LM48520TLBD National Semiconductor, LM48520TLBD Datasheet - Page 14

• Manufacturer Part Number: LM48520TLBD
• Description: BOARD EVALUATION FOR LM48520TL
• Manufacturer: National Semiconductor
• Series: Boomer®r

Specifications of LM48520TLBD

• Amplifier Type: Class D
• Output Type: 2-Channel (Stereo)
• Max Output Power X Channels @ Load: 1.3W x 2 @ 8 Ohm
• Voltage - Supply: 2.4 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Board Type: Fully Populated
• Utilized Ic / Part: LM48520
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

www.national.com
Output Speaker Protection Function
The LM48520’s output voltage limiter can be used to set a
minimum and maximum output voltage swing magnitude. The
voltage applied to the VLimit pin controls the limit on the out-
put voltage level. The output level is determined by the fol-
lowing equation:
or
Where, Vout clipped = the desired output level measured in
Vpk, PV1 = Boost output voltage, and Vlimit is the voltage
applied the the Vlimit pin on the LM48520.
To disable the limiter, set Vlimit = 0V.
Figure 2 provides an example of how the output voltage limiter
functions with V
R
L
= 8Ω, V
Vout clipped = 1/2 * (PV1 — 3/8 * Vout clipped)
Vout clipped = 8/3 * (PV1 — 2 * Vlimit)
IN
= 2V
DD
P
= 3.3V, A
.
V
= 6dB, PV1 = 5V, Vlimit = 2V,
14
FIGURE 2. Soft Clipping vs No Clipping
20198729