VAISH VS3125

VS3125
Quad Bus Switch with
Individual Active Low Enables
Applications
•=
5v to 3.3V translation in mixed supply environment
•=
Clock gating
•=
Hot Swap interface
•=
Logic replacement
•=
Video, audio switching
General Description
The VS3125 contains a set of four high-speed, low-resistance bus switches. Each bus switch is individually
controlled by TTL-compatible, active-low control input (/xOE). The low ON resistance of VS3125 allows
inputs to be connected to outputs without adding propagation delay and without generating additional signal
noise.
The VS3125 is function and pinout compatible with QS3125. It enables 5V to 3.3V level translation when
used with an external diode in the power supply line. In addition, the high off-isolation between switch
terminals in the ‘disable’ mode, and the near-zero propagation delay in the ‘on’ state make the VS3V125 an
ideal interface element for hot-swapping applications.
Features
•=
Enhanced N-FET with no dc path to VCC or
GND in normal operating signal voltage range.
•=
Near-zero propagation delay
•=
Undershoot clamp diodes on all
switch and control pins
•=
Low impedance bidirectional data flow
•=
Pin-compatible with QS3125 & PI5C3125
switches
•=
ESD rating >2000V (Human Body
Model) or >200V (Machine Model)
•=
Zero added ground bounce or signal noise
•=
Latch-up current >100mA
•=
TTL-compatible control signals
•=
Available in 150-mil wide QSOP
package
Figure 1. Functional Block Diagram
1A
2A
Figure 2. Pin Configuration
3A
4A
QSOP
/1OE
/2OE
/3OE
/4OE
1Y
2001-04-12
2Y
3Y
4Y
NC
1
16
VCC
/1OE
1A
2
15
/4OE
3
14
4A
1Y
4
13
4Y
/2OE
2A
5
6
12
11
2Y
7
10
/3OE
3A
3Y
GND
8
9
NC
All Pins, Top View
NC= No Connect
Page 1
MDSS-0011-01
www.vaishali.com
Vaishali Semiconductor 747 Camden Avenue, Suite C Campbell CA 95008 Ph. 408.377.6060 Fax 408.377.6063
VS3125
Table 1. Pin Description
Name
I/O
Description
1A – 4A
I/O
Data Input or Output
1Y – 4Y
I/O
Data Input or Output
/1OE - /4OE
I
Bus Switch Enable
Table 2. Function Table
/xOE
Path
Function
L
xA <-> xY
Enable switch
H
High Impedance
Disable switch
Table 3. Absolute Maximum Ratings
Supply Voltage to Ground………………………….…..-0.5V to +7.0V
DC Switch Voltage VS……………………….………….-0.5V to +7.0V
DC Input Voltage VIN…………………………… ……...-0.5V to +7.0V
AC Input Voltage (Pulse Width < 20ns)……………….…………-3.0V
DC Output Sink Current per Switch Pin…………………...…..120mA
Maximum Power Dissipation…………………………….…..0.5 Watts
o
o
Storage Temperature………………………………...-65 C to +150 C
Note ABSOLUTE MAXIMUM CONTINUOUS RATINGS are those values beyond which damage to the device may
occur. Exposure to these conditions or conditions beyond those indicated may adversely affect device reliability.
Functional operation under absolute maximum rated conditions is not implied.
Table 4. Capacitance
o
TA = 25 C, f = 1MHz, VIN = 0V, VOUT = 0V
QSOP
Pins
Typ
Max
Unit
Control Inputs
4
5
pF
VSwitch Channels ( Switch OFF )
5
7
pF
Note Capacitance is guaranteed, but not production tested. Total capacitance of a path, when the switch is closed, is
the sum of the switch terminal capacitances.
Table 5. Recommended Operating Conditions
Symbol
Parameter
Min
Max
Units
VCC
Power supply voltage
4.5
Typ
5.5
V
VIL
Low level input voltage
-0.5
0.8
V
2.0
5.5
V
-40
85
o
(Control inputs)
VIH
High level input voltage
(Control inputs)
TA
Operating free-air temperature
C
Note: All unused control inputs of the device must be held at Vcc or GND, to ensure proper device operation
2001-04-12
Page 2
MDSS-0011-01
www.vaishali.com
Vaishali Semiconductor 747 Camden Avenue, Suite C Campbell CA 95008 Ph. 408.377.6060 Fax 408.377.6063
VS3125
Table 6. Electrical Characteristics Over Recommended Operating Free-air Temperature Range
Symbol
Parameter
Test Conditions
VIK
Clamp Voltage
Control Inputs
Min
Typ
(1)
VCC = Min., IIK = -18mA
Switch I/O
VOH
Logic High Voltage
Max
Units
-1.5
V
-1.5
Switch I/O
VCC= 4.3V,VIN = 5V
VIN = VCC = 5V, IOUT = -5µA
3.7
3.9
4.1
VCC= 4.3V,VIN = 5V,
3.0
3.3
3.6
V
IOUT = -100µA
|II|
Input Leakage
Current
Control Inputs
VCC = Max., VI = VCC or GND
1
µA
|OFF|
Power OFF Leakage
Current
Control Inputs
VCC = 0, VI or VO = VCC or GND.
1
µA
VCC = Max., VI/O = VCC,
1
µA
|IOZ|
Switch I/O
OFF State Leakage
Current
Switch I/O
IODL
Switch I/O Drive
Current (Logic LOW)
VCC = Min, VIN = 0, VOUT = 0.4V
50
mA
IODH
Switch I/O Drive
Current (Logic HIGH)
VCC = Min, VIN = VCC, VOUT = 2.4V
-50
mA
RON
Switch ON
(2)
Resistance
VCC = 3.0V, VIN = 0, IOUT = 15mA
/xOE= VCC
Notes:
1.
2.
5
(2)
7
Ω
o
Typical value is specified at VCC = 5V and TA = 25 C.
RON is measured by forcing specified current into the ‘output’ node of the switch with the ‘input’ node of the switch
at the specified voltage.
Table 7. Power Supply Characteristics Over Recommended Operating Free-air Temperature Range
(1)
Symbol
Parameter
Test Conditions
Max
Units
ICCQ
Quiescent Power Supply Current
VCC = Max.,/xOE = VCC or GND, f = 0
1
µA
∆ICC
Power Supply Current per Input
(2)
High
VCC = Max, VIN = 3.4V, f = 0
1.5
mA
QCCD
Dynamic Power Supply Current
VCC = Max, Switch pins open, Control Inputs
toggling at 50% duty cycle
0.25
mA/MHz
(3)
Notes:
1.
2.
3.
For conditions shown as Min or Max, use the appropriate values specified under Recommended Operating
Conditions.
Per control input. All other control inputs at GND. Switch I/O pins do not contribute to ∆ICC.
This parameter represents the average dc current resulting from the switching of internal nodes of the device at a
given frequency. The switch I/O pins make insignificant contribution to the dynamic power supply current of the
device. This parameter is guaranteed, but not production tested.
2001-04-12
Page 3
MDSS-0011-01
www.vaishali.com
Vaishali Semiconductor 747 Camden Avenue, Suite C Campbell CA 95008 Ph. 408.377.6060 Fax 408.377.6063
VS3125
Figure 4. VOH CHARACTERISTICS
Figure 3. VOLTAGE TRANSLATION
Vout
(V)
5
4.5
4
4.0
VCC = 4.3V
3
VOH
TA = 85°C
TA = 25°C
TA = - 40°C
3.5
Output Voltage
2
3.0
(V)
2.5
1
2.0
0
1
0
2
3
4
4.5
5
Vin (V)
4.75
5.0
5.25
5.5
VCC – Supply Voltage (V)
Figure 5. Voltage Translation. Application
VCC = 5V
1N4148
or equivalent
10K
VCC
5V
DEVICE
I/O
I/O
3.3V
DEVICE
VS3125
/E
2001-04-12
Page 4
MDSS-0011-01
www.vaishali.com
Vaishali Semiconductor 747 Camden Avenue, Suite C Campbell CA 95008 Ph. 408.377.6060 Fax 408.377.6063
VS3125
Table 8. Switching Characteristics Over Operating Range
o
o
TA = -40 C to +85 C, VCC = 5V + 10%
CLOAD = 50pF, RLOAD = 500Ω unless otherwise stated.
Symbol
Description
(1)
Min
(2,3)
tPLH, tPHL
Data Propagation Delay
tPZH, tPZL
Switch Turn-on Delay, /xOE to xA or xY
tPLZ, tPHZ
Switch Turn-off Delay
through the switch
(3)
, /xOE to xA or xY
(3)
Max
Units
-
0.25
ns
1.5
6.5
ns
1.5
5.5
ns
Notes:
1.
2.
3.
See test circuits and waveforms.
This parameter is the calculated theoretical RC time constant of ON-state resistance of the switch and the
specified load capacitance when driven by an ideal voltage source (zero source impedance). This time-constant is
of the order of 0.25ns for VS3125. Since this time-constant is much smaller than rise/fall times of typical driving
signals, it adds very little propagation delay to the system.
This parameter is guaranteed, but not production tested.
Figure 6. AC Test Circuit and Switching Waveforms
AC Test Circuit
Load Switch Position
S1
7V
VIN
Pulse
Generator
VOUT
500Ω
DUT
RL
450Ω
50Ω
2001-04-12
CL
TEST
S1
tPLH, tPHL
Open
tPLZ, tPZL
Closed
tPHZ, tPZH
Open
Input Conditions
50Ω=Coax to
Oscilloscope
1. Input voltage = 0 V to 3.0 V
2. tr = tf = 2.5ns (10% to 90%)
Page 5
MDSS-0011-01
www.vaishali.com
Vaishali Semiconductor 747 Camden Avenue, Suite C Campbell CA 95008 Ph. 408.377.6060 Fax 408.377.6063
VS3125
Switching Waveforms
3.0 V
Input
1.5 V
0V
tPLH
tPHL
VOH
Switch Output
1.5 V
VOL
Propagation Delay
3.0 V
1.5 V
Control Input
0V
tPZH
tPHZ
VOH
0.3 V
Switch Output
(Switch Input = 3.0 V)
1.5 V
0V
tPLZ
Switch Output
(Switch Input = 0 V)
tPZL
0.3 V
Switch ON
Switch OFF
3.5 V
1.5 V
VOL
Switch ON
Enable and Disable Times
Ordering Information
Part Number
VS3125Q
2001-04-12
No. of Pins
16
Package
QSOP
Temperature
-40°C to +85°C
Page 6
MDSS-0011-01
www.vaishali.com
Vaishali Semiconductor 747 Camden Avenue, Suite C Campbell CA 95008 Ph. 408.377.6060 Fax 408.377.6063