wm8400 Wolfson Microelectronics plc, wm8400 Datasheet - Page 142

• Manufacturer Part Number: wm8400
• Description: Wolfson Audioplustm Hi-fi Audio Codec And Power Management Unit For Mobile Multimedia
• Manufacturer: Wolfson Microelectronics plc

WM8400
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Table 89 DC-DC Converter and LDO Regulator Voltage Setting (Hardware)
VSEL
R2
R1
DC1VSEL connected
to 0v
Output voltage = 1.2v
DC1VSEL connected
to 2.4v
Output voltage = 1.35v
DC1VSEL connected
to Output * (R1 /
(R1+R2))
Output voltage = 0.625
* (R1+R2) / R1
Table 88 DC-DC Converter Output Voltage
During Start-Up, the output voltage of the DC-DC Converters and LDO1 and LDO2 Regulators may
be set in hardware using the DC1VSEL, DC2VSEL, LDO1VSEL and LDO2VSEL pins respectively.
Hardware control of the output voltage is implemented by setting these pins to a logic level or by
connecting the voltage select pin to a potential divider on the output of the corresponding converter
or regulator. (In the case of the DC-DC Converters, the ‘Output’ is the DC1FB or DC2FB pin.)
The hardware voltage select pins are checked during Start-Up, and the applicable voltage select
registers are set to the equivalent values by the WM8400. On completion of Start-Up, and once
PWRGOOD has been asserted, the voltage select pins have no further effect, and control is passed
to the software controlled registers only.
The hardware configurations are illustrated in Table 89.
DC1_VSEL,
DC2_VSEL
0011011
0011100
0011101
0011110
0011111
0100000
0100001
0100010
0100011
0100100
0100101
0100110
0100111
0101000
0101001
0101010
DC1
DC OUTPUT
1.525v
1.550v
1.575v
1.600v
1.625v
1.650v
1.675v
1.700v
1.725v
1.750v
1.775v
1.800v
1.825v
1.850v
1.875v
1.900v
DC2VSEL connected
to 0v
Output voltage = 2.8v
DC2VSEL connected
to 2.4v
Output voltage = 3.3v
DC2VSEL connected
to Output * (R1 /
(R1+R2))
Output voltage = 0.625
* (R1+R2) / R1
DC2
DC1_VSEL,
DC2_VSEL
1000110
1000111
1001000
1001001
1001010
1001011
1001100
1001101
1001110
1001111
1010000
1010001
1010010
1010011
1010100
1010101
LDO1VSEL connected
to 0v
Output voltage = 1.2v
LDO1VSEL connected
to 2.4v
Output voltage = 1.35v
LDO1VSEL connected
to Output * (R1 /
(R1+R2))
Output voltage = 0.625
* (R1+R2) / R1
DC OUTPUT
2.600v
2.625v
2.650v
2.675v
2.700v
2.725v
2.750v
2.775v
2.800v
2.825v
2.850v
2.875v
2.900v
2.925v
2.950v
2.975v
LDO1
DC1_VSEL,
DC2_VSEL
1110001
1110010
1110011
1110100
1110101
1110110
1110111
1111000
1111001
1111010
1111011
1111100
1111101
1111110
1111111
LDO2VSEL connected
to 0v
Output voltage = 1.8v
LDO2VSEL connected
to 2.4v
Output voltage = 3.3v
LDO2VSEL connected
to Output * (R1 /
(R1+R2))
Output voltage = 0.625
* (R1+R2) / R1
PP, April 2009, Rev 3.0
DC OUTPUT
LDO2
3.675v
3.700v
3.725v
3.750v
3.775v
3.800v
3.825v
3.850v
3.875v
3.900v
3.925v
3.950v
3.975v
4.000v
4.025v
Pre-Production
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