INTEGRATED CIRCUITS
FBL2041
FBL2041I
3.3V BTL 7-bit Futurebus+ transceiver
(standard A-port)
Product specification
Supersedes data of 1998 May 11
IC23 Data Handbook
1999 Apr 27
Philips Semiconductors Product specification
3.3V BTL 7-bit Futurebus+ transceiver (standard A-port)
FEA TURES
• 7-bit BTL transceiver
• Separate I/O on TTL A-port
• Inverting
• Three separate pairs of driver enables in a 1 bit, 3 bit, 3 bit
arrangement
• Drives heavily loaded backplanes with equivalent load
impedances down to 10Ω.
• High drive 100mA BTL open collector drivers on B-port
• Allows incident wave switching in heavily loaded backplane buses
• Reduced BTL voltage swing produces less noise and reduces
power consumption
• Built-in precision band-gap reference provides accurate receiver
thresholds and improved noise immunity
• Compatible with IEEE Futurebus+ or proprietary BTL backplanes
• Controlled output ramp and multiple GND pins minimize ground
bounce
• Each BTL driver has a dedicated Bus GND for a signal return
• Glitch-free power up/power down operation
• Low I
current
CC
• Tight output skew
• Supports live insertion
• Pins for the optional JTAG boundary scan function are provided
• High density packaging in plastic Quad Flatpack
• 5V compatible I/O on A-port
• Industrial temperature range option available as FBL2041I
DESCRIPTION
The FBL2041/FBL2041I is a 7-bit bidirectional BTL transceiver and
is intended to provide the electrical interface to a high performance
wired-OR bus. The FBL2041 is an inverting transceiver.
The B-port drivers are Low-capacitance open collectors with
controlled ramp and are designed to sink 100mA. Precision band
gap references on the B-port insure very good noise margins by
limiting the switching threshold to a narrow region centered at 1.55V .
The FBL2041/FBL2041I is pin and function compatible with FB2041
but operates at a 3.3V supply voltage, greatly reducing power
consumption.
The B-port interfaces to “Backplane Transceiver Logic” (See the
IEEE 1194.1 BTL standard). BTL features low power consumption
by reducing voltage swing (1Vp-p, between 1V and 2V) and reduced
capacitive loading by placing an internal series diode on the drivers.
BTL also provides incident wave switching, a necessity for high
performance backplanes.
There are three separate pairs of driver enables in a 1 bit, 3 bit, 3 bit
arrangement. The TTL/BTL output drivers for bit 0 are enabled with
OEA1/OEB1
OEA2/OEB2
OEA3/OEB3
The A-port operates at TTL levels with separate I/O. The 3-state
A-port drivers are enabled when OEAn goes High after an extra 6ns
delay which is built in to provide a break-before-make function.
When OEAn goes Low, A-port drivers become High impedance
without any extra delay. During power on/of f cycles, the A-port
drivers are held in a High impedance state when V
The B-port has an output enable, OEB0, which affects all seven
drivers. When OEB0 is High and OEBn
be enabled. When OEB0 is Low or if OEBn
drivers will be inactive and at the level of the backplane signal.
To support live insertion, OEB0 is held Low during power on/off
cycles to insure glitch free B port drivers. Proper bias for B port
drivers during live insertion is provided by the BIAS V pin when at a
3.3V level while V
BIAS V pin should be tied to a V
The LOGIC GND and BUS GND pins are isolated in the package to
minimize noise coupling between the BTL and TTL sides. These
pins should be tied to a common ground external to the package.
Each BTL driver has an associated BUS GND pin that acts as a
signal return path and these BUS GND pins are internally isolated
from each other. In the event of a ground return fault, a “hard” signal
failure occurs instead of a pattern dependent error that may be very
infrequent and impossible to trouble-shoot.
JTAG boundary scan functionality is provided as an option with
signals TMS, TCK, TDI and TDO. When this option is not present,
TMS and TCK are no-connects (no bond wires) and TDI and TDO
are shorted together internally.
, output drivers for bits 1–2–3 are enabled with
and output drivers for bits 4–5–6 are enabled with
.
is Low. If live insertion is not a requirement, the
CC
FBL2041
FBL2041I
CC
is Low the output driver will
is High, the B-port
pin.
CC
is below 1.3V.
QUICK REFERENCE DATA
SYMBOL PARAMETER TYPICAL UNIT
t
PLH
t
PHL
t
PLH
t
PHL
C
I
OB
OL
pp
Propagation delay 4.2
AIn to Bn 3.5
Propagation delay 4.8
Bn to AOn 4.9
Output capacitance (B0 - B6 only) 6 pF
Output current (B0 - B6 only) 100 mA
Standby 5.2
AIn to Bn (outputs Low or High) 3.2
Bn to AOn (outputs Low) 13.5
Bn to AOn (outputs High) 10.7
ORDERING INFORMATION
PACKAGE
52-pin Plastic Quad Flatpack FBL2041 BB FBL2041I BB SOT379-1
1999 Apr 27 853-2040 21374
COMMERCIAL RANGE
VCC = 3.3V±10%; T
= 0 to +70°C
amb
VCC = 3.3V±10%; T
2
INDUSTRIAL RANGE
= –40 to +85°C
amb
DWG
No.
Philips Semiconductors Product specification
3.3V BTL 7-bit Futurebus+ transceiver (standard A-port)
PIN CONFIGURATION
LOGIC GND
AI2
AO2
LOGIC GND
AO3
LOGIC GND
AI4
AO4
LOGIC GND
AO5
LOGIC GND
AI1
AI3
CC
AI0
AO1
52 51 50 49 48 47 46 45 44 43 42 41 40
1
2
3
4
5
6
7
8
9
10
11
12
13
14 15 16 17 18 19 20 21 22 23 24 25 26
AI5
LOGIC GND
BIAS V
AO0
LOGIC V
OEA1
OEB0
7-Bit Transceiver
52-lead PQFP
CC
AI6
AO6
LOGIC V
OEA2
LOGIC GND
CC
OEB1
TCK (option)
BUS V
CC
BUS V
TDI (option)
TDO (option)
TMS (option)
BUS GND
OEB2
OEA3
B0
39
38
37
36
35
34
33
32
31
30
29
28
27
OEB3
FBL2041
FBL2041I
BUS GND
B1
BUS GND
B2
BUS GND
B3
BUS GND
B4
BUS GND
B5
BUS GND
B6
N/C
SG00115
PIN DESCRIPTION
SYMBOL PIN NUMBER TYPE NAME AND FUNCTION
AI0 – AI6 51, 2, 3, 8, 9, 14, 18 Input Data inputs (TTL)
AO0 – AO6 50, 52, 4, 6, 10, 12, 16 Output 3-State outputs (TTL)
B0 – B6 40, 38, 36, 34, 32, 30, 28 I/O Data inputs/Open Collector outputs, High current drive (BTL)
OEB0 46 Input Enables the Bn outputs when High
OEB1 45 Input Enables the B0 output when Low
OEB2 25 Input Enables the B1 – B3 outputs when Low
OEB3 26 Input Enables the B4 – B6 outputs when Low
OEA1 47 Input Enables the A0 outputs when High
OEA2 20 Input Enables the A1 – A3 outputs when High
OEA3 24 Input Enables the A4 – A6 outputs when High
BUS GND 41, 39, 37, 35, 33, 31, 29 GND Bus ground (0V)
LOGIC GND 1, 5, 7, 11, 13, 15, 19 GND Logic ground (0V)
BUS V
CC
LOGIC V
CC
BIAS V 48 Power Positive supply voltage
TMS 42 Input Test Mode Select (no-connect)
TCK 44 Input Test Clock (no-connect)
TDI 22 Input Test Data In (shorted to TDO)
TDO 21 Output Test Data Out (TDI)
N/C 27 — Not connected
23, 43 Power Positive supply voltage
17, 49 Power Positive supply voltage BAND GAP
1999 Apr 27
3
Philips Semiconductors Product specification
3.3V BTL 7-bit Futurebus+ transceiver (standard A-port)
FBL2041
FBL2041I
FUNCTION TABLE
INPUTS OUTPUTS
AIn Bn* OEB0 OEB1 OEB2 OEB3 OEA1 OEA2 OEA3 AOn Bn*
L — H L L L L L L Z H**
AIn to Bn H — H L L L L L L Z L
L — H L L L H H H L H**
H — H L L L H H H H L
L — H L X X L L L Z H**
AI0 to B0 H — H L X X L L L Z L
L — H L X X H H H L H**
H — H L X X H H H H L
L — H X L X L L L Z H**
AI1 – AI3 to B1 – B3 H — H X L X L L L Z L
L — H X L X H H H L H**
H — H X L X H H H H L
L — H X X L L L L Z H**
AI4 – AI6 to B4 – B6 H — H X X L L L L Z L
L — H X X L H H H L H**
H — H X X L H H H H L
Disable Bn outputs X X L X X X X X X X H**
X X X H H H X X X X H**
Disable B0 outputs X X H H X X X X X X H**
Disable B1 – B3 outputs X X H X H X X X X X H**
Disable B4 – B6 outputs X X H X X H X X X X H**
X L L X X X H H H H Input
Bn to AOn X H L X X X H H H L Input
X L X H H H H H H H Input
X H X H H H H H H L Input
X L L X X X H X X H Input
B0 to AO0 X H L X X X H X X L Input
X L X H H H H X X H Input
X H X H H H H X X L Input
X L L X X X X H X H Input
B1 – B3 to AO1 – AO3 X H L X X X X H X L Input
X L X H H H X H X H Input
X H X H H H X H X L Input
X L L X X X X X H H Input
B4 – B6 to AO4 – AO6 X H L X X X X X H L Input
X L X H H H X X H H Input
X H X H H H X X H L Input
Disable AOn outputs X X X X X X L L L Z X
Disable AO0 outputs X X X X X X L X X Z X
Disable AO1 – AO3 outputs X X X X X X X L X Z X
Disable AO4 – AO6 outputs X X X X X X X X L Z X
NOTES:
H = High voltage level
L = Low voltage level
X = Don’t care
Z = High-impedance (OFF) state
— = Input not externally driven
H** = Goes to level of pull-up voltage
B* = Precaution should be taken to ensure B inputs do not float. If they do, they are equal to Low state.
1999 Apr 27
4