Preliminary Technical Data

ADuM5000

Rev. PrA | Page 13 of 15

The ADuM5000 is protected against damage due to excessive

power dissipation by thermal overload protection circuits.

Thermal overload protection limits the junction temperature to

a maximum of 150°C (typical). Under extreme conditions (that

is, high ambient temperature and power dissipation) when the

junction temperature starts to rise above 150°C, the PWM is

turned off, reducing the output current to zero. When the

junction temperature drops below 130°C (typical), the PWM is

turned on again and output current is restored to its nominal

value.

occurs. At first, the ADuM5000 reaches its maximum current,

dissipated in the primary (see Error! Reference source not

found.

). If self-heating of the junction becomes great enough

to cause its temperature to rise above 150°C, thermal

shutdown activates, turning off the PWM and reducing the

output current to zero. As the junction temperature cools and

drops below 130°C, the PWM turns on and power is again

dissipated in the primary, again causing the junction

temperature to rise above 150°C. This thermal oscillation

between 130°C and 150°C causes a current oscillation that

continues as long as the short remains at the output.

Thermal limit protections are intended to protect the device

against accidental overload conditions. For reliable operation,

device power dissipation should be externally limited so

junction temperatures do not exceed 130°C.

POWER CONSIDERATIONS

The ADuM5000 Converter Primary side, is protected from

premature operation by Under Voltage Lock Out (UVLO)

circuitry. Below the minimum operating voltage, the power

converter holds its oscillator inactive.

INCREASING AVAILABLE POWER

The ADuM5000 devices are designed with capability of running

in combination with other compatible isoPower devices. The

a master. It can also receive a PWM signal from another device

slave device. When the ADuM5000 is acting as a slave, its

power is regulated by the master device allowing multiple

isoPower parts to be combined in parallel while sharing the

load equally. When the ADuM5000 is configured as a

Master/Stand alone unit, it generates its own PWM feedback

signal to regulate itself and slave devices.

The ADuM5000 can act as a master or a slave deice, the

ADuM5400 can only be a master/stand alone, and the

ADuM5200 can only be a slave/Stand alone device. This means

that the ADuM5000, ADuM5200, and ADuM5400 can only be

used in certain master slave combinations as listed in Table 13.

Slave

ADuM5000

ADuM5200

ADuM5400

ADuM5000

Y

Y

N

ADuM5200

N

N

N

Master

ADuM5400

Y

Y

N

Table 13 Allowed combinations of isoPower Parts

The allowed combinations of master and slave configured parts

listed in Table 13 is sufficient to make any combination of

power and channel count. Table 14 illustrates how isoPower

devices can provide many combinations of data channel count

and multiples of the single unit power.

Number of Data Channels

0

2

4

6

ADuM5000

Master

ADuM520x

Master

ADuM540x

Master

ADuM540x

Master

ADuM12xx

1 Unit

Power

ADuM5000

Master

ADuM500x

Master

ADuM540x

Master

ADuM540x

Master

ADuM5000

Slave

ADuM5200

Slave

ADuM5200

Slave

ADuM520x

Slave

2 Unit

Power

ADuM5000

Master

ADuM5000

Master

ADuM540x

Master

ADuM540x

Master

ADuM5000

Slave

ADuM5000

Slave

ADuM5000

Slave

ADuM520x

Slave

3 Unit

Power

ADuM5000

Slave

ADuM520x

Slave

ADuM5000

Slave

ADuM5000

Slave

Table 14 Configurations for Power and Data Channels

INSULATION LIFETIME

All insulation structures will eventually break down when

subjected to voltage stress over a sufficiently long period. The

rate of insulation degradation is dependant on the

characteristics of the voltage waveform applied across the

insulation. In addition to the testing performed by the

regulatory agencies, Analog Devices carries out an extensive set

of evaluations to determine the lifetime of the insulation

structure within the ADuM5000.

ADI performs accelerated life testing using voltage levels higher

than the rated continuous working voltage. Acceleration factors

for several operating conditions are determined. These factors

allow calculation of the time to failure at the actual working

voltage. The values shown in Table 10 summarize the peak

voltage for 50 years of service life for a bipolar ac operating

condition, and the maximum CSA/VDE approved working

voltages. In many cases, the approved working voltage is higher

than 50-year service life voltage. Operation at these high

working voltages can lead to shortened insulation life in some

cases.

The insulation lifetime of the ADuM5000 depends on the