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Details, datasheet, quote on part number:NJU8755V
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| Part: | NJU8755V |
| Category: | Multimedia => Audio => Amplifiers => Power Amplifiers => Class D Amplifier |
| Description: | Analog Signal Input Stereo Class D Power Amplifier |
| Company: | NJR Corporation |
| Datasheet: | Download NJU8755V datasheet File size : 88 kB |
| Request For quote: | Find where to buy NJU8755V
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Datasheet text preview:
NJU8755
PRELIMINARY
Analog Signal Input Stereo Class D Power Amplifier
! GENERAL DESCRIPTION
The NJU8755 is an analog signal input stereo class D power amplifier. The NJU8755 includes Inversion operational amplifier input circuit, PWM modulators, an output-short protector and a low voltage detector. The NJU8755 incorporates BTL amplifiers, which eliminate AC coupling capacitors, capable of driving up to 1.2W/channel with simple external LC low-pass filters. Class-D operation achieves high power-efficiency, which achieves longer battery life for battery powered applications, thus the NJU8755 is suited for portable audio, note-PC, etc.
! PACKAGE OUTLINE
NJU8755V
! FEATURES
# # # # # # # #
! PIN CONFIGURATION
1 2 3 4 5 6 7 8 9 10 20 19 18 17 16 15 14 13 12 11 VSS INR COM STBY VDDR O U T RP VSSR O U T RN VDDR VDDR VDDL
2-Channel Analog Signal Input VDD 2-Channel BTL Outputs :1.2W/channel at 5V into 8Ohms INL Standby(Hi-Z), Mute Control TEST Built-in Short Protector MUTE Built-in Low Voltage Detector VDDL Operating Voltage 2.7 ~ 5.25V OUTLP CMOS Technology VSSL Package Outline SSOP20 OUTLN VDDL VDDL ! BLOCK DIAGRAM VDD VSS
INL
+ +
Pulse Width Modulator
OUTLP VSSL VDDL OUTLN VSSL VDDR
Pulse Width Modulator
COM + + INR -
OUTRP VSSR VDDR OUTRN VSSR
Short Protector
Soft Start
Control
Logic
Low Voltage Detector
MUTE
STBY
TEST
Ver.2003-03-12
-1-
NJU8755
! PIN DESCRIPTION
No. 1 2 3 4 5 9 10 6 7 8 11 12 16 13 14 15 SYMBOL VDD INL TEST MUTE VDDL OUTLP VSSL OUTLN VDDR OUTRN VSSR OUTRP I/O - I I I - O - O - O - O FUNCTION Power Supply : VDD=5.0V L-channel signal input Maker test This pin must be connected to GND. Mute control Low : Mute ON High : Mute OFF L-channel Power Supply : VDDL=5.0V L-channel positive output L-channel Power GND L-channel negative output R-channel Power Supply : VDDR=5.0V
R-channel negative output R-channel Power GND : VSSR=0V R-channel positive output Standby control 17 STBY I Low : Standby ON High : Standby OFF 18 COM - Analog common 19 INR I R-channel signal input 20 VSS - Power GND : VSS=0V *The relations of "VSS= VSSL= VSSR=0V" and "VDD= VDDL=VDDR" must be maintained. *Pin No.4(MUTE) and 17(STBY) must be connected to VDD, when these pins are not used.
-2-
Ver.2003-03-12
NJU8755 NJU3555
! FUNCTIONAL DESCRIPTION
(1) Signal Output The OUTLP/LN and OUTRP/RN generate respectively L-channel and R-channel PWM output signals, which will be converted to analog signal via external 2nd-order or higher LC filter. A switching regulator with a high response against a voltage fluctuation is the best selection for the VDDL and VDDR, which are the power supply for output drivers. To obtain better THD performance, the stabilization of the power is required. (2) Standby By setting the STBY pin to "L", the standby mode is enabled. In the standby mode, the entire functions of the NJU8755 enter a low-power state, and the output pins(OUTLP/LN and OUTRP/RN) are high impedance. (3) Mute By setting the MUTE pin to "L", the Mute function is enabled. In the Mute mode, the output pins(OUTLP/LN and OUTRP/RN) output square wave(Duty: 50%). (4) Low Voltage Detector When the power supply voltage drops down to below VDD(MIN), the internal oscillation is halted for prevention to generate unwanted frequency, and the output pins(OUTLP/LN and OUTRP/RN) become in high impedance. (5) Short Circuit Protection The short protector, which protects the NJU8755 against high short-circuit current, turns off the output drivers of L-channel and R-channel independently. After about 5 seconds from the protection, the NJU8755 returns to normal operation. The short protector functions at following accidents.
· Short · Short · Short · Short · Short · Short
between OUTLP and OUTLN between OUTLP and VSSL between OUTLN and VSSL between OUTRP and OUTRN between OUTRP and VSSR between OUTRN and VSSR
Note 1)
The detectable current and the period for the protection depend on the power supply voltage and ambient temperature. Note 2) The short protector is not effective for a long term short-circuit but for an instantaneous accident. Continuous high-current may cause permanent damage to NJU8755.
Ver.2003-03-12
-3-
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