3D7608 & 3D7612
8-BIT & 12-BIT PROGRAMMABLE
PULSE GENERATORS
(
SERIES 3D7608 & 3D7612: PARALLEL INTERFACE
)
FEATURES
•
•
•
•
•
•
•
•
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All-silicon, low-power CMOS technology
TTL/CMOS compatible inputs and outputs
Vapor phase, IR and wave solderable
Programmable via latched parallel interface
Increment range:
0.25ns through 800us
Pulse width tolerance:
1% (See Table 1)
Supply current:
8mA typical
Temperature stability:
±1.5%
max (-40C to 85C)
Vdd stability:
±0.5%
max (4.75V to 5.25V)
TRIG
RES
P0
P2
P4
P6
NC
GND
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
data
3
delay
devices,
inc.
VDD
OUT
OUTB
P1
P3
P5
P7
AE
TRIG
RES
P0
P2
P4
P6
P8
NC
P10
GND
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
PACKAGES / PINOUTS
VDD
OUT
OUTB
P1
P3
P5
P7
P9
AE
P11
3D7608R-xx SOIC
3D7612W-xx SOL
For mechanical dimensions, click
here.
For package marking details, click
here.
FUNCTIONAL DESCRIPTION
The 3D7608 & 3D7612 devices are versatile 8- & 12-bit
programmable monolithic pulse generators. A rising-edge on the
trigger input (TRIG) initiates the pulse, which is presented on the
output pins (OUT,OUTB). The pulse width, programmed via the
serial interface, can be varied over 255 (3D7608) or 4095
(3D7612) equal steps according to the formula:
t
PW
= t
inh
+ addr * t
inc
where addr is the programmed address, t
inc
is the pulse width
increment (equal to the device dash number), and t
inh
is the
inherent (address zero) pulse width. The device also offers a reset
input (RES), which can be used to terminate the pulse before the
programmed time has expired.
PIN DESCRIPTIONS
TRIG
RES
OUT
OUTB
Trigger Input
Reset Input
Pulse Output
Complementary
Pulse Output
AE
Address Enable Input
P0-P11 Address Inputs
VDD +5 Volts
GND Ground
NC
Do not connect externally
The all-CMOS 3D7608 & 3D7612 integrated circuits have been designed as reliable, economic alternatives
to hybrid TTL pulse generators. The 3D7608 is offered in a standard 16-pin SOIC, and the 3D7612 is
offered in a standard 20-pin SOL.
TABLE 1: PART NUMBER SPECIFICATIONS
PART #
(8-BIT)
3D7608R-0.25
3D7608R-0.5
3D7608R-1
3D7608R-2
3D7608R-5
3D7608R-10
3D7608R-20
3D7608R-50
3D7608R-100
3D7608R-200
3D7608R-500
3D7608R-1K
3D7608R-2K
3D7608R-5K
3D7608R-10K
3D7608R-20K
3D7608R-50K
PART #
(12-BIT)
3D7612W-0.25
3D7612W-0.5
3D7612W-1
3D7612W-2
3D7612W-5
3D7612W-10
3D7612W-20
3D7612W-50
3D7612W-100
3D7612W-200
3D7612W-500
3D7612W-1K
3D7612W-2K
3D7612W-5K
3D7612W-10K
3D7612W-20K
3D7612W-50K
Pulse Width
Increment
0.25ns
±
0.12ns
0.50ns
±
0.25ns
1.0ns
±
0.5ns
2.0ns
±
1.0ns
5.0ns
±
2.5ns
10ns
±
5.0ns
20ns
±
10ns
50ns
±
25ns
100ns
±
50ns
200ns
±
100ns
500ns
±
250ns
1.0us
±
0.5us
2.0us
±
1.0us
5.0us
±
2.5us
10us
±
5.0us
20us
±
10us
50us
±
25us
Maximum
P.W. (8-Bit)
73.25ns
±
3ns
137.5ns
±
3ns
265ns
±
3ns
520ns
±
6ns
1.28us
±
13ns
2.56us
±
26ns
5.11us
±
52ns
12.8us
±
128ns
25.5us
±
255ns
51.0us
±
510ns
128us
±
1.3us
255us
±
2.6us
510us
±
5.2us
1.28ms
±
13us
2.55ms
±
26us
5.10ms
±
52us
12.8ms
±
128us
Maximum
P.W. (12-Bit)
1.03us
±
10ns
2.05us
±
21ns
4.10us
±
41ns
8.19us
±
82ns
20.5us
±
205ns
41.0us
±
410ns
81.9us
±
819ns
205us
±
2.1us
410us
±
4.1us
819us
±
8.2us
2.05ms
±
21us
4.10ms
±
41us
8.19ms
±
82us
20.5ms
±
205us
41.0ms
±
410us
81.9ms
±
819us
205ms
±
2.1 ms
PART #
(8-BIT)
3D7608R-100K
3D7608R-200K
3D7608R-500K
3D7608R-800K
Pulse Width
Increment
100us
±
50us
200us
±
100us
500us
±
250us
800us
±
400us
Maximum
P.W. (8-Bit)
25.5ms
±
260us
51.0ms
±
510us
128ms
±
1.3ms
204ms
±
2.1ms
NOTE: Any increment between 0.25ns
and 800us (50us for the 12-bit generator)
not shown is also available as a standard
device.
2006
Data Delay Devices
Doc #06009
5/8/2006
DATA DELAY DEVICES, INC.
3 Mt. Prospect Ave. Clifton, NJ 07013
1
3D7608 & 3D7612
APPLICATION NOTES
GENERAL INFORMATION
Figure 1 illustrates the main functional blocks of
the 3D7608 & 3D7612. Since these devices are
CMOS designs, all unused input pins must be
returned to well-defined logic levels, VDD or
Ground.
The pulse generator architecture is comprised of
a number of delay cells (for fine control) and an
oscillator & counter (for coarse control). Each
device is individually trimmed for maximum
accuracy and linearity throughout the address
range. The change in pulse width from one
address setting to the next is called the
increment,
or LSB. It is nominally equal to the
device dash number. The minimum pulse width,
achieved by setting the address to zero, is called
the
inherent pulse width.
For best performance, it is essential that the
power supply pin be adequately bypassed and
filtered. In addition, the power bus should be of
as low an impedance construction as possible.
Power planes are preferred. Also, signal traces
should be kept as short as possible.
error is less than 1.0 LSB at every address (see
Table 1).
The
absolute error
is defined as follows:
e
abs
= t
PW
– (t
inh
+ addr * t
inc
)
where t
inh
is the nominal inherent delay. The
absolute error is limited to 1.5 LSB or 3.0 ns,
whichever is greater, at every address.
The
inherent pulse width error
is the deviation of
the inherent width from its nominal value. It is
limited to 2.0 ns from the nominal inherent pulse
width of 10 ns.
PULSE WIDTH STABILITY
The characteristics of CMOS integrated circuits
are strongly dependent on power supply and
temperature. The 3D7608 & 3D7612 utilize novel
compensation circuitry to minimize the
performance variations induced by fluctuations in
power supply and/or temperature.
With regard to stability, the output pulse width of
the 3D7608 & 3D7612 at a given address, addr,
can be split into two components: the
inherent
pulse width
(t
inh
) and the
relative pulse width
(t
PW
- t
inh
). These components exhibit very different
stability coefficients, both of which must be
considered in very critical applications.
The thermal coefficient of the relative pulse width
is limited to
±250
PPM/C, which is equivalent to a
variation, over the -40C to 85C operating range,
of
±1.5%
from the room-temperature pulse width.
This holds for all dash numbers. The thermal
coefficient of the inherent pulse width is
nominally +10ps/C for dash numbers less than 1,
and +15ps/C for all other dash numbers.
The power supply sensitivity of the relative pulse
width is
±0.5%
over the 4.75V to 5.25V operating
range, with respect to the pulse width at the
nominal 5.0V power supply. This holds for all
dash numbers. The sensitivity of the inherent
pulse width is nominally –1ps/mV for all dash
numbers.
It should also be noted that the DNL is also
adversely affected by thermal and supply
variations, particularly at the MSL/LSB
crossovers (ie, 63 to 64, 127 to 128, etc).
PULSE WIDTH ACCURACY
There are a number of ways of characterizing the
pulse width accuracy of a programmable pulse
generator. The first is the
differential nonlinearity
(DNL), also referred to as the increment error. It
is defined as the deviation of the increment at a
given address from its nominal value. For most
dash numbers, the DNL is within 0.5 LSB at
every address (see Table 1: Pulse Width Step).
The
integrated nonlinearity
(INL) is determined
by first constructing the least-squares best fit
straight line through the pulse-width-versus-
address data. The INL is then the deviation of a
given width from this line. For all dash numbers,
the INL is within 1.0 LSB at every address.
The
relative error
is defined as follows:
e
rel
= (t
PW
– t
inh
) – addr * t
inc
where addr is the address, t
PW
is the measured
width at this address, t
inh
is the measured
inherent width, and t
inc
is the nominal increment.
It is very similar to the INL, but simpler to
calculate. For most dash numbers, the relative
Doc #06009
5/8/2006
DATA DELAY DEVICES, INC.
Tel: 973-773-2299
Fax: 973-773-9672
http://www.datadelay.com
2
3D7608 & 3D7612
APPLICATION NOTES (CONT’D)
TRIGGER & RESET TIMING
Figure 2 shows the timing diagram of the device
when the reset input (RES) is not used. In this
case, the pulse is triggered by the rising edge of
the TRIG signal and ends at a time determined
by the address loaded into the device. While the
pulse is active, any additional triggers occurring
are ignored. Once the pulse has ended, and after
a short recovery time, the next trigger is
recognized. Figure 3 shows the timing for the
case where a reset is issued before the pulse
has ended. Again, there is a short recovery time
required before the next trigger can occur.
ADDRESS UPDATE
The 3D7608/3D7612 can operate in one of two
addressing modes. In the transparent mode (AE
held high), the parallel address inputs must
persist for the duration of the output pulse, in
accordance with Figure 4. In the latched mode,
the address data is stored internally, which
allows the parallel inputs to be connected to a
multi-purpose data bus. Timing for this mode is
also shown in Figure 4.
TRIGGER TRG
RESET RES
INPUT
LOGIC
DELAY
LINE
OSCILLATOR/
COUNTER
OUTPUT
LOGIC
OUT
OUTB
PULSE OUT
BIT-SHIFT LOGIC
ADDR ENABLE AE
8- OR 12-BIT LATCH
P0
P1
P7 P8
P9
P10
P11
Figure 1: Functional block diagram
t
TW
TRIG
t
ID
OUT
OUTB
t
PW
t
RTO
Figure 2: Timing Diagram (RES=0)
t
TW
TRIG
t
RW
RES
t
RTR
t
ID
OUT
OUTB
t
RD
Figure 3: Timing Diagram (with reset)
Doc #06009
5/8/2006
DATA DELAY DEVICES, INC.
3 Mt. Prospect Ave. Clifton, NJ 07013
3
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