YDA139 Datasheet, PDF (7/18 Pages) YAMAHA CORPORATION – D- 4 STEREO 2.5W DIGITAL AUDIO POWER AMPLIFIER

YDA139
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●Protection Function
YDA139 has the following protection functions for the digital amplifier: Over-current Protection function, Thermal
Protection function, Low voltage Malfunction Prevention function, and Power supply voltage fluctuation protection
function.
Over-current Protection function
This is a function to make the Over-current Protection Mode by detecting a short-circuiting (Ground short/Power supply
short/Short between terminals) in the output stage of digital amplifier and to disable (WL) the output stage of the digital
amplifier. When entering the Protection Mode, automatically it returns to the normal operation after a given waiting
time(T_WT). If short circuiting in the output stage continues, the sequence is repeated: short circuit detection, protection mode
(T_WT), and automatic recovery.
Thermal Protection function
This is a function to make the Thermal Protection Mode by detecting extraordinary high temperature of YDA139 and to
disable (WL) the output stage of the digital amplifier. This Protection mode is automatically returned to the normal
operation state when internal temperature of YDA139 is lowered sufficiently.
Low voltage Malfunction Prevention function
YDA139 has this Prevention function so as not to cause malfunction in the low power supply voltage. When AVDD
voltage becomes lower than V_UVLL, the Protection mode is operated to disable (WL) the output stage of the digital amplifier.
When AVDD voltage becomes higher than V_UVLH, the protection mode is cancelled after a given waiting time and turns into
the normal mode.
Power supply Voltage Fluctuation Detection function
YDA139 has this detecting function so that noise may not be generated from speakers when AVDD voltage was lowered
significantly. When AVDD voltage becomes lower than V_ML, the protection mode is operated to disable (WL) the output
stage of the digital amplifier. When AVDD voltage becomes higher than V_ML, the protection mode is cancelled and turned
into the normal operation mode.
●Pop noise reduction
When used in Digital Input mode (MOD[1:0]=L,L) and Mixing mode (MOD[1:0]=H,L), cut power off after setting PDN
terminal to “L” in order to reduce the pop noise.
●Snubber Circuit
When use in power supply voltage 4.5V or more, connect the RC snubber circuit between each output terminal (Lch:
between OUTPL and OUTML, Rch: between OUTPR and OUTMR, near IC).
The constant and the snubber circuit are as follows.
Power supply voltage range
R
C
4.5 to 5.25V
1Ω
330pF ^*1
*1: Use the temperature compensated capacitor.
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