CDB44800 Cirrus Logic Inc, CDB44800 Datasheet - Page 54

• Manufacturer Part Number: CDB44800
• Description: BOARD EVAL FOR CS44800 PWM CTRL
• Manufacturer: Cirrus Logic Inc
• Series: Popguard®r

Specifications of CDB44800

• Amplifier Type: Class D
• Output Type: 8-Channel
• Voltage - Supply: 20 V ~ 50 V
• Operating Temperature: -10°C ~ 70°C
• Board Type: Fully Populated
• Utilized Ic / Part: CS44800
• Description/function: Audio DSPs
• Operating Supply Voltage: 5 V
• Product: Audio Modules
• For Use With/related Products: CS44800
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Max Output Power X Channels @ Load: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 598-1532; CDB-44800

54
7.5.4
7.6
7.6.1
7.6.2
RESERVED
7
Ramp Configuration (address 05h)
De-Emphasis Control (DEM[1:0])
Default = 00
00 - no de-emphasis
01 - 32 kHz de-emphasis filter
10 - 44.1 kHz de-emphasis filter
11 - 48 kHz de-emphasis filter
Function:
Enables the appropriate digital filter to maintain the standard 15 ms/50 ms digital de-emphasis filter re-
sponse.
Default = 00
00 - Ramp-up and ramp-down are disabled
01 - Ramp-up is disabled. Ramp-down is enabled.
10 - Reserved
11 - Ramp-up and ramp-down are enabled. Note that after a ramp-up sequence has completed, audio will
not play until RAMP[1:0] is set to 01.
Function:
When ramping is enabled, the duty cycle of the output PWM signal is increased (ramp-up) or decreased
(ramp-down) at a rate determined by the Ramp Speed variable (RAMP_SPDx). This function is used in
single-ended applications to reduce pops in the output caused by the DC-blocking capacitor. When the
ramp-up/down function is disabled in single-ended applications, there will be an abrupt change in the out-
put signal. Refer to Section 5.1.1 .
If ramp-up or down is not needed, as in a full-bridge application, these bits should be set to 00. If ramp-
up or down is needed, as in a single-ended half-bridge application, these bits must be used in the proper
sequence as outlined in
Down Sequence” on page
Ramp Speed (RAMP_SPD[1:0])
Default = 01
00 - Ramp speed = approximately 0.1 seconds
01 - Ramp speed = approximately 0.2 seconds
10 - Ramp speed = approximately 0.3 seconds
11 - Ramp speed = approximately 0.65 seconds
Function:
This feature is used in single-ended applications to reduce pops in the output caused by the DC-blocking
capacitor. The Ramp Speed sets the time for the PWM signal to linearly ramp-up and down from the bias
point (50% PWM duty cycle). Refer to Section 5.1.1
Ramp-Up/Down Setting (RAMP[1:0])
RESERVED
6
RESERVED
“Recommended Power-Up Sequence” on page 43
5
45.
RAMP1
4
RAMP0
3
RESERVED
2
and
RAMP_SPD1
“Recommended Power-
1
CS44800
RAMP_SPD0
DS632F1
0