Texas Instruments UCC5638FQPTR, UCC5638FQP Datasheet

Multimode SCSI 15 Line Terminator

UCC5638

FEATURES

Auto Selection Single Ended (SE) or

•

Low Voltage Differential (LVD)
Termination

Meets SCSI-1, SCSI-2, SCSI-3, SPI,

•

Ultra (Fast-20), Ultra2 (SPI-2 LVD
SCSI) and Ultra3/Ultra160 Standards

2.7V to 5.25V Operation

•

Differential Failsafe Bias

•

Thermal packaging for low junction

•

temperature and better MTBF.

BLOCK DIAGRAM

2.15V

34DIFFB

0.6V

DESCRIPTION

The UCC5638 Multimode SCSI Terminator provides a smooth transition
into the next generation of the SCSI Parallel Interface (SPI-2). It automati
cally senses the bus, via DIFFB, and switches the termination to either sin
gle ended (SE) or low voltage differential (LVD) SCSI, dependent on which
type of devices are connected to the bus. The UCC5638 can not be used
on a HVD, EIA485, differential SCSI bus. If the UCC5638 detects a HVD
SCSI device, it switches to a high impedance state.

The Multimode terminator contains all functions required to terminate and
auto detect and switch modes for SPI-2 bus architectures. Single Ended
and Differential impedances and currents are trimmed for maximum effec
tiveness. Fail Safe biasing is provided to insure signal integrity. Device/Bus
type detection circuitry is integrated into the terminator to provide automatic
switching of termination between single ended and LVD SCSI and a high
impedance for HVD SCSI. The multimode function provides all the perform
ance analog functions necessary to implement SPI-2 termination in a sin
gle monolithic device.

The UCC5638 is offered in a 48 pin LQFP package for a temperature range
of 0°C to 70°C.

HIGH POWER
DIFFERENTIAL

LOW VOLTAGE
DIFFERENTIAL

SINGLE ENDED

(NOISE LOAD)

REF

1.3V

–15mA ≤ I
50µA ≤ I

SOURCE

SINK

≤ –5mA

≤ 200µA

1.3V
35 DIFFSEN

-

-

-

-

-

REF

2.7V

REF

1.25V

10µA

DISCNCT

36

3TRMPWR

HS/GND

27

GND

4-9

SLUS271A - FEBRUARY 2000

SOURCE/SINK REGULATOR

SE

HS/GND

28-33

ALL SWITCHES

UP

DOWN

OPEN

MODE

LVD

DISCNCT

10

REG

4.7µF .

110

124

110

124

56mV

–+

56mV

+–

SE GND SWITCH

56mV

–+

56mV

+–

SE GND SWITCH

52.5

52.5

52.5

52.5

12

11

2

1

L1–

L1+

L15–

L15+

UDG-98063

UCC5638

ABSOLUTE MAXIMUM RATINGS

TRMPWR Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +6V

Signal Line Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . 0V to 5V

Package Dissipation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2W

Storage Temperature . . . . . . . . . . . . . . . . . . . –65°C to +150°C

Junction Temperature. . . . . . . . . . . . . . . . . . . –55°C to +150°C

Lead Temperature (Soldering, 10 sec.). . . . . . . . . . . . . +300°C

Recommended Operating Conditions . . . . . . . . . 2.7V to 5.25V

Currents are positive into negative out of the specified terminal.
Note: Consult Packaging Section of Databook for thermal limi

-

tations and considerations of package.

RECOMMENDED OPERATING CONDITIONS

TRMPWR Voltage . . . . . . . . . . . . . . . . . . . . . . . . 2.7V to 5.25V

Temperature Ranges . . . . . . . . . . . . . . . . . . . . . . 0°C to +70°C

CONNECTION DIAGRAMS

(TOP VIEW)
FQP Package

HS/GND
HS/GND
HS/GND

REG

L1+
L1–

12

10

8

7

9

27

28

313233

29

30

L8+
L8–

GND
HS/GND
HS/GND
HS/GND

L2+
L2–
L3+
L3–
L4+
L4–
L5+
L5–
L6+
L6–
L7+
L7–

11

13
14
15
16

17
18
19
20

21
22
23
24

25

26

HS/GND
HS/GND
HS/GND

TRMPWR
L15–
L15+

6

4

321

5

35

34

L14–

48
47

L14+
L13–

46

L13+

45

L12–

44

L12+

43

L11–

42

L11+

41

L10–

40

L10+

39
38

L9–

37

L9+

36

DISCNCT
DIFFSENS
DIFFB
HS/GND
HS/GND
HS/GND

ELECTRICAL CHARACTERISTICS

Unless otherwise stated, these specifications apply for TA=TJ= 0°C to 70°C,

TRMPWR = 3.3V.

PARAMETER TEST CONDITIONS MIN TYP MAX UNITS

TRMPWR Supply Current Section

TRMPWR Supply Current LVD SCSI Mode 20 25 mA

SE SCSI Mode 1.6 10 mA
Disabled Terminator 250 400

Regulator Section

1.25V Regulator LVD SCSI Mode 1.15 1.25 1.35 V

1.25V Regulator Source Current V

1.25V Regulator Sink Current V

= 0V –375 –700 –1000 mA

REG

= 3.3V 170 300 700 mA

REG

1.3V Regulator Diff Sense 1.2 1.3 1.4 V

1.3V Regulator Source Current V

1.3V Regulator Sink Current V

= 0V –15 –5 mA

REG

= 3.3V 50 200 A

REG

2.7V Regulator SE SCSI Mode 2.5 2.7 3.0 V

2.7V Regulator Source Current V

2.7V Regulator Sink Curren V

= 0V –375 –700 –1000 mA

REG

= 3.3V 170 300 700 mA

REG

Differential Termination Section

Differential Impedance 100 105 110
Common Mode Impedence (Note 2) 110 150 165
Differential Bias Voltage 100 125 mV
Common Mode Bias 1.15 1.25 1.35 V
Output Capacitance Single Ended Measurement to Ground (Note 1) 3 pF

A

2