AD5770R datasheet(34/59 Pages) AD

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AD5770R

Data Sheet

Rev. 0 | Page 34 of 59

Because the AD5770R can dissipate a large amount of power, it is

recommended to provide some heat sinking capability to allow

power to dissipate easily.

For the WLCSP package, heat is transferred through the solder

balls to the PCB board. θJA thermal impedance is dependent on

board construction. More copper layers enable heat to be

removed more effectively.

If using an external RSET resistor, the low side of the RSET resistor

must be connected to REFGND before the connection to

AGND. Ensure that the width of the trace connecting RSET to

the IREF pin is as wide as possible to reduce the resistance and

the temperature coefficient of the trace.

Table 11. Thermal Considerations for 49-Ball WLCSP Package

Parameter

Description

Maximum Power Dissipation

Maximum allowed AD5770R power dissipation (PDISS) when operating at an ambient temperature of 105°C,

150 105 1.5 W

JMAX

−

Maximum Ambient

Temperature

Maximum allowed ambient temperature, when dissipating 1.985 W across the AD5770R:

TJMAX – PDISS × θJA = 150 – (1.985 × 30) = 90.45°C

Power dissipation calculation example:

AVDD = DVDD = IOVDD = 3.3 V, PVDDx = 2.9 V

AVEE = PVEE0 = 0 V, RLOAD = 5 Ω per channel, AD5770R quiescent power dissipation = 110 mW

IDAC0 = 300 mA, power dissipation = 420 mW

IDAC1 = 250 mA, power dissipation = 412.5 mW

IDAC2 = 150 mA, power dissipation = 322.5 mW

IDAC3, IDAC4, IDAC5 = 100 mA, power dissipation = 720 mW

Total power dissipation = 110 mW + 1.875 W = 1.985 W

AD5770R Datasheet(PDF) 34 Page - Analog Devices