Datasheet

TEF6901A_3 © NXP B.V. 2008. All rights reserved.
Product data sheet Rev. 03 — 20 March 2008 70 of 107
NXP Semiconductors
TEF6901A
Integrated car radio
[1] The VU-meter mode can be used with external sources only. When the VU-meter mode is active, the radio
quality detection of USN, MOD and offset is limited to AF update tuning only. During VU-meter mode the
bits MOD[4:0] indicate the external source input amplitude. The FM dynamic bandwidth control is disabled
and a fixed bandwidth of 113 kHz is defined. However, other fixed bandwidth settings are available by
DYN = 0 and the setting of BW; data byte 0h (see Table 28). See Table 99 for compression recovery timing
control. VU-meter mode is automatically activated when audio compression is on (COMP = 1).
[1] Setting HTC[2:0] is also in use for setting the timing of weak signal high cut control during radio operation.
3 LDHB loudness high boost; see Figure 39
0 = loudness control is limited to bass gain
1 = loudness controls bass gain and treble gain
2 to 0 LDS[2:0] loudness start setting; loudness start defines the volume setting below
which loudness control is activated; see
Table 100 and Figure 39
Table 99. VU-meter timing; HTC[2:0] of data byte 0Bh; TIMING
[1]
HTC2 HTC1 HTC0 t
attack
t
recovery
0 0 0 0.02 s 0.03 s
0 0 1 0.02 s 0.06 s
0 1 0 0.02 s 0.2 s
0 1 1 0.02 s 5 s
1 0 0 0.02 s 0.6 s
1 0 1 0.02 s 10 s
1 1 0 0.02 s 1 s
1 1 1 0.02 s 2 s
Table 100. Loudness start
LDS2 LDS1 LDS0 Start of loudness at volume setting
000−12 dB
001−16 dB
010−20 dB
011−24 dB
100−28 dB
101−32 dB
110−36 dB
111−40 dB
Table 98. LOUDNESS - data byte 17h bit description
…continued
Bit Symbol Description