December 2011
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6
FSA1256(A) / FSA1257(A) / FSA1258(A) — Low-RON Low-Voltage, Dual SPDT Analog Switch with Low-ICCT “A” Option
FSA1256(A) / FSA1257(A) / FSA1258(A)
Low-RON Low-Voltage, Dual SPDT Analog Switch
with Low-ICCT “A” Option
Features
FSA1256A, FSA1257A, FSA1258A Feature Low
ICCT when S Input is Lower than VCC
Maximum 1.1 On Resistance (RON) for 4.5V
Supply
0.4 max RON Flatness for 4.5V Supply
Space-Saving Pb-Free MicroPak™ Packaging
Broad VCC Operating Range:
- FSA1256, FSA1257, FSA1258: 1.65V to 5.5V
- FSA1256A, FSA1257A, FSA1258A: 2.7V to 5.5V
Fast Turn-On and Turn-Off Times
FSA1258, FSA1258A Feature Break-Before-Make
Enable Circuitry
Over-Voltage Tolerant TTL-Compatible Control Input
Applications
Cell Phone, PDA, Digital Camera, and Notebook
LCD Monitor, TV, and Set-Top Box
Description
The FSA1256, FSA1256A, FSA1257, FSA1257A,
FSA1258, and FSA1258A are high performance dual
Single-Pole / Single-Throw (SPST) analog switches. All
devices feature ultra-low RON of 1.1 maximum at 4.5V
VCC. The FSA1256, FSA1257, and FSA1258 operate
over a wide VCC range of 1.65V to 5.5V. The FSA1256A,
FSA1257A, and FSA1258A operation range is 2.7V to
5.5V. These devices are fabricated with sub-micron
CMOS technology to achieve fast switching speeds and
are designed for break-before-make operation. The
select input is TTL level compatible. The FSA1256 and
FSA1256A feature two Normally Open (NO) switches.
The FSA1257 and FSA1257A feature two Normally
Closed (NC) switches. The FSA1258 and FSA1258A
have one NO switch and one NC switch.
IMPORTANT NOTE:
For additional performance information, please contact
analogswitch@fairchildsemi.com.
Ordering Information
Part Number Top Mark Package Description Packing Method
FSA1256L8X EB 8-Lead, MicroPak™, 1.6mm Wide 5000 Units Tape and Reel
FSA1256AL8X FN 8-Lead, MicroPak™, 1.6mm Wide 5000 Units Tape and Reel
FSA1257L8X EC 8-Lead, MicroPak™, 1.6mm Wide 5000 Units Tape and Reel
FSA1257AL8X FP 8-Lead, MicroPak™, 1.6mm Wide 5000 Units Tape and Reel
FSA1258L8X ED 8-Lead, MicroPak™, 1.6mm Wide 5000 Units Tape and Reel
FSA1258AL8X FS 8-Lead, MicroPak™, 1.6mm Wide 5000 Units Tape and Reel
MicroPak™ is a trademark of Fairchild Semiconductor Corporation.
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6 2
FSA6157 / FSA6157T — Low-RON SPDT (0.8
) Negative-Swing Audio or Video Switch
Analog Symbols
Figure 1. FSA1256, FSA1256A Figure 2. FSA1257, FSA1257A
Truth Tables
Control Input (s) Function Control Input (s) Function
LOW Logic Level Disconnect LOW Logic Level A Connected to B
HIGH Logic Level A Connected to B HIGH Logic Level Disconnected
4
3
2
1
5
6
7
81A
Vcc
1S
2B
2A
1B
2S
GND
Figure 3. FSA1258, FSA1258A
Truth Table
Control Input, 1S Function Control Input 2S Function
LOW Logic Level 1A Connected to 1 B LOW Logic Level Disconnect
HIGH Logic Level Disconnect HIGH Logic Level 2A Connected to 2B
Pin Descriptions
Name Description
A, B0, B1 Data Ports
S Switch Select Pin
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6 3
FSA6157 / FSA6157T — Low-RON SPDT (0.8
) Negative-Swing Audio or Video Switch
Absolute Maximum Ratings
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be
operable above the recommended operating conditions and stressing the parts to these levels is not recommended.
In addition, extended exposure to stresses above the recommended operating conditions may affect device reliability.
The absolute maximum ratings are stress ratings only.
Symbol Parameter Min. Max. Units
VCC Supply Voltage -0.5 6.0 V
VS Switch Voltage(1) -0.5 VCC +0.5 V
Vin Input Voltage(1) -0.5 6.0 V
Power Dissipation at 85C, MicroPak™ 8L Package 180 mW
IIK Input Diode Current -50 mA
ISW Switch Current 200 mA
ISWPEAK Peak Switch Current (Pulsed at 1ms Duration, <10% Duty Cycle) 400 mA
TSTG Storage Temperature Range -65 +150 C
TJ Maximum Junction Temperature +150 C
TL Lead Temperature (Soldering 10 Seconds) +260 C
ESD Human Body Model
(JEDEC: JESD22-A114)
FSA1256, FSA1257, FSA1258 5.5 kV
FSA1256A, FSA1257A, FSA1258A 4.5
Note:
1. Input and output negative ratings may be exceeded if input and output diode current ratings are observed.
Recommended Operating Conditions
The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended
operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not
recommend exceeding them or designing to absolute maximum ratings.
Symbol Parameter Min. Max. Units
VCC Supply Voltage FSA1256, FSA1257, FSA1258 1.65 5.50 V
FSA1256A, FSA1257A, FSA1258A 2.70 5.50
VIN Control Input Voltage(Error! Reference source not found.) 0 VCC V
VIN Switch Input Voltage 0 VCC V
ΘJA Thermal Resistance in Still Air, MicroPak 8L Package (Modeled) 224 °C/W
TA Operating Temperature -40 +85 ºC
Note:
2. Unused inputs must be held HIGH or LOW. They must not float.
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6 4
FSA6157 / FSA6157T — Low-RON SPDT (0.8
) Negative-Swing Audio or Video Switch
DC Electrical Characteristics
All typical values are at 25ºC unless otherwise specified. The 1.65V to 1.95V range applies to FSA1256, FSA1257,
and FSA1258 only.
Symbol Parameter Conditions VCC (V) TA=+25°C TA=-40 to
+85°C Unit
Min. Typ. Max. Min. Max.
VIH Input Voltage High(3)
4.5 to 5.5 2.4
V
2.7 to 3.6 2.0
1.65 to 1.95 0.9
VIL Input Voltage Low(3)
4.5 to 5.5 0.8
V
FSA1256A, FSA1257A,
FSA1258A Only 2.7 to 3.6 0.4
FSA1256, FSA1257,
FSA1258 Only
2.7 to 3.6 0.6
1.65 to 1.95 0.4
IIN Control Input Leakage
(S) VIN=0 to VCC 1.95 to 5.5 -1 1 µA
INO(0FF) ,
INC(0FF) Off Leakage Current A=1V, 4.5V
1B or 2B=1V, 4.5V 5.5 -2 2 -20 20 nA
RON Switch On
Resistance(3,4)
IOUT=100mA, 1B or
2B=3.5V 4.5 0.95 1.15 1.30
Ω
IOUT=100mA, 1B or
2B=1.5V 2.7 2.6 4.0 4.3
IOUT=100mA, 1B or
2B=1.2V 1.65 8.0 9.5 10.5
∆RON
On Resistance
Matching Between
Channels(3,5)
IOUT=100mA, 1B or
2B=3.5V 4.5 0.06 0.12 0.15 Ω
RFLAT(ON) On Resistance
Flatness(3,6)
IOUT=100mA, 1B or
2B=0V, 1.0V, 2.0V 4.5 0.2 0.3 0.4
Ω
IOUT=100mA, 1B or
2B=0V, 0.75V, 1.5V 2.7 1.4
IOUT=100mA, 1B or
2B=0V, 1.0V, 1.2V 1.65 1.8
ICC Quiescent Supply
Current VIN=0V or VCC, IOUT=0V 5.5 0.1 0.5 1.0
µA
3.6 0.1 0.5 1.0
ICCT Increase in Icc per Input
One Input at 2.6V,
Others at VCC or GND
(FSA1256A, FSA1257A,
FSA1258A Only)
4.3 0.2 10.0 µA
Notes:
3. Guaranteed, but not tested for Vcc=1.65V.
4. On resistance is determined by the voltage drop between A and B pins at the indicated current through the switch.
5. ∆ RON=RON max – RON min measured at identical VCC, temperature, and voltage.
6. Flatness is defined as the difference between the maximum and minimum value of on resistance (RON) over the
specified range of conditions.
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6 5
FSA6157 / FSA6157T — Low-RON SPDT (0.8
) Negative-Swing Audio or Video Switch
AC Electrical Characteristics
All typical values are at 25ºC unless otherwise specified. The 1.65V to 1.95V range applies to FSA1256, FSA1257,
and FSA1258 only.
Symbol Parameter Conditions VCC (V) TA=+25ºC TA=-40 to
+85°C Unit Figure
Min. Typ. Max. Min. Max.
tON Turn-On Time(7)
1B or 2B=3.0V,
RL=50Ω, CL=35pF 4.5 to 5.5 10 35 40
ns 8
1B or 2B=1.5V,
RL=50Ω, CL=35pF 2.7 to 3.6 15 50 60
1B or 2B=1.0V
RL=50Ω, CL=35pF
1.65 to
1.95 35 110 120
tOFF Turn-Off Time(7)
1B or 2B=3.0V,
RL=50Ω, CL=35pF 4.5 to 5.5 4 15 20
ns 8
1B or 2B=1.5V,
RL=50Ω, CL=35pF 2.7 to 3.6 8 20 30
1B or 2B=1.0V
RL=50Ω, CL=35pF
1.65 to
1.95 10 30 40
tBBM Break-Before-
Make Time(7)
1B or 2B=3.0V,
RL=50Ω, CL=35pF 4.5 to 5.5 7
ns 9
1B or 2B=1.5V,
RL=50Ω, CL=35pF 2.7 to 3.6 12
Q Charge
Injection(7)
CL=1.0nF,
VGEN=0V, RGEN=0Ω
4.5 to 5.5 20
pC 13
2.7 to 3.6 10
1.65 to
1.95 5
OIRR Off Isolation(7) f=1MHz, RL=50Ω, 1.65 to 5.5 -70 dB 11
Xtalk Crosstalk(7) f=1MHz, RL=50Ω, 1.65 to 4.3 -100 dB 12
BW -3db Bandwidth(7) R
L=50Ω 1.65 to 4.3 300 MHz 10
THD Total Harmonic
Distortion(7)
f=20Hz to 20kHz,
RL=600,
VIN=0.5VPP
1.65 to 4.3 0.002 % 16
Notes:
7. Guaranteed, but not tested for Vcc=1.65V.
Capacitance
Symbol Parameter Conditions VCC (V) TA=+25ºC Unit Figure
Min. Typ. Max.
CIN Control Pin Input Capacitance f=1MHz 0 3.0 pF 15
COFF B Port Off Capacitance f=1MHz 4.5 11.5 pF 14
CON A Port On Capacitance f=1MHz 4.5 27.0 pF 15
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6 6
FSA6157 / FSA6157T — Low-RON SPDT (0.8
) Negative-Swing Audio or Video Switch
Test Diagrams
Select
B0,B1
A
V
S
= 0 or V
CC
ION
VON
RON =V
ON /I
ON
GND
VSW
GND
V
Select
= 0 or V
cc
NC
A
I
A(OFF)
V
IN
GND
I
V
IN
V
IN
V
S
Figure 4. On Resistance Figure 5. Off Leakage (Po rts Tested Separately)
Selec
t
V
S
=0 orVcc
NC I
A(ON)
V
IN
GND
A
V
IN
V
R
L
C
L
nB
n
nA
GND
GND
R
S
V
Sel
V
IN
GND
V
OUT
Figure 6. On Leakage Figure 7. Test Circuit Load
t
RISE
=2.5ns
GND
V
CC
90% 90%
10%10%
t
FALL
= 2.5ns
V
CC
/2 V
CC
/2
Input - V
Sel
Output- V
OUT
90%
V
OH
V
OL
t
ON
t
OFF
90%
t
FALL
-
-
-
Figure 8. Turn-On / Turn-Off Waveforms
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6 7
FSA6157 / FSA6157T — Low-RON SPDT (0.8
) Negative-Swing Audio or Video Switch
Test Diagrams (Continued)
V
CC
V
CC
/2
tD
0V
V
OUT
Input -V
Sel
0.9*V
OUT
t
RISE
=2.5ns
90%
10%
C
L
B0 B1
n
R
L
nA
GND
GND
R
S
V
Sel
V
SW
GND
V
OUT
V
IN
GND
V
--
V
Sel
R
L
and C
L
are functions of the application
environment (50, 75, or 100 ).
C
L
includes test fixture and stray capacitance.
0.9*V
OUT
Figure 9. Break-Before-Make Interval Timing
V
OUT
GND
GND
R
T
GND
GND
V
S
R
S
Network Analyzer
V
S
GND
R
S
and R
T
are functions of the application
environment (50, 75, or 100 ).
V
IN
Figure 10. Bandwidth
V
OUT
GND
GND
R
T
GND
GND
V
S
R
S
Network Analyzer
R
T
GND
V
Sel
GND
Off Isolation= 20 Log (V
OUT
/
V
IN
)
T
R
S
and R
T
are functions of the application
environment (50, 75, or 100 ).
Figure 11. Channel Off Isolation
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6 8
FSA6157 / FSA6157T — Low-RON SPDT (0.8
) Negative-Swing Audio or Video Switch
Test Diagrams (Continued)
R
S
and R
T
are functions of the application
environment (50, 75, or 100 ).
V
OUT
GND
GND
R
T
GND
GND
V
S
R
S
Network Analyzer
R
T
GND
V
Sel
GND
Crosstalk = 20 Log (V
OUT
/ V
IN
)
V
IN
Figure 12. Adjacent Channel Cro sstalk
R
S
V
OUT
Q = V
OUT
• CL
V
OUT
V
OUT
V
CC
0V
Input – V
SEL
Generator
GND
V
S
C
L
VSEL
V
IN
B
nS
n
GND C
L
includes test fixture and stray capacitance
GND
Off On Off
mA
Figure 13. Charge Injection Test
B0nB1
Capacitance
Meter
Select
B0,B1
f=1MHz
V
S
= 0 or V
CC
nB
n
Capacitance
Meter
Select
f=1MHz V
S
= 0 or V
CC
nB
n
Figure 14. Channel Off Capacitance Figure 15. Channel On Capacitance
V
OUT
GND
GND R
T
GND
GND
V
S
R
S
Audio Analyzer
V
CNTRL
GND
V
IN
V
CNTRL
=0orVcc
R
S
and R
T
are functions of the
application environment.
Figure 16. Total Harmonic Distortion
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6 9
FSA6157 / FSA6157T — Low-RON SPDT (0.8
) Negative-Swing Audio or Video Switch
Physical Dimensions
(0.09)
(0.1)
(0.2)
1.6
2X
0.05
0.00
1.6
2X
C0.05 C
4
3. DRAWING CONFORMS TO ASME Y.14M-1994
2. DIMENSIONS ARE IN MILLIMETERS
1. PACKAGE CONFORMS TO JEDEC MO-255 VARIATION UAAD
BOTTOM VIEW
4. PIN 1 FLAG, END OF PACKAGE OFFSET
MAC08AREV4
123
567
8
Notes:
8X 0.25
0.35
3X
8X
1.0
4
0.5
8X
0.25
0.15
0.10 CAB
0.05 C
0.10 C
TOP VIEW
INDEX AREA
B
Recommended Landpattern
A
0.10 C
0.55 MAX
0.05 C
DETAIL A
0.35
0.25
(0.15)
(0.20)
0.35
0.25
DETAIL A
PIN #1 TERMINAL
SCALE: 2X
5. DRAWING FILE NAME: MKT-MAC08AREV4
Figure 17. 8-Lead MicroPak™, 1.6mm Wide
For tape and reel specifications for MicroPak, please visit:
http://www.fairchildsemi.com/products/logic/pdf/micropak_tr.pdf
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify or
obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions,
specifically the warranty therein, which covers Fairchild products.
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/.
© 2004 Fairchild Semiconductor Corporation www.fairchildsemi.com
FSA1256(A) / FSA1257(A) / FSA1258(A) Rev. 1.0.6 10
FSA6157 / FSA6157T — Low-RON SPDT (0.8
) Negative-Swing Audio or Video Switch
