LOGIC DELAY LINES

SMFLDL-TTL-XX

Surface Mount FAST TTL Logic Delay Line

- T2L FAST input and output
- Delays stable and precise
- SO-14 pin pattern
- Wee DIP package (.235 high)
- Available in delays from 5 to 500ns
- Output isolated and with 10 T2L fan-out capacity
- Rise time 4ns maximum

DESIGN NOTES

The "Wee DIP Series" Logic Delay Lines developed by Engineered Components Company have been designed to provide precise delays with required driving and pick-off circuitry contained in a single SO-14 surface mount package compatible with FAST T²L circuits. These logic delay lines are of hybrid construction utilizing the proven technologies of active integrated circuitry and of passive networks utilizing capacitive, inductive and resistive elements. The MTBF on these modules, when calculated per MIL-HDBK-217 for a 50° C ground fixed environment, is in excess of 6 million hours. Module design includes compensation for propagation delays and incorporates internal termination at the output; no additional external components are needed to obtain the desired delay.

The SMFLDL-TTL is offered in 76 delays from 5 to 500ns. Delay tolerances are maintained as shown in the accompanying part number table, when tested under the "Test Conditions" shown. Delay time is measured at the +1.5V level on the leading edge. Rise time for all modules is 4ns maximum when measured from 0.75V to 2.4V. Temperature coefficient of delay is approximately +1200 ppm/°C over the operating temperature range of 0 to +70°C.

These modules accept either logic "1" or logic "0" inputs and reproduce the logic at the output without inversion. The delay modules are intended primarily for use with positive going pulses and are calibrated to the tolerances shown in the table on rising edge delay; where best accuracy is desired in applications using falling edge timing, it is recommended that a special unit be calibrated for the specific application. Each module has the capability of driving up to 10 T²L loads.

These "Wee DIP Series" modules are packaged in a SO-14 DIP housing, molded of flame-proof Diallyl Phthalate per ASTM D 5948, Type SDG-F, and are fully encapsulated in epoxy resin. Leads meet the solderability requirements of MIL-STD-202, Method 208. Leads provide positive standoff from the printed circuit board to permit solder-fillet formation and flush cleaning of solder-flux residues for improved reliability.

Marking consists of manufacturer's logo (EC²), part number, pin one (1) identification and date code of manufacture. All marking is applied by silk screen process using white epoxy paint in accordance with MIL-STD-130, to meet the permanency of identification required by MIL-STD-202, Method 215.

TEST CONDITIONS

1. All measurements are made at 25°C.
2. Vcc supply voltage is maintained at 5.0V DC.
3. All units are tested using a FAST toggle-type positive input pulse and one FAST T²L load at the output.
4. Input pulse width used is 100% longer than delay of module under test; spacing between pulses (falling edge to rising edge) is three times the pulse width used.

OPERATING SPECIFICATIONS

*Vcc supply voltage: ........... 4.75 to 5.25V DC 
Vcc supply current:
   Constant "0" in ............. 40mA typical
   Constant "1" in ............. 7mA typical 

Logic 1 Input:
   Voltage ..................... 2V min.; Vcc max.
   Current ..................... 2.7V = 20uA max.
                                 5.5V = 1mA max. 

Logic 0 Input:
   Voltage ..................... 0.8V max.
   Current ..................... -.6mA max. 

Logic 1 Voltage out: ........... 2.7V min.
Logic 0 Voltage out: ........... 0.5V max.
Operating temperature range: ... 0 to 70°C.
Storage temperature: ........... -55 to +125°C. 
                      

*Delays increase or decrease approximately 4% for a respective increase or decrease of 5% in supply voltage.

PART NUMBER TABLE

DELAYS AND TOLERANCES (in ns)

All modules can be operated with a minimum input pulse width of 100% of full delay and pulse period approaching square wave; since delay accuracies may be somewhat degraded, it is suggested that the module be evaluated under the intended specific operating conditions.

Special modules can be readily manufactured to improve accuracies and/or provide customer specified random delay times for specific applications.