DC1746A-A Linear Technology, DC1746A-A Datasheet - Page 8

• Manufacturer Part Number: DC1746A-A
• Description: EVALUATION KIT LOW EMI LTM2881-3
• Manufacturer: Linear Technology
• Series: µModuler

Specifications of DC1746A-A

• Main Purpose: Interface, Transceiver RS-422/RS-485
• Embedded: No
• Utilized Ic / Part: LTM2881
• Primary Attributes: 3V Supply, Isolated, Transceiver + Power
• Kit Contents: Board, Datasheet
• Tool / Board Applications: Interface-Backplane, PCI, PCI Express, RS-XXX, Digital & Opto Isolator
• Mcu Supported Families: LTM2881
• Development Tool Type: Hardware - Eval/Demo Board
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• Secondary Attributes: -

LTM2881
PIN FUNCTIONS
LOGIC SIDE (V
D
output connected through isolation path to D
the condition of an isolation communication failure D
is in a high impedance state.
TE (Pin A2): Terminator Enable. A logic high enables a
termination resistor (typically 120Ω) between pins A
and B.
DI (Pin A3): Driver Input. If the driver outputs are enabled
(DE high), then a low on DI forces the driver noninverting
output (Y) low and the inverting output (Z) high. A high
on DI, with the driver outputs enabled, forces the driver
noninverting output (Y) high and inverting output (Z) low.
DE (Pin A4): Driver Enable. A logic low disables the driver
leaving the outputs Y and Z in a high impedance state. A
logic high enables the driver.
RE (Pin A5): Receiver Enable. A logic low enables the
receiver output. A logic high disables RO to a high imped-
ance state.
RO (Pin A6): Receiver Output. If the receiver output is
ena bled (RE low) and if A – B is > 200mV, RO is a logic
high, if A – B is < 200mV RO is a logic low. If the receiver
inputs are open, shorted, or terminated without a valid
signal, RO will be high. Under the condition of an isolation
communication failure RO is in a high impedance state.
V
pins RO, RE, TE, DI, DE, D
operating voltage is 1.62V to 5.5V. Internally bypassed
to GND with 2.2μF .
ON (Pin A8): Enable. Enables power and data communica-
tion through the isolation barrier. If ON is high the part is
enabled and power and communications are functional
to the isolated side. If ON is low the logic side is held in
reset and the isolated side is unpowered.
GND (Pins B1-B5): Circuit Ground.
V
ing voltage is 3V to 3.6V for LTM2881-3 and 4.5V to 5.5V
for LTM2881-5. Internally bypassed to GND with 2.2μF .
8
L
CC
OUT
(Pin A7): Logic Supply. Interface supply voltage for
(Pins B6-B8): Supply Voltage. Recommended operat-
(Pin A1): General Purpose Logic Output. Logic
CC
, V
L
, GND)
OUT
, and ON. Recommended
IN
. Under
OUT
ISOLATED SIDE (V
D
input on the isolated side relative to V
logic high on D
logic low on D
SLO (Pin L2): Driver Slew Rate Control. A low input, rela-
tive to GND2, will force the driver into a reduced slew rate
mode for reduced EMI. A high input, relative to GND2,
puts the driver into full speed mode to support maximum
data rates.
Y (Pin L3): Non Inverting Driver Output. High impedance
when the driver is disabled.
Z (Pin L4): Inverting Driver Output. High impedance when
the driver is disabled.
B (Pin L5): Inverting Receiver Input. Impedance is > 96kΩ
in receive mode with TE low or unpowered.
A (Pin L6): Non Inverting Receiver Input. Impedance is
> 96kΩ in receive mode with TE low or unpowered.
V
generated from V
regulated to 5V. Internally bypassed to GND2 with 2.2μF .
GND2 (Pins K1-K8): Isolated Side Circuit Ground. The
pads should be connected to the isolated ground and/or
cable shield.
CC2
IN
(Pin L1): General Purpose Isolated Logic Input. Logic
(Pins L7-L8): Isolated Supply Voltage. Internally
IN
IN
will generate a logic low on D
CC
will generate a logic high on D
CC2
by an isolated DC/DC converter and
, GND2)
CC2
and GND2. A
OUT
.
OUT
2881fb
. A