CS43131 datasheet(34/156 Pages) CIRRUS

Part #	CS43131

Description	130-dB, 32-Bit High-Performance DAC with Integrated Headphone Driver and Impedance Detection

PDF	156 Pages

Scroll/Zoom	100%

Manufacturer	CIRRUS [Cirrus Logic]

Direct Link	http://www.cirrus.com

Logo

34 / 156 page

DS1155F1

CS43131

4.3 Class H Amplifier Output

4.3.2

Power-Supply Transitions

Charge-pump transitions from the lower to the higher set of rail voltages occur on the next FLYN/FLYP clock cycle. Despite

the system’s fast response time, the VCP_FILT pin’s capacitive elements prevent rail voltages from changing instantly.

Instead, the rail voltages ramp up from the lower to the higher supply, based on the time constant created by the output

impedance of the charge pump and the capacitor on the VCP_FILT pin (the transition time is approximately 20 µs).

Fig. 4-4 shows Class H supply switching. During this charging transition, a high dv/dt transient on the inputs may briefly

clip the outputs before the rail voltages charge to the full higher supply level. This transitory clipping has been found to be

inaudible in listening tests.

Figure 4-4. VCP_FILT Transitions

When the charge pump transitions from the lower to higher set or rail voltage, there is no delay associated with the

transition.

+VCP

Ideal Transition

Actual Transition caused

by VCP_FILT+ Capacitor

Time

+VP_LDO

-VCP

-VP_LDO

CS43131 Datasheet(PDF) 34 Page - Cirrus Logic