ADUM5401CRWZ Analog Devices Inc, ADUM5401CRWZ Datasheet - Page 17

• 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

APPLICATIONS INFORMATION
The dc-to-dc converter section of the ADuM5401/ADuM5402/
ADuM5403/ADuM5404 works on principles that are common
to most modern power supplies. It is a secondary side controller
architecture with isolated pulse-width modulation (PWM)
feedback. V
switches current into a chip-scale air core transformer. Power
transferred to the secondary side is rectified and regulated to
either 3.3 V or 5 V. The secondary (V
the output by creating a PWM control signal that is sent to the
primary (V
PWM modulates the oscillator circuit to control the power being
sent to the secondary side. Feedback allows for significantly
higher power and efficiency.
The ADuM5401/ADuM5402/ADuM5403/ADuM5404 provide a
regulation control output (RC
to other isoPower devices. This feature allows a single regulator
to control multiple power modules without contention. When
auxiliary power modules are present, the V
connected together to work as a single supply. Because there
is only one feedback control path, the supplies work together
seamlessly.
The ADuM5401/ADuM5402/ADuM5403/ADuM5404 implement
undervoltage lockout (UVLO) with hysteresis on the V
input. This feature ensures that the converter does not go into
oscillation due to noisy input power or slow power-on ramp rates.
A minimum load current of 10 mA is recommended to ensure
optimum load regulation. Smaller loads can generate excess noise
on chip due to short or erratic PWM pulses. Excess noise generated
this way can cause data corruption, in some circumstances.
PCB LAYOUT
The ADuM5401/ADuM5402/ADuM5403/ADuM5404 digital
isolators with 0.5 W isoPower integrated dc-to-dc converters
require no external interface circuitry for the logic interfaces.
Power supply bypassing is required at the input and output
supply pins (see Figure 23). Note that a low ESR bypass capacitor
is required between Pin 1 and Pin 2, as close to the chip pads
as possible.
The power supply section of the ADuM5401/ADuM5402/
ADuM5403/ADuM5404 uses a 180 MHz oscillator frequency
to efficiently pass power through its chip-scale transformers. In
addition, normal operation of the data section of the iCoupler
introduces switching transients on the power supply pins. Bypass
capacitors are required for several operating frequencies. Noise
suppression requires a low inductance, high frequency capacitor;
ripple suppression and proper regulation require a large value
capacitor. These are most conveniently connected between
Pin 1 and Pin 2 for V
DD1
DD1
) side by a dedicated iCoupler data channel. The
power is supplied to an oscillating circuit that
DD1
and between Pin 15 and Pin 16 for V
OUT
) signal that can be connected
ISO
) side controller regulates
ISO
pins can be
DD1
power
ISO
Rev. A | Page 17 of 24
.
ADuM5401/ADuM5402/ADuM5403/ADuM5404
To suppress noise and reduce ripple, a parallel combination of at
least two capacitors is required. The recommended capacitor
values are 0.1 μF and 10 μF for V
have a low ESR; for example, use of a ceramic capacitor is
advised.
Note that the total lead length between the ends of the low ESR
capacitor and the input power supply pin must not exceed 2 mm.
Installing the bypass capacitor with traces more than 2 mm in
length may result in data corruption. A bypass capacitor between
Pin 1 and Pin 8 and between Pin 9 and Pin 16 should also be
considered unless both common ground pins are connected
together close to the package.
In applications involving high common-mode transients, take
care to ensure that board coupling across the isolation barrier is
minimized. Furthermore, the board layout should be designed
such that any coupling that does occur equally affects all pins
on a given component side. Failure to ensure this can cause
voltage differentials between pins, exceeding the Absolute
Maximum Ratings specified in Table 8, thereby leading to latch-
up and/or permanent damage.
The ADuM5401/ADuM5402/ADuM5403/ADuM5404 are power
devices that dissipate about 1 W of power when fully loaded and
running at maximum speed. Because it is not possible to apply
a heat sink to an isolation device, the devices primarily depend
on heat dissipation into the PCB through the GND pins. If the
devices are used at high ambient temperatures, care should be
taken to provide a thermal path from the GND pins to the PCB
ground plane. The board layout in Figure 23 shows enlarged pads
for Pin 8 and Pin 9. Implement large diameter vias from the pads
to the ground and power planes. This reduces inductance and
noise generation.
Multiple vias in the thermal pads can significantly reduce
temperatures inside the chip. The dimensions of the expanded
pads are left to the discretion of the designer and the available
board space.
V
V
V
V
BYPASS < 2mm
RC
IA
IB
IC
ID
GND
GND
V
/V
/V
/V
/V
DD1
OUT
OA
OB
OC
OD
1
1
Figure 23. Recommended PCB Layout
DD1
. The smaller capacitor must
V
GND
V
V
V
V
V
GND
ISO
OA
OB
OC
OD
SEL
/V
/V
/V
/V
ISO
ISO
IA
IB
IC
ID