — HCT Inputs) 5.25 08 08 Vout Output Voltage 4.25 0.6 » TERMPWR #2°%. Vv | Vin= Vin or ViL When Terminated 5.25 HOUT! = 0 pA Max Input Leakage Current 5.25 40.10 +1.0 vA Vin = TERMPWR or GND (Emode & LV Inputs) Vref = TERMPWA, Max input Leakage Current 5.25 20.10 uA | Vin=TERMPWR (Enable Input) Max Input Leakage Current 5.25 20.10 10 | uA | Vin=GND (Test Input) Max Quiescent Supply Current 5.25 300 300 | wa | Emode/Ver/LVcc - TERMPWR (Enable Active Low) Enable/Test = GND lec Max Quiescent Supply Current 5.25 500 g00 | uA | Enable/lVgc = TERMPWR (Comparator Active) Emode/V;ef/Test = GND R220 Output Pull-Up Resistor Value 1 4.25 to 218 222 203 237 Enable/TesvLVcc = TERMPWR

5.25 Emode/Vreq/ = GND

R330 Output Pull-Down Resistor Value 1 4.25 to 327 333 305 355 Q TesvLV¢c = TERMPWR

5.25 Enable/Emode/Vref/ = GND

1 Resistor Values are compensated for a 30°C ambient to junction temperature delta. See “Thermal Considerations” section for a detailed explanation and formula. See Figures 3 & 4 for “Temperature Characteristics of Resistor Values’. TERMPWR Parameter ) Typical @ +25°C 425 3.50 VT- Max Latch Voltage (LVCc Input) 4.75 3.90 Vv Per Truth Table 5.25 4.25 4.25 4.00 vt+ Min Unlateh Voltage (LV Input) 475 4.40 7 Per Truth Table 5.25 4.75 Mccs142233 MOTOROLA

Figure 1. AC Characteristics Input Waveform Options

Figure 4. Temperature Characteristic of 330 © Resistor (1.3 watts) is dissipated. The following section details the device reliability as a function of junction temperature. when the ultimate in system reliability is required, thermal management must be considered as a prime system design goal. are consistent with system reliability goals. and continuous operating time to 0.1% wire bond failure, (1 failure per 1000 bonds).

Table |. Device Junction Temperature Vs. Time to 0.1% Bond Failures. ~ Junction Temperature Time Time °c (Hours) (Years) 80 1,032,200 117.8 90 419,300 47.9 100 178,700 20.4 110 79,600 9.4 120 37,000 42 130 17,800 2.0 140 8,900 1.0 MCCS142233 Applications Information Enable & Emode: The Enable and Emode input pins work together to determine the state of the termination resistors; either terminated(Enabled) or high impedance(Disabled). Enable and Emode allow the user to select the polarity of the enable signal to match the system logic signal used to drive the Enable input. {f Emode is tied “high” (to TERMPWR), the enable input becomes active “high”. Conversely, with Emode tied “low” (to GND), the Enable input becomes active low. This eliminates the need to add external inversion to the Enable signal regardless of the polarity of the system signal provided to the MCCS 142233. Emode can be used instead of Enable to select the state of the termination resistors. Emode has CMOS input levels, while Enable has TTL-compatible input levels UWcc & Vref: LVcc (Local-V¢c) and Vref pins provide a means for latching the proper termination state when the Enable input is driven by local logic. With Enable under local system logic control, the possibility exists for the peripheral containing the MCCS142233 to be powered down. The termination circuitry will still be powered from TERMPWR, but the Enable signal supplied to the chip by local logic will be lost. With the LV¢c¢ input tied to the peripheral’s internal power supply, the MCCS142233 will sense the loss of local power prior to loss of a valid Enable input signal, and will latch the Enable state which is present prior to local power loss The Vref pin is the analog ground for the Local-V¢c comparator and reference circuitry. For proper use of this feature, Vref must be tied to GND. Series resistance supplied by the user between Vyef and GND will alter the data sheet latch threshold of LVc¢c. Thus the LVcc threshold may be tailored to the user's specific requirements. Note: The input ESD structures on the Enable and LVcc inputs do not incorporate a diode to TERMPWR. Loss of TERMPWR will not result in the local power supply attempting to source TERMPWR to the system. Likewise, if the local supply (5.5 V maximum) exceeds TERMPWR (4.25 V minimum) current will not be drawn from the local power supply to TERMPWR through the MCCS142233. Use of the Local-Vcc sensing feature is only appropriate when the Enable inputis driven by system logic. If the MCCS 142233 is to be enabied using a wire jumper or throw switch, the user can disable the Local-V¢c sensing circuitry by hardwiring the LV¢c and Vref pins to TERMPWR. This will eliminate the power consumed by the comparator and reference circuitry to attain the lowest standby power condition possible. Test: The Test pin is used to open circuit one resistor branch of each terminator pair (“Test Mode’) to facilitate measurement of the resistor value in production. Itis held low internally through a pulldown resistor to operate the device in the “Active Mode" per the truth table. The Test mode may be of use in system debug once the MCCS142233is on the PC board. Itis recommended to leave the Test pin ~ either unconnected (pulled low internally) or grounded depending on whether the “Test Mode" offers any utility to the user in the system configuration MCCS142233 MOTOROLA

MCCS142233 Applications Information Enable Input Application Result A. No Connection to Enable Enable input will be pulled “high” internally. Termination state will depend upon the polarity of the Emode input. Emode should be hardwired “high” or the termination will be permanently disabled. B. Single Pole Switch to GND Enable input will be pulled “high” internally when the switch is open. Enable input will be held “low" when the switch is closed. Termination state will depend upon the polarity of the Emode input C. Double Pole Switch to Both This is a more expensive way to accomplish application B. above. It is more TERMPWR and GND economical to allow the internal pullup to provide the “high” input level D. Hardwired “High” With Emode also hardwired “high”, the MCCS 142233 will be permanently enabled and provide termination on all outputs. With Emode hardwired “low”, the chip will be permanently disabled. E. Hardwired “Low” With Emode also hardwired “low", the MCCS 142233 will be permanently enabled and provide termination on all outputs. With Emode hardwired “high” the chip will be permanently disabled. Application D. above is preferred over E. since D. does not draw current through the Enable input pull-up resistor. F. External Logic Driven With LVcc input connected to the local power supply and Vref connected to GND, the Local-Vcc sensing and Enable latching feature will be active. If this feature is not desired, hardwire LVCC and Vref to TERMPWR MCCS142233 MOTOROLA

oD | u [4] 0.18 (0.007) ® [tT] N©-PO© | LO-MS a) Er ro 4 yg" a 27 | ad Fko> Pe ——F Ce > v ion —@1 VIEW D-D [# [025 (0.010) © [T] NO-P© | LO-uO | fz I SECO a CATLIN NNCETONNIOEZON -—s—7 > co} 6 ¢ bs Y PM [ote (0.007) ® [7] NOP | LO-wd) | Ci — L" T 1S] 010/004) KI Ll LT iG >G J LTE SeATIN KS _ ST ORNTORZON DETAILS r of Lp E[ese0007 OT LOWS [NSPS [+ 0.25 (0.010) @ | T| L©-M© N©-PO | DETAIL S [om [ah ne an HWM MAR WAX [a —[- 970 1009 t oes [030s 0.365 |-0395 bearer one [oer] Pepa 29 Tom fore NoTes [033048 | 0013 | ocia | 1. DATUMS-L., 4, -N AND-P- DETERMINED. | @ | t27esc_[ 00508SC | WHERE TOP OF LEAD SHOULDER EXIT PLASTIC

0082 BODY AT MOLD PARTING LINE

Lost — Poot 2 ML TAUE POSTON TO BE MEASURED AT FR rer OH ae 4. DIVAN U0 NOTINGLUDE MOLD ee PROTAUSION ALLOWABLE HOLD PROTRUSION rere Ta0e Tee. Shei mo Ozman eh Of or ee |g COnTROWNG ONENSON-mo y a0 8 7760118 OBSOLETE NEW STANDARD 75.02 [erp a 3390 MOTOROLA MCCS142233

Motorola reserves the right to make changes without further notice to any products herein to improve reliability. function or design. Motorola does not assume ‘| any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the | rights of others. Motorola products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Motorola product could create a situation where | personal injury or death may occur. Should Buyer purchase or use Motorola products for any such unintended or unauthorized application, Buyer shall | indemnify and hold Motorola and its officers, employees. subsidiaries, affiliates, and distributors harmless against all claims, costs, damages. and expenses. and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use. ‘evenif such claim alleges that Motorola was negligent regarding the design or manufacture of the part. Motorola and (A are registered trademarks of Motorola, Ine. Motorola, Inc. is an Equal Opportunity/Affirmative Action Employer. ~ Literature Distribution Centers: USA: Motorola Literature Distribution; P.O. Box 20912; Phoenix, Arizona 85036, EUROPE: Motorola Ltd.; European Literature Center; 88 Tanners Drive, Blakelands, Milton Keynes, MK14 SBP, England JAPAN: Nippon Motorola Ltd.; 4-32-1, Nishi-Gotanda, Shinagawa-ku, Tokyo 141 Japan. ASIA-PACIFIC: Motorola Semiconductors H.K. Ltd.; Silicon Harbour Center, No. 2 Dai King Street, Tai Po Industrial Estate, Tai Po, N.T., Hong Kong. -ag yw oZ5637 - BR ( 0 0 MCCS142233