■Overview
YDA139 (D-4) is a digital audio power amplifier IC with maximum output of 2.5W (RL=4Ω)×2ch. YDA139 has a “Pure Pulse Direct Speaker Drive Circuit” which directly drives speakers while reducing distortion of pulse output signal and reducing noise on the signal, and realizes the highest standard low distortion rate characteristics and low noise characteristics as the same class of output digital amplifier IC. In addition, circuit design with fewer external parts can be made depend on the condition of use because corresponds to filter less.
YDA139 has the power-down function which can minimize the power consumption in the standby state. In addition, high speed recovery function provided realizes recovery time within 1ms from the power-down state. Moreover, Over-current Protection function for speaker output terminals, IC Thermal Protection function, and POP Noise Reduction function are provided. YDA139 supports both digital signal input and analog signal input.

■Features
・Maximum output
WLCSP25
2.5 W×2ch (VDDP=VDDA=5.0V, RL=4Ω, THD+N=10%)
1.5 W×2ch (VDDP=VDDA=5.0V, RL=8Ω, THD+N=10%)
SSOP24
2.5 W×2ch （VDDP=VDDA=5.0V, RL=4Ω, THD+N=10%）
1.3 W×2ch （VDDP=VDDA=5.0V, RL=8Ω, THD+N=10%）
・Efficiency
WLCSP25
91 % (Analog input mode, VDDP=VDDA=5.0V, RL=8Ω, Po=1.5W)
SSOP24
88 % (Analog input mode, VDDP=VDDA=5.0V, RL=8Ω, Po=1.5W)
・Distortion Rate (THD+N)
0.03 % (Analog input mode, VDDP=VDDA=5.0V, RL=8Ω, Po=0.65W)
・S/N Ratio
99dB (Analog input mode, VDDP=VDDA=5.0V, Gain[1:0]=L,L)
・Over-current Protection function
・Thermal Protection function
・Low voltage Malfunction Prevention function
・Power-down function by PDN terminal
・Power-down High speed Recovery function
・Package
  Lead-free 25-ball WLCSP (YDA139-WZ)
  Lead-free 24-pin SSOP (YDA139-EZ)