SN74CBTD3305C
DUAL FET BUS SWITCH WITH LEVEL SHIFTING
5-V BUS SWITCH WITH –2-V UNDERSHOOT PROTECTION
SCDS126A − SEPTEMBER 2003 − REVISED OCTOBER 2003
D Undershoot Protection for Off-Isolation on
D Data I/Os Support 0 to 5-V Signaling Levels
A and B Ports Up To −2 V
Integrated Diode to VCC Provides 5-V Input
Down To 3.3-V Output Level Shift
Bidirectional Data Flow, With Near-Zero
Propagation Delay
Low ON-State Resistance (ron)
Characteristics (ron = 3 Ω Typical)
Low Input/Output Capacitance Minimizes
Loading and Signal Distortion
(Cio(OFF) = 5 pF Typical)
Data and Control Inputs Provide
Undershoot Clamp Diodes
VCC Operating Range From 4.5 V to 5.5 V
(0.8-V, 1.2-V, 1.5-V, 1.8-V, 2.5-V, 3.3-V, 5-V)
Control Inputs Can be Driven by TTL or
5-V/3.3-V CMOS Outputs
Ioff Supports Partial-Power-Down Mode
Operation
Latch-Up Performance Exceeds 100 mA Per
JESD 78, Class II
ESD Performance Tested Per JESD 22
− 2000-V Human-Body Model
(A114-B, Class II)
− 1000-V Charged-Device Model (C101)
Supports Both Digital and Analog
Applications: USB Interface, Memory
Interleaving, Bus Isolation, Low-Distortion
Signal Gating
D
D
D
D
D
D
D
D
D
D
D
D OR PW PACKAGE
(TOP VIEW)
1OE
1A
1B
GND
1
8
2
7
3
6
4
5
VCC
2OE
2B
2A
description/ordering information
The SN74CBTD3305C is a high-speed TTL-compatible FET bus switch with low ON-state resistance (ron),
allowing for minimal propagation delay. This device features an integrated diode in series with VCC to provide
level shifting for 5-V input down to 3.3-V output levels. Active Undershoot-Protection Circuitry on the A and B
ports of the SN74CBTD3305C provides protection for undershoot up to −2 V by sensing an undershoot event
and ensuring that the switch remains in the proper OFF state.
The SN74CBTD3305C is organized as two 1-bit bus switches with separate output-enable (1OE, 2OE) inputs.
It can be used as two 1-bit bus switches or as one 2-bit bus switch. When OE is high, the associated 1-bit bus
switch is ON, and the A port is connected to the B port, allowing bidirectional data flow between ports. When
OE is low, the associated 1-bit bus switch is OFF, and a high-impedance state exists between the A and B ports.
ORDERING INFORMATION
SOIC − D
−40°C
40°C to 85°C
TSSOP − PW
†
ORDERABLE
PART NUMBER
PACKAGE†
TA
TOP-SIDE
MARKING
Tube
SN74CBTD3305CD
Tape and reel
SN74CBTD3305CDR
Tube
SN74CBTD3305CPW
Tape and reel
SN74CBTD3305CPWR
CC305C
CC305C
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines
are available at www.ti.com/sc/package.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Copyright © 2003, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
SN74CBTD3305C
DUAL FET BUS SWITCH WITH LEVEL SHIFTING
5-V BUS SWITCH WITH –2-V UNDERSHOOT PROTECTION
SCDS126A − SEPTEMBER 2003 − REVISED OCTOBER 2003
description/ordering information (continued)
This device is fully specified for partial-power-down applications using Ioff. The Ioff feature ensures that
damaging current will not backflow through the device when it is powered down. The device has isolation during
power off.
To ensure the high-impedance state during power up or power down, OE should be tied to GND through a
pulldown resistor; the minimum value of the resistor is determined by the current-sourcing capability of the
driver.
FUNCTION TABLE
(each bus switch)
INPUT
OE
INPUT/OUTPUT
A
FUNCTION
H
B
A port = B port
L
Z
Disconnect
logic diagram (positive logic)
3
2
1A
1OE
1B
SW
1
5
6
2A
SW
2B
7
2OE
simplified schematic, each FET switch (SW)
A
B
Undershoot
Protection Circuit
EN†
†
2
EN is the internal enable signal applied to the switch.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN74CBTD3305C
DUAL FET BUS SWITCH WITH LEVEL SHIFTING
5-V BUS SWITCH WITH –2-V UNDERSHOOT PROTECTION
SCDS126A − SEPTEMBER 2003 − REVISED OCTOBER 2003
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V
Control input voltage range, VIN (see Notes 1 and 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V
Switch I/O voltage range, VI/O (see Notes 1, 2, and 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V
Control input clamp current, IIK (VIN < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −50 mA
I/O port clamp current, II/OK (VI/O < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −50 mA
ON-state switch current, II/O (see Note 4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±128 mA
Continuous current through VCC or GND terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±100 mA
Package thermal impedance, θJA (see Note 5): D package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97°C/W
PW package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149°C/W
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
†
Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. All voltages are with respect to ground unless otherwise specified.
2. The input and output voltage ratings may be exceeded if the input and output clamp-current ratings are observed.
3. VI and VO are used to denote specific conditions for VI/O.
4. II and IO are used to denote specific conditions for II/O.
5. The package thermal impedance is calculated in accordance with JESD 51-7.
recommended operating conditions (see Notes 6 and 7)
MIN
MAX
4.5
5.5
V
High-level control input voltage
2
5.5
V
Low-level control input voltage
0
0.8
V
VI/O
Data input/output voltage
0
5.5
V
TA
Operating free-air temperature
−40
85
°C
VCC
Supply voltage
VIH
VIL
UNIT
NOTES: 6. All unused control inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application
report, Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
7. In applications with fast edge rates, multiple outputs switching, and operating at high frequencies, the output may have little or no
level-shifting effect.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
3
SN74CBTD3305C
DUAL FET BUS SWITCH WITH LEVEL SHIFTING
5-V BUS SWITCH WITH –2-V UNDERSHOOT PROTECTION
SCDS126A − SEPTEMBER 2003 − REVISED OCTOBER 2003
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
TEST CONDITIONS
VIK
Control inputs
VCC = 4.5 V,
IIN = −18 mA
VIKU
Data inputs
VCC = 5 V,
0 mA > II ≥ −50 mA,
VIN = VCC or GND,
VOH
MIN
TYP†
Switch OFF
MAX
UNIT
−1.8
V
−2
V
±1
μA
±10
μA
See Figures 4 and 5
IIN
Control inputs
VCC = 5.5 V,
VIN = VCC or GND
IOZ‡
VCC = 5.5 V,
VO = 0 to 5.5 V,
VI = 0,
Switch OFF,
VIN = VCC or GND
Ioff
VCC = 0,
VO = 0 to 5.5 V,
VI = 0
10
μA
VCC = 5.5 V,
II/O = 0,
VIN = VCC or GND,
Switch ON or OFF
1.5
mA
One input at 3.4 V,
Other inputs at VCC or GND
2.5
mA
ICC
ΔICC§
Control inputs
VCC = 5.5 V,
Cin
Control inputs
VIN = 3 V or 0
3.5
pF
Cio(OFF)
VI/O = 3 V or 0,
Switch OFF,
VIN = VCC or GND
5
pF
Cio(ON)
VI/O = 3 V or 0,
Switch ON,
VIN = VCC or GND
12.5
pF
ron¶
VCC = 4.5 V
VI = 0
VI = 2.4 V,
IO = 64 mA
3
6
IO = 30 mA
3
6
IO = −15 mA
8
20
Ω
VIN and IIN refer to control inputs. VI, VO, II, and IO refer to data pins.
† All typical values are at V
CC = 5 V (unless otherwise noted), TA = 25°C.
‡ For I/O ports, the parameter I
OZ includes the input leakage current.
§ This is the increase in supply current for each input that is at the specified voltage level, rather than V
CC or GND.
¶ Measured by the voltage drop between the A and B terminals at the indicated current through the switch. ON-state resistance is determined by
the lower of the voltages of the two (A or B) terminals.
switching characteristics over recommended operating free-air temperature range (unless
otherwise noted) (see Figure 3)
PARAMETER
tpd#
#
4
FROM
(INPUT)
TO
(OUTPUT)
VCC = 5 V
± 0.5 V
MIN
UNIT
MAX
A or B
B or A
0.15
ns
ten
OE
A or B
1.5
4.7
ns
tdis
OE
A or B
1.5
5.3
ns
The propagation delay is the calculated RC time constant of the typical ON-state resistance of the switch and the specified load capacitance,
when driven by an ideal voltage source (zero output impedance).
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN74CBTD3305C
DUAL FET BUS SWITCH WITH LEVEL SHIFTING
5-V BUS SWITCH WITH –2-V UNDERSHOOT PROTECTION
SCDS126A − SEPTEMBER 2003 − REVISED OCTOBER 2003
undershoot characteristics (see Figures 1 and 2)
PARAMETER
TEST CONDITIONS
VOUTU
†
VCC = 5.5 V,
Switch OFF,
MIN
TYP†
2
VOH−0.3
VIN = VCC or GND
MAX
UNIT
V
All typical values are at VCC = 5 V (unless otherwise noted), TA = 25°C.
VCC
Input
Generator
Input
(Open
Socket)
100 kΩ
50 Ω
Ax
VS
11 V
DUT
Bx
100 kΩ
90 %
2 ns
10 %
−2 V
20 ns
Output
(VOUTU)
POST OFFICE BOX 655303
5.5 V
2 ns
10 %
10 pF
Figure 1. Device Test Setup
90 %
VOH
VOH − 0.3
Figure 2. Transient Input Voltage (VI) and Output
Voltage (VOUTU) Waveforms
(Switch OFF)
• DALLAS, TEXAS 75265
5
SN74CBTD3305C
DUAL FET BUS SWITCH WITH LEVEL SHIFTING
5-V BUS SWITCH WITH –2-V UNDERSHOOT PROTECTION
SCDS126A − SEPTEMBER 2003 − REVISED OCTOBER 2003
PARAMETER MEASUREMENT INFORMATION
FOR LEVEL SHIFTER
VCC
Input Generator
VIN
50 Ω
50 Ω
VG1
TEST CIRCUIT
DUT
7V
Input Generator
VI
S1
RL
VO
GND
50 Ω
50 Ω
VG2
CL
(see Note A)
RL
VCC
S1
RL
VI
CL
tpd(s)
5 V ± 0.5 V
Open
500 Ω
VCC or GND
50 pF
tPLZ/tPZL
5 V ± 0.5 V
7V
500 Ω
GND
50 pF
0.3 V
tPHZ/tPZH
5 V ± 0.5 V
Open
500 Ω
VCC
50 pF
0.3 V
TEST
Output
Control
(VIN)
VΔ
3V
1.5 V
3V
1.5 V
1.5 V
0V
tPLH
VOH
Output
1.5 V
Output
Waveform 1
S1 at 7 V
(see Note B)
tPLZ
3.5 V
1.5 V
tPZH
tPHL
1.5 V
VOL
1.5 V
0V
tPZL
Output
Control
(VIN)
Open
Output
Waveform 2
S1 at Open
(see Note B)
VOL + VΔ
VOL
tPHZ
VOH
1.5 V
VOH − VΔ
0V
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES (tpd(s))
NOTES: A. CL includes probe and jig capacitance.
B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.
Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.
C. All input pulses are supplied by generators having the following characteristics: PRR ≤ 10 MHz, ZO = 50 Ω, tr ≤ 2.5 ns, tf ≤ 2.5 ns.
D. The outputs are measured one at a time with one transition per measurement.
E. tPLZ and tPHZ are the same as tdis.
F. tPZL and tPZH are the same as ten.
G. tPLH and tPHL are the same as tpd(s). The tpd propagation delay is the calculated RC time constant of the typical ON-state
resistance of the switch and the specified load capacitance, when driven by an ideal voltage source (zero output impedance).
H. All parameters and waveforms are not applicable to all devices.
Figure 3. Test Circuit and Voltage Waveforms
6
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN74CBTD3305C
DUAL FET BUS SWITCH WITH LEVEL SHIFTING
5-V BUS SWITCH WITH –2-V UNDERSHOOT PROTECTION
SCDS126A − SEPTEMBER 2003 − REVISED OCTOBER 2003
TYPICAL CHARACTERISTICS
OUTPUT VOLTAGE HIGH
vs
SUPPLY VOLTAGE
OUTPUT VOLTAGE HIGH
vs
SUPPLY VOLTAGE
4
3.25
100 μA
6 mA
12 mA
3.5
100 μA
3.25
6 mA
12 mA
3
24 mA
24 mA
3
2.75
2.5
2.25
2
1.75
1.5
4.5
TA = 25°C
VI = VCC
3.75
VOH − Output Voltage High − V
3.5
2.75
2.5
2.25
2
1.75
4.75
5
5.25
5.5
1.5
4.5
5.75
4.75
VCC − Supply Voltage − V
5
5.25
5.5
5.75
VCC − Supply Voltage − V
OUTPUT VOLTAGE HIGH
vs
SUPPLY VOLTAGE
4
TA = 0°C
VI = VCC
3.75
VOH − Output Voltage High − V
VOH − Output Voltage High − V
3.75
4
TA = 85°C
VI = VCC
3.5
100 μA
3.25
6 mA
12 mA
3
24 mA
2.75
2.5
2.25
2
1.75
1.5
4.5
4.75
5
5.25
5.5
5.75
VCC − Supply Voltage − V
Figure 4. VOH Values
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
7
SN74CBTD3305C
DUAL FET BUS SWITCH WITH LEVEL SHIFTING
5-V BUS SWITCH WITH –2-V UNDERSHOOT PROTECTION
SCDS126A − SEPTEMBER 2003 − REVISED OCTOBER 2003
TYPICAL CHARACTERISTICS (continued)
OUTPUT VOLTAGE
vs
INPUT VOLTAGE
3.5
VCC = 5 V
TA = 25°C
VO − Output Voltage − V
3
100 μA
6 mA
12 mA
24 mA
2.5
2
1.5
1
5
0
0
1
2
3
4
5
VI − Input Voltage − V
Figure 5. Data Output Voltage vs Data Input Voltage
8
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
PACKAGE OPTION ADDENDUM
www.ti.com
19-Jan-2022
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
SN74CBTD3305CD
ACTIVE
SOIC
D
8
75
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 85
CC305C
SN74CBTD3305CDR
ACTIVE
SOIC
D
8
2500
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 85
CC305C
SN74CBTD3305CPWR
ACTIVE
TSSOP
PW
8
2000
RoHS & Green
NIPDAU | SN
Level-1-260C-UNLIM
-40 to 85
CC305C
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of