CS3511-CNZ Cirrus Logic Inc, CS3511-CNZ Datasheet - Page 24

• Manufacturer Part Number: CS3511-CNZ
• Description: Audio Amplifiers IC 2X10W Digital Audio Amp
• Manufacturer: Cirrus Logic Inc

Specifications of CS3511-CNZ

• Product: Class-D
• Output Power: 11.8 W
• Available Set Gain: 27.3 dB
• Common Mode Rejection Ratio (min): 55 dB
• Thd Plus Noise: 0.025 %, 0.019 %
• Operating Supply Voltage: 12 V
• Supply Current: 38 mA
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Audio Load Resistance: 8 Ohms
• Input Signal Type: Differential, Single
• Minimum Operating Temperature: - 10 C
• Output Signal Type: Differential
• Supply Type: Single
• Supply Voltage (max): 13.5 V
• Supply Voltage (min): 8.5 V
• Output Type: 2-Channel Stereo
• Package / Case: QFN-32
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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9. THERMAL CHARACTERISTICS
9.1
Junction to Case Thermal Impedance
Thermal Flag
This device is designed to have the metal flag on the bottom of the device soldered directly to a metal plane
on the PCB. To enhance the thermal dissipation capabilities of the system, this metal plane should be cou-
pled with vias to a large metal plane on the backside (and inner ground layer, if applicable) of the PCB.
In either case, it is beneficial to use copper fill in any unused regions inside the PCB layout, especially those
immediately surrounding the CS3511. In addition to improving in electrical performance, this practice also
aids in heat dissipation.
The heat dissipation capability required of the metal plane for a given output power can be calculated as
follows:
θ
where,
θ
T
T
P
θ
CA
CA
JC
J(MAX)
A
D
= Ambient temperature in °C
= RMS power dissipation of the device, equal to 0.176*P
= Junction-to-case thermal resistance of the device in °C/Watt, equal to 1 °C/Watt
= [(T
= Thermal resistance of the metal plane in °C/Watt
= Maximum rated operating junction temperature in °C, equal to 150 °C
J(MAX)
- T
Parameter
A
) / P
D
] - θ
JC
Symbol
RMS-OUT
θ
JC
(assuming 85% efficiency)
Min
-
Typ
1
Max
-
CS3511
DS845F1
°C/Watt
Units