ADUM5401CRWZ Analog Devices Inc, ADUM5401CRWZ Datasheet - Page 18

• Manufacturer Part Number: ADUM5401CRWZ
• Description: IC,Digital Coupler,SOP,16PIN,PLASTIC
• Manufacturer: Analog Devices Inc
• Series: IsoPower®, iCoupler®r

Specifications of ADUM5401CRWZ

• Design Resources: Fully Isolated Input Module Based on AD7793 and ADuM5401(CN0066) Fully Isolated Input Module Based on AD7793, ADuM5401, and a High Performance In-Amp (CN0067)
• Inputs - Side 1/side 2: 3/1
• Number Of Channels: 4
• Isolation Rating: 2500Vrms
• Voltage - Supply: 3.3V, 5V
• Data Rate: 25Mbps
• Propagation Delay: 45ns
• Output Type: Logic
• Package / Case: 16-SOIC (0.300", 7.5mm Width)
• Operating Temperature: -40°C ~ 105°C
• Operating Temperature (min): -40C
• Operating Temperature Classification: Industrial
• Operating Temperature (max): 105C
• Package Type: SOIC W
• Rad Hardened: No
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: EVAL-ADUM540XEBZ - BOARD EVAL FOR ADUM540x
• Lead Free Status / Rohs Status: Compliant

ADuM5401/ADuM5402/ADuM5403/ADuM5404
THERMAL ANALYSIS
The ADuM5401/ADuM5402/ADuM5403/ADuM5404 parts
consist of four internal die attached to a split lead frame with
two die attach paddles. For the purposes of thermal analysis, the
die are treated as a thermal unit, with the highest junction tempera-
ture reflected in the θ
measurements taken with the parts mounted on a JEDEC standard,
4-layer board with fine width traces and still air. Under normal
operating conditions, the ADuM5401/ADuM5402/ADuM5403/
ADuM5404 devices operate at full load across the full temperature
range without derating the output current. However, following
the recommendations in the PCB Layout section decreases thermal
resistance to the PCB, allowing increased thermal margins in high
ambient temperatures.
EMI CONSIDERATIONS
The dc-to-dc converter section of the ADuM5401/ADuM5402/
ADuM5403/ADuM5404 components must operate at very high
frequency to allow efficient power transfer through the small
transformers. This creates high frequency currents that can
propagate in circuit board ground and power planes, causing edge
and dipole radiation. Grounded enclosures are recommended for
applications that use these devices. If grounded enclosures are not
possible, good RF design practices should be followed in the PCB
layout. Refer to the AN-0971 Application Note, Control of Radiated
Emissions for isoPower Devices, for the most current PCB layout
recommendations specifically for the ADuM5401/
ADuM5402/ADuM5403/ADuM5404.
PROPAGATION DELAY-RELATED PARAMETERS
Propagation delay is a parameter that describes the time it takes
a logic signal to propagate through a component (see Figure 24).
The propagation delay to a logic low output may differ from
the propagation delay to a logic high.
Pulse width distortion is the maximum difference between
these two propagation delay values and is an indication of how
accurately the input signal timing is preserved.
Channel-to-channel matching refers to the maximum amount
the propagation delay differs between channels within a single
ADuM5401/ADuM5402/ADuM5403/ADuM5404 component.
Propagation delay skew refers to the maximum amount the
propagation delay differs between multiple ADuM5401/
ADuM5402/ADuM5403/ADuM5404 components operating
under the same conditions.
INPUT (V
OUTPUT (V
Ix
)
Ox
)
Figure 24. Propagation Delay Parameters
JA
t
PLH
from Table 3. The value of θ
t
PHL
50%
50%
JA
is based on
Rev. A | Page 18 of 24
DC CORRECTNESS AND MAGNETIC FIELD IMMUNITY
Positive and negative logic transitions at the isolator input cause
narrow (~1 ns) pulses to be sent to the decoder via the transformer.
The decoder is bistable and is, therefore, either set or reset by
the pulses, indicating input logic transitions. In the absence of
logic transitions at the input for more than 1 μs, periodic sets of
refresh pulses indicative of the correct input state are sent to
ensure dc correctness at the output. If the decoder receives no
internal pulses of more than approximately 5 μs, the input side
is assumed to be unpowered or nonfunctional, in which case
the isolator output is forced to a default low state by the
watchdog timer circuit. This situation should occur in the
ADuM5401/ADuM5402/ADuM5403/ADuM5404 only during
power-up and power-down operations.
The limitation on the ADuM5401/ADuM5402/ADuM5403/
ADuM5404 magnetic field immunity is set by the condition
in which induced voltage in the transformer receiving coil is
sufficiently large to either falsely set or reset the decoder. The
following analysis defines the conditions under which this can occur.
The 3.3 V operating condition of the ADuM5401/ADuM5402/
ADuM5403/ADuM5404 is examined because it represents the
most susceptible mode of operation.
The pulses at the transformer output have an amplitude of >1.0 V.
The decoder has a sensing threshold of about 0.5 V, thus estab-
lishing a 0.5 V margin in which induced voltages can be tolerated.
The voltage induced across the receiving coil is given by
where:
β is magnetic flux density (Gauss).
r
N is the number of turns in the receiving coil.
Given the geometry of the receiving coil in the ADuM5401/
ADuM5402/ADuM5403/ADuM5404, and an imposed require-
ment that the induced voltage be, at most, 50% of the 0.5 V margin
at the decoder, a maximum allowable magnetic field is calculated
as shown in Figure 25.
n
is the radius of the n
V = (−dβ/dt)∑π r
0.001
0.01
Figure 25. Maximum Allowable External Magnetic Flux Density
100
0.1
10
1
1k
10k
MAGNETIC FIELD FREQUENCY (Hz)
n
2
th
; n = 1, 2, … , N
turn in the receiving coil (cm).
100k
1M
10M
100M