3

UCC5641

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNITS

Regulator Section

1.25V Regulator

DIFSENS connected to DIFFB

1.15

1.25

1.35

V

1.25V Regulator Source Current

DIFSENS connected to DIFFB

–100

–80

mA

1.25V Regulator Sink Current

DIFSENS connected to DIFFB

80

100

mA

1.3V Regulator

DIFFB connected to GND

1.2

1.3

1.4

V

1.3V Regulator Source Current

DIFSENS to GND

–15

–5

mA

1.3V Sink Current

DIFSENS to 3.3V

50

200

µA

Differential Termination Section

Differential Impedance

–2.5mA to 4.5mA

100

105

110

Ω

Common Mode Impedance

L+ connected to L–

110

150

165

Ω

Differential Bias Voltage

No load, L+ or L–

100

125

mV

Common Mode Bias

1.15

1.25

1.35

V

Output Leakage, Disconnect

DISCNCT, TRMPWR = 0 to 5.25V,

10

400

nA

Output Capacitance

Single ended measurement to ground (Note 1)

3

pF

Low Voltage Differential (LVD) Status Bit Section

–6

–4

mA

2

5

mA

Disconnect & Differential Sense Input Section

DISCNCT Threshold

0.8

2

V

Input Current

At 0V and 3.3V

–30

–10

µA

Differential Sense SE to LVD Threshold

0.5

0.7

V

Differential Sense LVD to HPD Threshold

1.9

2.4

V

Note 1: Guaranteed by design. Not 100% tested in production.

PIN DESCRIPTION

DIFFB: Differential sense filter pin should be connected

to a 0.1

µF capacitor and 20k resistor to Diff Sense.

DIFSENS: The SCSI bus differential sense line to detect

what type of devices are connected to the SCSI Bus.

DISCNCT: Disconnect pin shuts down the terminator

when it is not at the end of the bus.

GND: Ground.

L

SCSI Bus.

L

SCSI Bus.

LVD: (28 pin package only) Indicates that the bus is in

LVD mode.

REG: Regulator bypass; must be connected to a 4.7 F

capacitor to ground.