tc7wbl3306cfk TOSHIBA Semiconductor CORPORATION, tc7wbl3306cfk Datasheet - Page 8

• Manufacturer Part Number: tc7wbl3306cfk
• Description: Low Voltage / Low Capacitance Dual Bus Switch
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Rise and Fall Times (tr / tf) of the TC7WBL3306C
The tr(out) and tf(out) values of the output signals are affected by the CR time constant of the input, which consists of
the switch terminal capacitance (C
In practice, the tr(out) and tf(out) values are also affected by the circuit’s capacitance and resistance components other
than those of the TC7WBL3306C, 3305C.
The tr(out) / tf(out) values can be approximated as follows. (Figure 3 shows the test circuit.)
tr(out) / tf(out) (approx) = - ( C
Calculation example:
Calculation conditions:
tr(out) (approx) = - ( 7 + 15 )E-12 ･ ( 120 + 6) ･ ln ( ( ( 3.0 - 0 ) – 1.5 ) / ( 3.0 – 0 ) )
V
Output of the previous IC = digital (i.e., high-level voltage = V
CC
= 3.0 V, C
Previous IC
R
DRIVE
R
≈ 1.9 ns
DRIVE
L
= output impedance of the previous IC
= 15 pF, R
An/Bn
DRIVE
I/O
+ C
I/O
= 120 Ω (output impedance of the previous IC), V
L
) and the on-resistance (R
TC7WBL3306C
TC7WBL3305C
) ･ (R
(Switch On)
Previous IC
R
DRIVE
Figure 3 Test Circuit
C
R
I/O
ON
DRIVE+
R
DRIVE
where R
= output impedance of the previous IC
R
ON
Bn/An
DRIVE
) ･ ln ( ( ( V
8
is the output impedance of the previous-stage circuit.
CC
ON
Parameter
; low-level voltage = GND)
) of the input.
,
Measure
Measure
3305C I/O Signals
Waveform generated with the TC7MBL3306C,3305C added
V
OH
M
Waveform generated without the TC7WBL3306C,3305C
– V
TC7WBL3306CFK,3305CFK
OL
3.3 ± 0.3 V
) – V
V
CC
tr(out)
M
M
/ 2
) / ( V
V
= 1.5 V (V
M
OH
– V
2.5 ± 0.2 V
CC
V
OL
V
CC
/ 2)
CC
tf(out)
2009-07-01
) )
/ 2
V
M
V
GND
CC
1.8 ± 0.15 V
V
V
V
CC
OH
OL
/ 2