WM8141 Wolfson Microelectronics Ltd., WM8141 Datasheet - Page 18

• Manufacturer Part Number: WM8141
• Description: WM8141 : 12-BIT 6MSPS Cis/ccd Analogue Front End/digitiser
• Manufacturer: Wolfson Microelectronics Ltd.

WM8141
REFERENCES
POWER SUPPLY
POWER MANAGEMENT
WOLFSON MICROELECTRONICS LTD
Figure 16 Internal VSMP Pulses Generated by Programmable VSMP Detect Circuit
The ADC reference voltages are derived from an internal bandgap reference, and buffered to pins
VRT and VRB, where they must be decoupled to ground. Pin VRX is driven by a similar buffer, and
also requires decoupling. The output buffer from the RLCDAC also requires decoupling at pin
VRLC/VBIAS
The WM8141 can run off either 3.3V or 5V single supplies or from split 5V (core) and 3.3V (digital
interface) supplies.
Power management for the device is performed via the Control Interface. The device can be powered
on or off completely by the EN bit. Alternatively, when control bit SELPD is high, only blocks selected
by further control bits (SELDIS[3:0]) are powered down. This allows the user to optimise power
dissipation in certain modes, or to define an intermediate standby mode to allow a quicker recovery
into a fully active state. In Line-by-line operation, the green and blue channel PGAs are automatically
powered down.
All the internal registers maintain their previously programmed value in power down modes and the
Control Interface inputs remain active. Table 3 summarises the power down control bit functions.
Table 3 Power Down Control
(VDEL = 000) INTVSMP
(VDEL = 001) INTVSMP
(VDEL = 010) INTVSMP
(VDEL = 011) INTVSMP
(VDEL = 100) INTVSMP
(VDEL = 101) INTVSMP
(VDEL = 110) INTVSMP
(VDEL = 111) INTVSMP
(VDEL = 000) INTVSMP
(VDEL = 001) INTVSMP
(VDEL = 010) INTVSMP
(VDEL = 011) INTVSMP
(VDEL = 100) INTVSMP
(VDEL = 101) INTVSMP
(VDEL = 110) INTVSMP
(VDEL = 111) INTVSMP
EN
0
1
X
INPUT
PINS
POSNNEG = 1
POSNNEG = 0
SELDPD
MCLK
VSMP
0
0
1
Device completely powers down.
Device completely powers up.
Blocks with respective SELDIS[3:0] bit high are disabled.
PD Rev 3.0 October 2000
Production Data
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