CAT5251YI-00 ON Semiconductor, CAT5251YI-00 Datasheet - Page 2

• Manufacturer Part Number: CAT5251YI-00
• Manufacturer: ON Semiconductor

Specifications of CAT5251YI-00

• Number Of Elements: 4
• # Of Taps: 256
• Resistance (max): 100KOhm
• Power Supply Requirement: Single
• Interface Type: Serial (SPI)
• Single Supply Voltage (typ): 3.3/5V
• Dual Supply Voltage (typ): Not RequiredV
• Single Supply Voltage (min): 2.5V
• Single Supply Voltage (max): 6V
• Dual Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 24
• Package Type: TSSOP
• Lead Free Status / Rohs Status: Compliant

CAT5251
PIN DESCRIPTION
SI: Serial Input
SI is the serial data input pin. This pin is used to
input all opcodes, byte addresses and data to be
written to the CAT5251. Input data is latched on the
rising edge of the serial clock.
SO: Serial Output
SO is the serial data output pin. This pin is used to
transfer data out of the CAT5251. During a read
cycle, data is shifted out on the falling edge of the
serial clock.
SCK: Serial Clock
SCK is the serial clock pin. This pin is used to
synchronize
microcontroller and the CAT5251. Opcodes, byte
addresses or data present on the SI pin are latched
on the rising edge of the SCK. Data on the SO pin is
updated on the falling edge of the SCK.
A0, A1: Device Address Inputs
These
addressing multiple devices. A total of four devices
can be addressed on a single bus. A match in the
slave address must be made with the address input
in order to initiate communication with the CAT5251.
R
The four sets of R
terminal connections on a mechanical potentiometer.
R
The four R
of a mechanical potentiometer.
¯¯¯ : Chip Select
¯¯¯ is the Chip select pin. CS
CAT5251 and CS
high takes the SO output pin to high impedance and
forces the devices into a Standby mode (unless an
internal write operation is underway). The CAT5251
draws ZERO current in the Standby mode. A high to
low transition on CS
sequence being initiated. A low to high transition on
¯¯¯ after a valid write sequence is what initiates an
internal write cycle.
¯¯¯ : Write Protect
WP
¯¯¯ is the Write Protect pin. The Write Protect pin
WP
will allow normal read/write operations when held
high. When WP
operations to the Data registers are inhibited
(change of wiper control register is allowed). WP
going low while CS
Doc. No. MD-2017 Rev. H
CS
CS
CS
H
W
, R
: Wiper
L
: Resistor End Points
inputs
W
pins are equivalent to the wiper terminal
¯¯¯ is tied low, all non-volatile write
the
¯¯¯ high disables the CAT5251. CS
¯¯¯ is still low will interrupt a write to
set
H
and R
¯¯¯ is required prior to any
communication
the
L
pins are equivalent to the
device
¯¯¯ low enables the
address
between
when
¯¯¯
¯¯¯
the
2
the registers. If the internal write cycle has already
been initiated, WP
any write operation.
HOLD
The HOLD
CAT5251 while in the middle of a serial sequence
without having to re-transmit entire sequence at a
later time. To pause, HOLD
while SCK is low. The SO pin is in a high impedance
state during the time the part is paused, and
transitions on the SI pins will be ignored. To resume
communication, HOLD
low. (HOLD
function is not being used.) HOLD
directly to V
¯¯¯¯¯ : Hold
PIN DESCRIPTION
Pin #
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
1
2
3
4
5
6
7
8
9
¯¯¯¯¯ pin is used to pause transmission to the
¯¯¯¯¯ should be held high any time this
HOLD
¯¯¯¯¯
Name
GND
SCK
R
R
¯¯¯
¯¯¯
R
R
R
V
R
WP
R
R
SO
R
NC
R
R
NC
R
CS
A0
A1
SI
CC
W3
CC
W0
W1
W2
H3
H0
H1
H2
L3
L0
L1
L2
or tied to V
¯¯¯ going low will have no effect on
¯¯¯¯¯ is brought high, while SCK is
Function
Serial Data Output
Device Address, LSB
Wiper Terminal for Potentiometer 3
High Reference Terminal for
Potentiometer 3
Low Reference Terminal for
Potentiometer 3
No Connect
Supply Voltage
Low Reference Terminal for
Potentiometer 0
High Reference Terminal for
Potentiometer 0
Wiper Terminal for Potentiometer 0
Chip Select
Write Protection
Serial Input
Device Address
Low Reference Terminal for
Potentiometer 1
High Reference Terminal for
Potentiometer 1
Wiper Terminal for Potentiometer 1
Ground
No Connect
Wiper Terminal for Potentiometer 2
High Reference Terminal for
Potentiometer 2
Low Reference Terminal for
Potentiometer 2
Bus Serial Clock
Hold
¯¯¯¯¯ must be brought low
Characteristics subject to change without notice
CC
through a resistor.
¯¯¯¯¯ may be tied high
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