tc7mbl6126s TOSHIBA Semiconductor CORPORATION, tc7mbl6126s Datasheet - Page 7

• Manufacturer Part Number: tc7mbl6126s
• Description: Quad Low Voltage/low Capacitance Bus Switch
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Rise and Fall Times (tr / tf) of the TC7MBL6125S,6126S I/O Signals
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 TC7MBL6125S,6126S.
The tr / tf (out) values can be approximated as follows. (Figure 3 shows the test circuit.)
Calculation example:
tr / tf out (approx) = - ( C
tr out (approx) = - ( 12 + 15 )E-12 ･ ( 120 + 9) ･ ln ( ( ( 3.0 - 0 ) – 1.5 ) / ( 3.0 – 0 ) )
V
Calculation conditions:
Output of the previous IC = digital (i.e., high-level voltage = V
CC
= 3.0V , C
≈ 2.4 ns
Previous IC
R
DRIVE
R
L
DRIVE
= 15pF , R
= output impedance of the previous
I/O
An/Bn
DRIVE
+ C
L
) ･ (R
I/O
= 120Ω(output impedance of the previous IC), V
) and the on-resistance (R
TC7MBL6125S
TC7MBL6126S
(Switch On)
Previous IC
R
DRIVE+
DRIVE
Figure 3 Test Circuit
C
R
I/O
ON
R
DRIVE
where, R
= output impedance of the previous
R
ON
) ･ ln ( ( ( V
Bn/An
DRIVE
7
CC
ON
is the output impedance of the previous-stage circuit.
Parameter
OH
TC7MBL6125S,6126SFT/FK/FTG
; low-level voltage = GND)
) of the input.
Measure
Measure
V
– V
M
Waveform generated with the TC7MBL6125S,6126S added
OL
Waveform generated without the TC7MBL6125S, 6126S
) – V
3.3 ± 0.3 V
M
V
) / ( V
CC
M
tr out
/ 2
= 1.5V(V
V
OH
M
– V
OL
CC
2.5 ± 0.2 V
/ 2)
) )
V
V
CC
CC
2007-10-19
tf out
/ 2
V
M
V
GND
CC
1.8 ± 0.15 V
V
V
V
CC
OH
OL
/ 2