isp1109 NXP Semiconductors, isp1109 Datasheet - Page 11

• Manufacturer Part Number: isp1109
• Description: Universal Serial Bus Transceiver With Carkit Support
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 13355
Product data sheet
7.7 Audio switches
7.8 ISET detector
The audio switches provide low impedance path for analog audio signals to be multiplexed
on the DP and DM lines, or loopback between the MIC and SPKR lines.
There are five analog switches that are controlled by register bits. The impedance of the
switches will be between 50
bits and the switches.
Table 5:
The ISET detector will set the ISET pin HIGH when either of the following conditions is
met:
The DP and DM SE1 detector will time the length of the SE1 condition. The timer value is
programmable using register bit TMR_SE1. The timer ranges from 0 ms to 15 ms, with
1 ms interval.
The ID > V
In Power-down mode, the bias current is turned off to minimize current I
current needs to be enabled so that the ISET detector can function as described earlier.
AUDIO_EN
0
1
1
Fig 5. Audio switches.
•
•
•
ID > V
DP and DM SE1 detected, V
If the Power-down is because V
V
BUS
voltage goes above the SESS_VLD threshold.
th(ID_FM)
Audio switch control
th(ID_FM)
, V
AUDIO_MONO
X
0
1
detector, and the SE1 detector (with timer) requires bias current.
DM
DP
CC
Figure 5
Rev. 01 — 14 July 2005
> V
th(ISET)
and 150 .
shows the audio switches.
CC
and V
CC(I/O)
> V
S1
off
on
off
S3
S1
S2
th(ISET)
BUS
is disconnected, the bias will be enabled if the
Table 5
> V
and V
th(svc)
shows the relation between the control
USB transceiver with carkit support
SW_MIC_
SPKR_L
SW_MIC_
SPKR_R
BUS
004aaa518
S2
off
off
on
> V
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
th(svc)
SPKR_R
MIC
SPKR_L
.
CC
ISP1109
S3
off
on
off
. The bias
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