Sharp LC-24LE250EK (serv.man2) Service Manual ▷ View online
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LC-24LE250 (C)
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Table 3: Recomnended operating conditions
B. MAIN AMPLIFIER (TS4962M)(2.5 W option)
a. General Description
The TS4962M is a differential Class-D BTL power amp lifier. It is able to drive up to 2.3W
into a 4
Ω
load and 1.4W into a 8 Ω load at 5V. It achieves outstanding efficiency (88 %typ.)
compared to classical Class-AB audio amps. The gain of the device can be controlled via two
external gain-setting resistors. Pop & click reduct ion circuitry provides low on/off switch
noise while allowing the device to start within 5ms
external gain-setting resistors. Pop & click reduct ion circuitry provides low on/off switch
noise while allowing the device to start within 5ms
.A standby function (active low) allows
the reduction of current consumption to 10nA typ.
b. Features
- Operating from VCC = 2.4V to 5.5V
- Standby mode active low
- Output power: 3W into 4 Ω and 1.75W into 8 Ω
- with 10% THD+N max and 5V power supply.
- Output power: 2.3W @5V or 0.75W @ 3.0V
- into 4 Ω with 1% THD+N max.
- Output power: 1.4W @5V or 0.45W @ 3.0V
- into 8 Ω with 1% THD+N max.
- Adjustable gain via external resistors
- Low current consumption 2mA @ 3V
- Efficiency: 88% typ.
- Signal to noise ratio: 85dB typ.
- PSRR: 63dB typ. @217Hz with 6dB gain
- PWM base frequency: 250kHz
- Standby mode active low
- Output power: 3W into 4 Ω and 1.75W into 8 Ω
- with 10% THD+N max and 5V power supply.
- Output power: 2.3W @5V or 0.75W @ 3.0V
- into 4 Ω with 1% THD+N max.
- Output power: 1.4W @5V or 0.45W @ 3.0V
- into 8 Ω with 1% THD+N max.
- Adjustable gain via external resistors
- Low current consumption 2mA @ 3V
- Efficiency: 88% typ.
- Signal to noise ratio: 85dB typ.
- PSRR: 63dB typ. @217Hz with 6dB gain
- PWM base frequency: 250kHz
- Low pop & click noise
- Thermal shutdown protection
- Available in flip-chip 9 x 300 µm (Pb-free)
- Thermal shutdown protection
- Available in flip-chip 9 x 300 µm (Pb-free)
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LC-24LE250 (C)
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c.
Pin descriptions and functions:
Figure 3: Pin description
Table 4: Recommended operating conditions
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LC-24LE250 (C)
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C. HEADPHONE AMPLIFIER STAGE
Headphone is a SoC (single on chip) configuration in mainboard, design scheme is shown
in figure 4.
Figure 4: Headphone
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LC-24LE250 (C)
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4.
POWER STAGE
Figure 5: Power socket and power options
Power socket is used for taking voltages which are 3.3V, 12V, 5V and 24V(VDD_Audio).
These voltages are produced in power card. Also socket is used for giving dimming, backlight
and standbye signals with power card.
t is shown in figure 5.
24V(VDD_Audio) goes directly to the audio side, through power socket other incoming
voltages from power card are converted several voltages.
Figure 6: Power steps
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