YDA136 Datasheet, PDF (21/32 Pages) YAMAHA CORPORATION – D- 60 STEREO 60W-100W DIGITAL AUDIO POWER AMPLIFIER CONTROLLER

YDA136
■Protect Function
●Over Current Detection Function
YDA136 has a function to perform an over current protection by detecting a voltage drop of the current detection resistor
connected to the source side of PowerMOSFET.
When the voltage of an over-current detection terminal fulfills the following conditions, it judges that it is in an over-current
condition, and becomes over-current detection mode, and then a circuit is protected.
Voltage to be monitored
Low-Side over-current detection terminal (OCPLL, OCPLR） Voltage
High-Side over-current detection terminal（OCPHL, OCPHR） Voltage and VBB Potential difference
Over-current detection
mode threshold
< V_OC2
> V_OC1
In the example of peripheral circuit connection, the following four over-current conditions are detected, and then it becomes
an over-current detection mode.
・ A condition in which signals after LC filter and VSS power supply is shorted.
・ A condition in which signals after LC filter of non-inverted side and signals after LC filter of inverted side is
shorted.
・ A condition in which one side of a speaker was connected to LC filter, and another side of a speaker is shorted to
the VSS power supply.
In over-current detection mode, PROTN terminal is set to “L”, simultaneously it turns off all PowerMOSFET (hard mute)
and protects a circuit.
After it is made to over-current detection mode, even if an over-current condition is canceled, it is not canceled but is held
as it is.
Over-current detection mode can be canceled by intercepting a power supply or setting a PRSTN terminal to “L” at once.
●Power Detection Function
YDA136 monitors the following three kinds voltage.
When which voltage is less than regular voltage, it becomes low voltage detection mode.
Voltage to be monitored
IBB Terminal Voltage(It is proportional to the
voltage between V_BB and V_SS)
V_DD1 (Voltage between V_BB and V_BS)
V_DD2 (Voltage between V_DD and V_SS)
Constant Voltage Detection Mode Threshold
V_IB2
V_VB2
V_VD2
Here, since the IBB terminal has input the signal which divided VBB voltage, the IBB terminal will act as the monitor of
the VBB voltage.
Hard mute is operated in low voltage detection mode.
Among these, all registers are reset when V_DD2 voltage is less than threshold voltage (V_VD2).
Then, when three kinds of power supply voltage rises and a low voltage detection mode threshold is exceeded altogether,
the low voltage detection mode is canceled and a hard mute is also canceled after starting standby time (T_WAIT).
●Starting Standby Time Setup
Starting standby time (T_WAIT) can be set up by connecting a capacitor to the DET terminal of YDA136.
Be sure to set up to usually be set to T_WAIT>=600msec for internal initialization of YDA136.
The value of starting standby time (T_WAIT) and capacity (C_DET) of and the capacitor linked to a DET terminal serves as the
following relations.
T_WAIT = ６０(kΩ)×C_DET(F)
In the case of the capacity value (10μF) of the capacitor in the example of peripheral circuit connection, T_WAIT is set to
600msec.
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