wm8903 Wolfson Microelectronics plc, wm8903 Datasheet - Page 65

• Manufacturer Part Number: wm8903
• Description: Ultra Low Power Codec For Portable Audio Applications
• Manufacturer: Wolfson Microelectronics plc

Pre-Production
ANALOGUE OUTPUTS
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The WM8903 has eight analogue output pins:
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The output signal paths and associated control registers are illustrated in Figure 33.
HEADPHONE OUTPUTS – HPOUTL AND HPOUTR
The headphone outputs are designed to drive 16Ω or 32Ω headphones. These outputs are ground-
referenced, i.e. no series capacitor is required between the pins and the headphone load. They are
powered by an on-chip charge pump (see “Charge Pump” section).
Signal volume at the headphone outputs is controlled as shown in Table 40.
LINE OUTPUTS – LINEOUTL AND LINEOUTR
The line outputs are similar to the headphone outputs in design. They are ground-referenced and
power by the on-chip charge pump. However, these outputs are intended for driving line loads, as the
charge pump powering both the Headphone and Line outputs can only provide sufficient power to
drive one set of headphones at any given time.
Signal volume at the line outputs is controlled as shown in Table 41.
DIFFERENTIAL LINE OUTPUTS – LON/LOP AND RON/ROP
The differential line outputs are designed to differential line loads, including external loudspeaker
drivers. The WM9001 is an ideal component for driving loudspeakers from these outputs. These pins
are referenced to VMID (AVDD/2) and are powered directly from the AVDD supply.
Signal volume at the differential line outputs is controlled as shown in Table 42.
Headphone outputs, HPOUTL and HPOUTR
Line outputs, LINEOUTL and LINEOUTR
Differential line outputs, LON/LOP and RON/ROP
PP, Rev 3.1, August 2009
WM8903
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