ISL54103 Datasheet, PDF (6/7 Pages) Intersil Corporation – DDC Accelerator (DDCA)

ISL54103
consumption. When either of the two signals is pulled LOW,
an active pull-up current of 275µA maintains a good V_OL
noise margin.
When the bus line is released, it is pulled high by the
ISL54103 active current until the voltage exceeds the
V_TRIPL level for a period of time. This voltage-time
combination filters out noise on the signal line. Once the
ISL54103 detects a valid rising edge, a 2.2mA boost current
pulls the bus line high very quickly (see Figure 8). This boost
current turns off when the input level reaches the V_TRIPH
threshold and the pull-up current returns to the active level. If
both inputs are HIGH, the pull-up current drops to the
standby level of 100µA.
V_TRIPH
With ISL54103 DDCA
V_DD
V_TRIPH
With DDCA
Without DDCA
V_TRIPL
Gnd
>20Vns
(Typical)
DDC1
t
DDC2
FIGURE 10. NOISE SUPPRESSION. BOOST CURRENT
APPLIED WHEN INPUT SIGNAL EXCEEDS 20Vns
(TYPICAL)
V_TRIPL
With RC
Pullup
R = 15.8K
C = 200pF
FIGURE 8. ISL54103 DDC SYSTEM BOOST PULL-UP
COMPARED TO RESISTOR PULL-UP
(V_DD = 5.5V)
With ISL54103 DDCA
V_TRIPH
V_TRIPL
With RC
Pullup
R = 15.8K
C = 200pF
FIGURE 9. ISL54103 DDC SYSTEM BOOST PULL-UP
COMPARED TO RESISTOR PULL-UP
(V_DD = 2.7V)
6
FN6303.1
June 22, 2006