ROHM BH9595

Mulimedia ICs
SCSI active terminator
BH9595FP-Y / BH9596FP-Y
These SCSI active terminators, developed as a substitute for conventional discrete terminators, maintain good consistency between VM level (2.85V) and GND level (0V) and between VM level and VDD level, and have extremely
low power consumption, dropping to a maximum of 90 milliwatts at standby (compared to the maximum of 990 milliwatts used by conventional resistance terminators). These SCSI active terminators electrically control SCSI lines,
connecting and disengaging the terminating resistor by electrically controlling the enable pin. (The enable pin is
enabled at the HIGH level and switched to the High-Z state by the LOW level in the BH9595 and by the HIGH level in
the BH9596, completely disconnecting the SCSI line from the SCSI terminator.)
These SCSI active terminators allow for the configuration of flexible, energy-saving SCSI networks, and are ideal for
notebook computers, hard disk drives and a wide range of other products with SCSI capabilities.
Applications
•Compact
disk drives, optical disk drives, CD-ROM drives, tape drives, personal computers (including laptop
computers and notebook computers), workstations,
mainframes, laser printers, plotters
•1)Features
Internal 2.85V power supply and push-pull operation, for good consistency at all signal levels.
2) Enable pin for terminator enabling and disconnecting, facilitating SCSI network construction.
3) Low power consumption, ideal for energy-saving
systems.
Power consumption during standby : 90mW (compared to 990mW for conventional resistor terminators)Power consumption at 25% duty : 614mW
(compared to 1,360mW for convention resistor terminators)Significant reductions in power consumption are possible.
4) Wide operating range.
TERM power : 4.0 ~ 5.5V (Transient : 6.0V)
5) Thin, microminiature design, ideal for space-saving
applications.
Package body size : 13.6 × 5.4 × 1.9mm
6) Active termination of 18-line SCSI.
7) Internal thermal shutdown circuit.
8) Compatibility with SCSI-I and SCSI-II.
1
Mulimedia ICs
BH9595FP-Y / BH9596FP-Y
•Absolute maximum ratings (Ta = 25°C)
Symbol
Limits
Unit
Power supply voltage
Parameter
VDD1
– 0.3 ~ + 7.0
V
DC Output current ∗1
ISLD
– 30
mA
DC Output current ∗2
ISLS
35
mA
Input voltage
Vi
Power dissipation ∗3
Pd
V
– 0.6 ~ (VDD1 + 0.6)
Operating temperature
Topr
Storage temperature
Tstg
1.45
W
0 ~ + 75
°C
°C
– 55 ~ + 125
∗1 Drain Current (from Module to SCSI Line) / Line
∗2 Sink Current (from SCSI Line to Module) / Line
∗3 When mounted to a 90 × 50 × 1.6 mm glass epoxy board
•Recommended operating conditions (Ta = 25°C)
Parameter
Symbol
Min.
Typ.
Max.
Unit
V
VDD1
4.0
4.5
5.5∗
Input voltage
VIH
VDD1 – 0.6
—
VDD1 + 0.6
V
Input voltage
VIL
– 0.3
—
0.8
V
VSLX
– 0.3
—
VDD1 + 0.3
V
Power supply voltage
SCSI Line voltage
∗ Transient
6V
•Block diagram
∗
Not to be used
(N.C.)
“H”: ENABLE
“L”: DISCONNECT
EN
1
TSD
2
MODE
CONTROL
SCSI LINE 15 3
SCSI LINE 16 4
25 TSD
POW
23 SCSI LINE 14
to SW
POW
POW
SCSI LINE 18 6
20 SCSI LINE 11
POW
(PUSH - PULL)
POW
(PUSH - PULL)
GND
GND
110Ω
Resistors
SCSI LINE 1 8
SCSI LINE 2 9
19 SCSI LINE 10
POW
(PUSH - PULL)
POW
(PUSH - PULL)
SCSI LINE 3 10
SCSI LINE 4 11
(PUSH - PULL)
2.85V SUPPLY
SCSI LINE 5 12
VDD1 13
22 SCSI LINE 13
21 SCSI LINE 12
SCSI LINE 17 5
GND 7
24 VM
POW
2.85V GENERATER
POW
(PUSH - PULL)
BH9595FP-Y
18 SCSI LINE
9
17 SCSI LINE
8
16 SCSI LINE
7
15 SCSI LINE
6
14 VDD1
(TRMPWR)
Schottky barrier diodes
SYSTEM POWER
5.0V
0.1µ
2
+
2.2µ
–
For BH9596
∗“L”:
ENABLE
“H”: DISCONNECT
Mulimedia ICs
BH9595FP-Y / BH9596FP-Y
•Pin descriptions
Pin No.
Pin name
Pin No.
Pin name
1
(N.C.) Not to be used
14
VDD1
2
EN (Output enable)
15
SCSI Line 6
3
SCSI Line 15
16
SCSI Line 7
4
SCSI Line 16
17
SCSI Line 8
5
SCSI Line 17
18
SCSI Line 9
6
SCSI Line 18
19
SCSI Line 10
—
GND
—
GND
7
GND
20
SCSI Line 11
8
SCSI Line 1
21
SCSI Line 12
9
SCSI Line 2
22
SCSI Line 13
10
SCSI Line 3
23
SCSI Line 14
11
SCSI Line 4
24
VM
12
SCSI Line 5
25
TSD (TSD signal output)
13
VDD1
characteristics
•DCElectrical
characteristics (unless otherwise noted, Ta = 25°C)
Parameter
Input leakage current
Symbol
Min.
Typ.
Max.
Unit
IIL
50
110
200
µA
Conditions
Vi = GND, VDD1 = 5.5V
IIH
–1
—
1
µA
Vi = VDD1, VDD1 = 5.5V
SCSI line leakage current
ISLZ
–1
—
1
µA
EN = ENABLE∗4, VDD1 = 5.5V
SCSI line short current ∗1
ISLD
15
25
30
mA
EN = DISABLE∗5, SCSI Line = GND,
4.0 ⬉ VDD1 ⬉ 5.5V
SCSI line short current ∗2
ISLS
7
20
30
mA
EN = DISABLE∗5, SCSI Line = VDD1
4.0 ⬉ VDD1 ⬉ 5.5V
VM voltage
VM
2.700
2.85
3.000
V
IDDSTB
—
1.0
2.0
mA
EN = ENABLE∗4, 4.0V ⬉ VDD1 ⬉ 5.5V
SCSI total sink current
ISLS
300
—
550
mA
EN = DISABLE∗5, 18 SCSI Line = GND
4.0 ⬉ VDD1 ⬉ 5.5V
SCSI total drain current
ISLD
300
—
550
mA
EN = DISABLE∗5, 18 SCSI Line = VDD1
4.0 ⬉ VDD1 ⬉ 5.5V
SCSI equivalent resistance
RSL
105
—
115
Ω
EN = DISABLE∗5, SCSI Line: VDD1 = 4.7V
Pin capacity ∗3
PC
—
5.0
6.0
pF
EN = ENABLE∗4
Standby current ∗1
4.0 ⬉ VDD1 ⬉ 5.5V
∗1 Drain Current (from Module to SCSI Line) / Line
∗2 Sink Current (from SCSI Line to Module) / Line
∗3 Guaranteed performance
∗4 BH9595FP-Y: EN = GND, BH9595FP-Y: EN = VDD1
∗5 BH9696FP-Y: EN = VDD1, BH9696FP-Y: EN = GND
3
Mulimedia ICs
BH9595FP-Y / BH9596FP-Y
Transient characteristics (unless otherwise noted, Ta = 25°C)
Parameter
Symbol
Load Transient Voltage
2.85V→GND
∆VMTD1
Load Transient 1 / 10 decay Time
2.85V→GND
Min.
∆VMTD2
Load Transient 1 / 10 decay Time
GND→2.85V
∆VMTS1
Load Transient Voltage
2.85V→VDD1
τTS1
Load Transient Voltage
VDD1→2.85V
∆VMTS2
Load Transient Voltage
VDD1→2.85V
τTS2
Conditions
EN = DISABLE∗, 4.0 ⬉ VDD1 ⬉ 5.5V
100
mV
—
100
µs
EN = DISABLE∗, 4.0 ⬉ VDD1 ⬉ 5.5V
All SCSI Lines: 2.85V→GND Level
– 100
100
mV
EN = DISABLE∗, 4.0 ⬉ VDD1 ⬉ 5.5V
All SCSI Lines: GND→2.85V Level
—
100
µs
EN = DISABLE∗, 4.0 ⬉ VDD1 ⬉ 5.5V
All SCSI Lines: GND→2.85V Level
– 100
100
mV
EN = DISABLE∗, 4.0 ⬉ VDD1 ⬉ 5.5V
All SCSI Lines: 2.85V→VDD1 Level
—
100
µs
EN = DISABLE∗, 4.0 ⬉ VDD1 ⬉ 5.5V
All SCSI Lines: 2.85V→VDD1 Level
– 100
100
mV
EN = DISABLE∗, 4.0 ⬉ VDD1 ⬉ 5.5V
All SCSI Lines: VDD1→2.85V Level
—
100
µs
EN = DISABLE∗, 4.0 ⬉ VDD1 ⬉ 5.5V
All SCSI Lines: VDD1→2.85V Level
τTD2
Load Transient Voltage
2.85V→VDD1
Unit
– 100
τTD1
Load Transient Voltage
GND→2.85V
Max.
All SCSI Lines: 2.85V→GND Level
∗ BH9595FP-Y: EN = VDD1, BH9596FP-Y: GND
The transient characteristics are guaranteed design values.
SCSI
Line
Potential
VDD1 Level
2.85V
GND Level
– 5.5V
– 2.85V
0 V
tτ = 50ns
∆VMTD1
∆VMTS1
∆VMTD2
∆VMTS2
VM
τ
TD1
τ
τ
TD2
TS1
τ
TS1
SCSI Line
#1
VDD1
SCSI
Active
Terminator
+
+
#18
Same Voltage
as VDD1
–
–
VM
Fig. 1 Measurement of transient characteristics
4
Mulimedia ICs
BH9595FP-Y / BH9596FP-Y
•Application example
System
Power
System
Power
TERMPWR Line
SCSI Line
SCSI Line
#1
#1
SCSI DATA LINES
+
2.2µ
+
2.2µ
–
–
VDD1
VDD1
SCSI
Active
Terminator
SCSI
Active
Terminator
EN
#18
#18
EN
GND
GND
VM
VM
Fig. 2
5
Mulimedia ICs
BH9595FP-Y / BH9596FP-Y
•Thermal reduction curve
Mode
BH9595FP - Y
BH9596FP - Y
Disable
L
H
Enable
H
L
2.5
POWER DISSIPATION: P (W)
•Mode selection table
shutdown
•(1)Thermal
All outputs are opened at 175°C (typically).
(2) Temperature hysteresis is approximately 20°C.
(3) Thermal shutdown output table
1.45W
Duty64%
1.00
0.50
0
Level
Conditions
1.50
25
50
75
100
125
150
175
AMBIENT TEMPERATURE: Ta (°C)
Normal
“Low”
Shutdown
“High”
Fig. 3
notes
•(1)Operation
This terminator's operational range includes harmonic frequencies. Mount to minimize ground
impedance.
(2) Connect the VDD1 pin (TERMPWR) to a grounded
2.2µF bypass capacitor.
•External dimensions (Units: mm)
BH9595FP-Y
BH9596FP-Y
13.6 ± 0.2
2.75 ± 0.1
14
0.11
1.9 ± 0.1
1
13
1.95 ± 0.1
0.8
0.36 ± 0.1
0.3Min.
0.15
HSOP25
6
0.25 ± 0.1
5.4 ± 0.2
7.8 ± 0.3
25
∗1
∗2
∗3
When mounted on a 90 × 50 × 1.6 (mm) glass epoxy board.
Reduced by 11.6mW for each increase in Ta of 1°C over 25°C.
Can withstand continuous use of 64% duty, at 25°C.