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Details, datasheet, quote on part number:74FST3125
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Datasheet text preview:
IDT74FST3125 4-BIT BUS SWITCH
COMMERCIAL TEMPERATURE RANGE
4-BIT BUS SWITCH
IDT74FST3125
FEATURES:
- - - - - - Bus switches provide zero delay paths Extended commercial range of 40°C to +85°C Low switch on-resistance: FST3xxx 5 TTL-compatible input and output levels ESD > 2000V per MIL-STD-883, Method 3015; > 200V using machine model (C = 200pF, R = 0) Available in QSOP, SOIC, and TSSOP Packages
DESCRIPTION:
The FST3125 belong to IDT's family of Bus switches. Bus switch devices perform the function of connecting or isolating two ports without providing any inherent current sink or source capability. Thus they generate little or no noise of their own while providing a low resistance path for an external driver. These devices connect input and output ports through an n-channel FET. When the gate-to-source junction of this FET is adequately forwardbiased the device conducts and the resistance between input and output ports is small. Without adequate bias on the gate-to-source junction of the FET, the FET is turned off, therefore with no VCC applied, the device has hot insertion capability. The low on-resistance and simplicity of the connection between input and output ports reduces the delay in this path to close to zero. The FST3125 is a 4-bit TTL-compatible bus switch. The xOE pins provide individual enable control for each of the four bits.
FUNCTIONAL BLOCK DIAGRAM
1A 1O E 1Y
PIN CONFIGURATION
NC 1O E 1A 1Y 2O E 1 2 3 4 5 6 7 8 S O 1 6 -1 S O 1 6 -7 16 15 14 13 12 11 10 9 V cc 4O E 4A 4Y 3O E 3A 3Y NC
2A 2O E
2Y
2A 2Y GND
3A 3O E
3Y
SOIC/ QSOP TOP VIEW
1O E 1A
1 2 3 4 5 6 7 S O 1 4 -3
14 13 12 11 10 9 8
V cc 4O E 4A 4Y 3O E 3A 3Y
4A 4O E
4Y
1Y 2O E 2A 2Y GND
TSSOP TOP VIEW
COMMERCIAL TEMPERATURE RANGE
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c 1999 Integrated Device Technology, Inc.
AUGUST 1999
DSC-3471/4
IDT74FST3125 4-BIT BUS SWITCH
COMMERCIAL TEMPERATURE RANGE
ABSOLUTE MAXIMUM RATINGS(1)
Symbol VTERM(2) TSTG IOUT Rating Terminal Voltage with Respect to GND Storage Temperature Maximum Continuous Channel Current Commercial 0.5 to +7 65 to +150 128 Unit V °C mA
PIN DESCRIPTION
Pin Names 1A-4A 1Y-4Y NC 1OE, 4OE I/O I/O I/O -- I Description Bus A Bus B No Connect Bus Switch Enable (Active LOW)
NOTES: 1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. 2. Vcc, Control, and Switch terminals.
FUNCTION TABLE
OE H L Y Hi-Z A Description Disconnect Connect
CAPACITANCE
(1) Conditions(2) Switch Off Typ. 4 Unit
pF pF
Symbol Parameter CIN Control Input Capacitance CI/O Switch Input/Output Capacitance
NOTES: 1. Capacitance is characteriszed but not tested. 2. TA = 25°C, f = 1MHz, VIN = 0V, VOUT = 0V
DC ELECTRICAL CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified: Commercial: TA = -40°C to +85°C, VCC = 5.0V ± 5% Symbol VIH VIL IIH IIL IOZH IOZL IOS VIK RON Parameter Input HIGH Voltage Input LOW Voltage Input HIGH Current Input LOW Voltage High Impedance Output Current (3-State Output pins) Short Circuit Current Clamp Diode Voltage Switch On Resistance(4) VCC = Max., VO = GND(3) VCC = Min., IIN = 18mA VCC = Min. VIN = 0.0V ION = 30mA VCC = Min. VIN = 2.4V ION = 15mA IOFF ICC Input/Output Power Off Leakage Quiescent Power Supply Current VCC = 0V, VIN or VO = 4.5V VCC = Max., VIN = GND or VCC -- -- -- 0.1 ±1 3 µA µA -- 10 15 VCC = Max. Test Conditions(1) Guaranteed Logic HIGH for Control Inputs Guaranteed Logic LOW for Control Inputs VCC = Max. VI = VCC VI = GND VO = VCC VO = GND Min. 2 -- -- -- -- -- -- -- -- Typ.(2) -- -- -- -- -- -- 300 0.7 5 Max. -- 0.8 ±1 ±1 ±1 ±1 -- 1.2 7 mA V µA Unit V V µA
NOTES: 1. For conditions shown as Max. or Min., use appropriate value specified under Electrical Characteristics for the applicable device type. 2. Typical values are at Vcc = 5.0V, +25°C ambient. 3. Not more than one output should be tested at one time. Duration of the test should not exceed one second. 4. Measured by voltage drop between ports at indicated current through the switch.
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IDT74FST3125 4-BIT BUS SWITCH
COMMERCIAL TEMPERATURE RANGE
POWER SUPPLY CHARACTERISTICS
Symbol ICC ICCD Parameter Quiescent Power Supply Current TTL Inputs HIGH Dynamic Power Supply Current(4) Test Conditions(1) VCC = Max. VIN = 3.4V(3) VCC = Max. VIN = VCC Outputs Open VIN = GND Enable Pin Toggling 50% Duty Cycle VIN = VCC VCC = Max. Outputs Open VIN = GND Enable Pin Toggling VIN = 3.4 (4 Switches Toggling) fi = 10MHz VIN = GND 50% Duty Cycle Min. -- -- Typ.(2) 0.5 30 Max. 1.5 40 Unit mA µ A/ MHz/ Switch mA
IC
Total Power Supply Current(5)
--
1.2
1.6
--
1.5
2.4
NOTES: 1. For conditions shown as Max. or Min., use appropriate value specified under Electrical Characteristics for the applicable device type. 2. Typical values are at VCC = 5.0V, +25°C ambient. 3. Per TTL driven input (VIN = 3.4V). All other inputs at VCC or GND. 4. This parameter is not directly testable, but is derived for use in Total Power Supply Calculations. 5. IC = IQUIESCENT + IINPUTS + IDYNAMIC IC = ICC + ICC DHNT + ICCD (fiN) ICC = Quiescent Current ICC = Power Supply Current for a TTL High Input (VIN = 3.4V) DH = Duty Cycle for TTL Inputs High NT = Number of TTL Inputs at DH ICCD = Dynamic Current Caused by an Input Transition Pair (HLH or LHL) fi = Input Frequency N = Number of Switches Toggling at fi All currents are in milliamps and all frequencies are in megahertz.
SWITCHING CHARACTERISTICS OVER OPERATING RANGE
Following Conditions Apply Unless Otherwise Specified: Commercial: TA = -40°C to +85°C, VCC = 5.0V ± 5% Symbol tPLH tPHL tPZH tPZL tPHZ tPLZ |QCI| Description Data Propagation Delay A to Y, Y to A(3,4) Switch Turn on Delay OE to A, Y Switch Turn off Delay OE to A, Y(3) Charge Injection(5,6) Condition(1) CL = 50pF RL = 500 Min.(2) -- 1.5 1.5 -- Typ. -- -- -- 1.5 Max. 0.25 6.5 5.5 -- Unit ns ns ns pC
NOTES: 1. See test circuit and waveforms. 2. Minimum limits guaranteed but not tested. 3. This parameter is guaranteed by design but not tested. 4. The bus switch contributes no propagation delay other than the RC delay of the on resistance of the switch and the load capacitance. The time constant for the switch alone is of the order of 2.5ns for 50pF load. Since this time is constant and much smaller than the rise/fall times of typical driving signals, it adds very little propagation delay to the system. Propagation delay on the bus switch when used in a system is determined by the driving circuit on the driving side of the switch and its interaction with the load on the driven side. 5. Measured at switch turn off, load = 50 pF in parallel with 10M scope probe, VIN = 0.0 volts. 6. Characterized parameter. Not 100% tested.
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IDT74FST3125 4-BIT BUS SWITCH
COMMERCIAL TEMPERATURE RANGE
TEST CIRCUITS AND WAVEFORMS TEST CIRCUITS FOR ALL OUTPUTS
V CC 5 0 0 V IN P u ls e G e n e r a to r D . U .T . 50pF R
T
SWITCH POSITION
Test Open Drain Disable Low Enable Low All Other Tests Open
8-link
7 .0 V
Switch Closed
V OUT
5 0 0
C
L
DEFINITIONS: CL = Load capacitance: includes jig and probe capacitance. RT = Termination resistance: should be equal to ZOUT of the Pulse Generator.
O c t a l lin k
SET-UP, HOLD, AND RELEASE TIMES
DATA IN P U T tS U T IM IN G INPUT ASYN CH R ON OUS C ON TROL PRESET CLEAR ETC. S Y N C H R O N O U S CONTRO L PRESET CLEAR C L O C K ENABLE ETC. tR E M tH 3V 1 .5 V 0V 3V 1 .5 V 0V 3V 1 .5 V 0V 3V 1 .5 V 0V
O c t a l lin k
PULSE WIDTH
L O W -H IG H - L O W PULSE tW H I G H - L O W - H IG H PULSE
O c t a l lin k
1 .5 V
1 .5 V
tS U
tH
PROPAGATION DELAY
S A M E PHASE I N P U T TRANSITION tP L H OUTPUT tP L H O P P O S IT E P H A S E I N P U T TRANSITION tP H L tP H L 3V 1 .5 V 0V V OH 1 .5 V V OL 3V 1 .5 V 0V
O c t a l lin k
ENABLE AND DISABLE TIMES
ENAB LE D IS A B L E 3V CO NTROL IN P U T tP Z L OUTPUT NO RM A LLY LO W S W IT C H CLOSED tP Z H OUTPUT NO RM A LLY H IG H S W IT C H OPEN 3 .5 V 1 .5 V 0 .3 V tP H Z 0 .3 V 1 .5 V 0V 0V
O c t a l lin k
1 .5 V tP L Z 0V 3 .5 V VOL V OH
NOTES: 1. Diagram shown for input Control Enable-LOW and input Control DisableHIGH 2. Pulse Generator for All Pulses: Rate 1.0MHz; tF 2.5ns; tR 2.5ns
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IDT74FST3125 4-BIT BUS SWITCH
COMMERCIAL TEMPERATURE RANGE
ORDERING INFORMATION
ID T XX T e m p . Range FST XX D e v ic e Type X P ackage
SO Q PG
S m a l l Outline IC (SO16-1) Q u a r t e r - s iz e Small Outline Package (SO16-7) T h in Shrink Small Outpine Package (SO14-3)
3125
4 - B it Bus Switch
74
- 4 0 ° C to +85°C
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*To search for sales office near you, please click the sales button found on our home page or dial the 800# above and press 2. The IDT logo is a registered trademark of Integrated Device Technology, Inc.
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