iC-GF
TRANSCEIVER
Rev C1, Page 15/26
DEFAULT MODE
CHANNEL 2
IN2 QCFG2 OEN QN2 QP2
Enabling the switches
Setting pin OEN to low unconditionally disables all four
output switches. Other functions of the chip (like the
DC/DC converter or the feedback channel) remain en-
abled.
X
L
H
L
H
L
H
X
Z
Z
H
H
L
L
off
on
off
off
off
off
on
off
off
on
off
on
off
off
H
H
H
H
H
H
Configuring the switches
The functionality of the switches is determined by the
pins QCFG1 and QCFG2. A voltage at QCFGx which
is lower than Va()lo (cf. Figure 8) deactivates the rel-
evant high-side switches; with a voltage higher than
Va()hi the relevant low-side switches are deactivated.
Both high-side and low-side switches are activated,
when the pin is left open.
L
Table 3: Function table Channel 2 (INV1 = H, L)
Tables 2 and 3 show the switch configuration for both
channels, with respect to the input pins.
Valo()hys
QPx active
Feedback channel CFI–CFO configuration
The feedback channel CFI–CFO polarity can be con-
figured via pin CFP (see table 4). This pin also sets
the pull-up/down current at pin CFI.
Vahi()hys
QNx active
Va()lo
Va()hi
V(QCFGx)
FEEDBACK CHANNEL
CFI CFP CFO PULL at CFI pin
Figure 8: Levels at QCFG1/QCFG2 for switch con-
figuration
H
H
L
H
L
H
L
Z
L
L
Z
UP
DOWN
UP
CHANNEL 1
IN1 QCFG1 INV1 OEN QN1 QP1
L
DOWN
X
L
H
L
H
L
H
L
H
L
H
L
X
Z
Z
Z
Z
H
H
H
H
L
X
L
L
H
H
L
L
off
on
off
off
on
off
off
off
off
off
on
on
off
off
off
on
on
off
off
on
on
off
off
off
off
off
Table 4: Function table Feedback Channel
H
H
H
H
H
H
H
H
H
H
H
H
Undervoltage signalling
Undervoltage at VBO, VCC or VCC3 is signalled at
pin NUVD. A valid undervoltage event is signalled at
NUVD for at least 35 ms (cf. Electrical Characteristics
No. 405 ) resp. as long as the duration of the undervolt-
age situation.
L
H
H
L
L
H
H
L
L
L
H
Table 2: Function table Channel 1
ICHAUS [ IC-HAUS GMBH ]
