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dc1562bfa
DEMO MANUAL DC1562B
Description
LTC699X-X
TimerBlox: Oscillators, One Shots,
PWM, Delay, Power on Reset
Demonstration circuit 1562B is an engineering tool to
design and evaluate the LTC699X-X family of TimerBlox
®
circuits. The center section of the board contains a pre-
configured TimerBlox function. DC1562B comes in twelve
timing function variations as outlined in Table 1.
Surrounding the center board is a playground prototyping
area. The prototyping area has pads for DIP-8, S8, MS8,
or S6 packages with bread boarding connections to each
pin and two convenient power buses and ground bus
surrounding the entire area. This area is for conditioning
signals to control the timer function and for adding loads
controlled in time.
L, LT, LTC, LTM, Linear Technology, TimerBlox and the Linear logo are registered trademarks
of Linear Technology Corporation. All other trademarks are the property of their respective
owners.
Using the Demo BoarD
The center part of the board can be detached as a stream-
lined circuit, to combine with a pre-existing circuit. For
application
flexibility, a provision is made for buffering and
inverting the output of the timer. An optional NC7W04P6X
SC70 package dual inverter can be added at U2 to provide
this functionality.
Design files for this circuit board are available at
http://www.linear.com/demo
To understand the simplicity and flexibility of the TimerBlox
function, download the appropriate data sheet from the LT C
website, www.linear.com. Each evaluation board comes
with a TimerBlox part, decoupling cap and a bulk decou
-
pling 10µF tantalum
cap. Resistors are also installed that
configure the TimerBlox device so that they are ready to use
by simply adding power. Changing the default configura
-
tion of the demo board is a simple matter of determining
a few new resistor values. Simply select a pair of resistor
values for the DIV value from the data sheet DIV table,
calculate the value of R
SET
required, replace the resistor
on the board, apply power, and go! Single supply power
between 2.25V and 5.5V and ground must be supplied
directly
to the center board.
The outer prototyping section of the board can be used
with single or dual supplies as required. When using the
prototyping area, the outermost trace, which is ground,
must be connected (hand wired) to the ground on the
center board section. All input and output holes are sized
for 65mil turret terminals, or wires can be soldered in the
holes directly.
Changing the timer configuration requires changing re
-
sistor values on the center board. The resistor lead holes
can
accept “pressed-in” DIP sockets, or resistors can
be soldered directly in the holes. Pads for 0805 surface
mount resistors are also included at each position where
a leaded resistor could be used. Pads are also included
for three 25-turn trim pots which can be used to replace
R
SET
(R8) for master oscillator frequency adjustment, PSF
in (R10) for voltage controlled options, and R
DEV
(R7) for
frequency divider control to permit real-time adjustments
while running.
