Moteur de recherche de fiches techniques de composants électroniques
  French  ▼

Delete All
ON OFF
ALLDATASHEET.FR

X  

Preview PDF Download HTML

SMP9517 Fiches technique(PDF) 3 Page - Summit Microelectronics, Inc.

No de pièce SMP9517
Description  Nonvolatile DACPOT™ Electronic Potentiometer With Debounced Push Button Interface
Download  8 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Fabricant  SUMMIT [Summit Microelectronics, Inc.]
Site Internet  http://www.summitmicro.com
Logo SUMMIT - Summit Microelectronics, Inc.

SMP9517 Fiches technique(HTML) 3 Page - Summit Microelectronics, Inc.

  SMP9517 Datasheet HTML 1Page - Summit Microelectronics, Inc. SMP9517 Datasheet HTML 2Page - Summit Microelectronics, Inc. SMP9517 Datasheet HTML 3Page - Summit Microelectronics, Inc. SMP9517 Datasheet HTML 4Page - Summit Microelectronics, Inc. SMP9517 Datasheet HTML 5Page - Summit Microelectronics, Inc. SMP9517 Datasheet HTML 6Page - Summit Microelectronics, Inc. SMP9517 Datasheet HTML 7Page - Summit Microelectronics, Inc. SMP9517 Datasheet HTML 8Page - Summit Microelectronics, Inc.  
Zoom Inzoom in Zoom Outzoom out
 3 / 8 page
background image
SMP9517
3
SUMMIT MICROELECTRONICS, Inc.
2035 3.0 5/10/00
There are five main blocks to the SMP9517: an 7-bit
EEPROM memory; input debounce circuits, control logic,
and 7-bit counter; 7-bit data register; decode section and
resistor ladder (DAC); and the buffer amplifier.
The input control section operates just like an up/down
counter. The output of this counter is fed to the data
register and then decoded to activate one of 127 electronic
switches connected to the resistor ladder. The ladder is
comprised of 128 resistors of equal value connected in
series. At the bottom of the ladder and at the junctions of
the resistors there are electronic switches that transfer the
voltage at each point to the buffer amplifier and then to the
output.
The SMP9517 is designed to interface directly to two
pushbutton switches that effectively move the potentiom-
eter wiper up or down. The UP# and DWN# inputs,
respectively, increment or decrement the 7-bit counter.
The data input to the DAC is decoded to select one of the
128 wiper positions along the resistive ladder. The wiper
increment input UP# and the wiper decrement input
DWN# are connected to internal pull-ups so that they
normally remain high. When pulled low by an external
pushbutton switch or a logic low level input, the wiper will
be switched to the next adjacent tap position. Internal
debounce circuitry prevents inadvertent switching of the
wiper position if UP# or DWN# remain low for less than
30ms (typical).
Each of the buttons can be pushed either once for a single
increment/decrement or held low continuously for multiple
increments/decrements. The number of increments/dec-
rements of the wiper position depends on how long the
button is pushed. When making a continuous push, after
the first second, the increment/decrement speed in-
creases. For the first second the device will be in the slow
scan mode. Then, if the button is held for longer than one
second, the device will go into the fast scan mode. As soon
as the button is released the SMP9517 will return to a
standby condition.
The DAC, whether set to 00HEX or FFHEX, acts like its
mechanical equivalent and does not move beyond the last
position. That is, the counter does not wrap around when
clocked up to FFHEX or down to 00HEX.
AUTOSTORE
The value of the counter is stored in EEPROM memory
whenever the chip senses a power-down of VDD while
STR# is enabled (held low). When power is restored the
contents of the memory are recalled and the counter reset
to the last value stored. If AUTOSTORE is to be imple-
mented, STR# is typically hard wired to GND. If STR# is
held high during power-up and then taken low the wiper will
not respond to the UP# or DWN# inputs until STR# is
brought high and the store is complete. See Figure 1.
Manual (Pushbutton) Store
When STR# is not enabled (held high) a pushbutton switch
may be used to pull STR# low and released to perform a
manual store of the wiper position in EEPROM memory.
See Figure 2.
Effect of VDD Removal
The resistor ladder, connected between VH and VL, does
not change value when VDD is removed. However, the
buffer amplifier no longer functions, and consequently a
high impedance appears at the VOUT pin.
Figure 2: Typical circuit with STR store pin
controlled by push button switch
Figure 1: Typical circuit with STR store pin used in
AUTOSTORE mode
DEVICE OPERATION
UP#
DWN#
VH
GND
VDD
STR#
VL
VOUT
8
7
6
5
1
2
3
4
VDD
3.3µF
2035 T Fig01 3.0
UP#
DWN#
VH
GND
VDD
STR#
VL
VOUT
8
7
6
5
1
2
3
4
VDD
20k
2035 T Fig02 3.0


Html Pages

1  2  3  4  5  6  7  8 


Fiches technique Télécharger

Go To PDF Page


Lien URL




Politique de confidentialité
ALLDATASHEET.FR
ALLDATASHEET vous a-t-il été utile ?  [ DONATE ] 

À propos de Alldatasheet   |   Publicité   |   Contactez-nous   |   Politique de confidentialité   |   Echange de liens   |   Fabricants
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn