
DUAL, HCMOS-INTERFACED
FIXED DELAY LINE 
(SERIES MDU28C)
delay 
devices, inc.
FEATURES PACKAGES
I1
• Two independent delay lines
• Fits standard 8-pin DIP socket
• Low profile
• Auto-insertable
N/C
GND
1 
2
I2
3 
4
• Input & outputs fully CMOS interfaced & buffered
• 10 T2L fan-out capability
MDU28C-xx DIP 
MDU28C-xxA1 Gull-Wing 
MDU28C-xxB1 J-Lead 
MDU28C-xxM Military DIP
FUNCTIONAL DESCRIPTION
The MDU28C-series device is a 2-in-1 digitally buffered delay line. The 
signal inputs (I1-I2) are reproduced at the outputs (O1-O2), shifted in time 
by an amount determined by the device dash number (See Table). The 
delay lines function completely independently of each other.
VDD
8
O1
7
N/C
6
O2
5
N/C 
N/C 
N/C
N/C
GND
PIN DESCRIPTIONS
I1-I2 Signal Inputs 
O1-O2 Signal Outputs 
VDD +5 Volts 
GND Ground
2
13
3
12
4
11
5
I2
Military SMD 
MDU28C-xxMD1 
MDU28C-xxMD4
10
6
9
7
8
N/C 
O1 
N/C 
N/C 
N/C 
O2
SERIES SPECIFICATIONS
• Minimum input pulse width: 100% of total delay
• Output rise time: 8ns typical
• Supply voltage: 5VDC ± 5%
• Supply current: I 
  I
 = 40µa typical
CCL
 = 45ma typical
CCH
• Operating temperature: 0° to 70° C
• Temp. coefficient of total delay: 300 PPM/°C
O2O1
100%
100%
VDD GNDI1 I2
Functional block diagram
DASH NUMBER SPECIFICATIONS
Part
Number
MDU28C-10 
MDU28C-12 
MDU28C-16 
MDU28C-20 
MDU28C-25 
MDU28C-30 
MDU28C-35 
MDU28C-40 
MDU28C-45 
MDU28C-50 
MDU28C-60 
MDU28C-75 
MDU28C-100
NOTE: Any dash number between 10 and 100
not shown is also available.
Delay Per
Line (ns)
10 ± 2.0 
12 ± 2.0 
16 ± 2.0 
20 ± 2.0 
25 ± 2.0 
30 ± 2.0 
35 ± 2.0 
40 ± 2.0 
45 ± 2.2 
50 ± 2.5 
60 ± 3.0 
75 ± 3.7
100 ± 5.0
1997 Data Delay Devices
Doc #97040 DATA DELAY DEVICES, INC. 1
12/12/97 3 Mt. Prospect Ave. Clifton, NJ 07013
 

APPLICATION NOTES
HIGH FREQUENCY RESPONSE
The MDU28C tolerances are guaranteed for 
input pulse widths and periods greater than those 
specified in the test conditions. Although the 
device will function properly for pulse widths as 
small as 100% of the total delay and periods as 
small as 200% of the total delay (for a symmetric 
input), the delays may deviate from their values 
at low frequency. However, for a given input 
condition, the deviation will be repeatable from 
pulse to pulse. Contact technical support at Data
DEVICE SPECIFICATIONS
TABLE 1: ABSOLUTE MAXIMUM RATINGS
PARAMETER SYMBOL MIN MAX UNITS NOTES
DC Supply Voltage V 
Input Pin Voltage V 
Storage Temperature T 
Lead Temperature T
DD
IN 
STRG 
LEAD
Delay Devices if your application requires device 
testing at a specific input condition.
POWER SUPPLY BYPASSING
The MDU28C relies on a stable power supply to 
produce repeatable delays within the stated 
tolerances. A 0.1uf capacitor from VDD to GND, 
located as close as possible to the VDD pin, is 
recommended. A wide VDD trace and a clean 
ground plane should be used.
-0.3 7.0 V
-0.3 VDD+0.3 V
-55 150 C 
300 C 10 sec
TABLE 2: DC ELECTRICAL CHARACTERISTICS
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
High Level Output Voltage V 
Low Level Output Voltage V 
High Level Output Current I
Low Level Output Current I 
High Level Input Voltage V 
Low Level Input Voltage V 
Input Current I
(0C to 70C, 4.75V to 5.25V)
OH
OL
OH 
OL
IH 
IL
IH
3.98 4.4 V VDD = 5.0, IOH = MAX
0.15 0.26 V VDD = 5.0, IOL = MAX
3.15 V
-4.0 mA
4.0 mA
1.35 V
0.10
µA
VIH = MIN, VIL = MAX 
VIH = MIN, VIL = MAX
VDD = 5.0
Doc #97040 DATA DELAY DEVICES, INC. 2
12/12/97 Tel: 973-773-2299   Fax: 973-773-9672   http://www.datadelay.com
 

MDU28C-xx (Commercial DIP)
1 2 3 4
MDU28C-xxM (Military DIP)
.018 
TYP.
.300±.010
3 Equal spaces
each .100±.010
Non-Accumulative
PACKAGE DIMENSIONS
5678
Lead Material: 
Nickel-Iron alloy 42
.290 
MAX.
TIN PLATE
.010±.002
.280 
MAX.
.350 
MAX.
1 2 3 4
.300 
TYP.
5678
.440 
MAX.
.290
.020
MAX.
TYP.
.180
TYP.
.020 
TYP.
.010 TYP.
.300 
TYP.
.020 
TYP.
1 2 3 4
.040 
TYP.
5678
.270 
TYP.
.300 
MAX.
.430 
TYP.
.050
TYP.
MDU28C-xxA1 (Commercial Gull-Wing)
1
.300 
TYP.
7 8
.200 MAX. (Com) 
.225 MAX. (Mil)
14
.510 
MAX.
.020 
TYP.
1 2 3 4
5678
.040 
TYP.
.270 
TYP.
.350 
MAX.
.320 
TYP.
.110
TYP.
MDU28C-xxB1 (Commercial J-Lead)
1
.300 
TYP.
7 8
.200 MAX. (Com) 
.225 MAX. (Mil)
14
.510 
MAX.
.065
TYP.
MDU28C-xxD1 (Commercial SMD) 
MDU28C-xxMD1 (Military SMD)
Doc #97040 DATA DELAY DEVICES, INC. 3
12/12/97 3 Mt. Prospect Ave. Clifton, NJ 07013
.360
TYP.
.065
TYP.
MDU28C-xxD4 (Commercial SMD) 
MDU28C-xxMD4 (Military SMD)
 

DELAY LINE AUTOMATED TESTING
TEST CONDITIONS
INPUT: OUTPUT: 
Ambient Temperature: 25oC ± 3oC Load: 1 FAST-TTL Gate 
Supply Voltage (VDD): 5.0V ± 0.1V C 
Input Pulse: High = 5.0V ± 0.1V Threshold: 2.5V (Rising & Falling)
Low = 0.0V ± 0.1V
Source Impedance: 50Ω Max. 
Rise/Fall Time: 5.0 ns Max. (measured
between 0.5V and 4.5V )
Pulse Width: PWIN = 1.5 x Total Delay 
Period: PERIN = 10 x Total Delay
NOTE: The above conditions are for test only and do not in any way restrict the operation of the device.
COMPUTER
SYSTEM
: 5pf ± 10%
load
PULSE
GENERATOR
INPUT 
SIGNAL
OUTPUT 
SIGNAL
T
RISE
T
RISE
PW
V
IN
IH
DEVICE UNDER
TEST (DUT)
Test Setup
PER
IN
V
OH
T
FALL
T
FALL
TIME INTERVAL
COUNTER
V
IL
V
OL
Timing Diagram For Testing
Doc #97040 DATA DELAY DEVICES, INC. 4
12/12/97 Tel: 973-773-2299   Fax: 973-773-9672   http://www.datadelay.com