Datasheet HS-245RH, HS-246RH, HS-248RH Datasheet (Intersil Corporation)

HS-245RH, HS-246RH, HS-248RH

Data Sheet August 1999

HS-245RH Radiation Hardened Triple

Line Transmitter

HS-246RH Radiation Hardened Triple

Line Receiver

HS-248RH Radiation Hardened Triple

Party-Line Receiver

The HS-245RH/246RH/248RH radiation hardened triple line
transmitter and triple line receivers are fabricated using the
Intersil dielectric isolation process. These parts are identical in
pinout and function to the original HD-245/246/248. They are
also die size and bond pad placement compatible with the
original parts for those customers who buy dice for hybrid
assembly.

Each transmitter-receiver combination provides a digital
interface between systems linked by 100Ω twisted pair,
shielded cable. Each device contains three circuits
fabricated within a single monolithic chip. Data rates greater
than 15MHz are possible depending on transmission line
loss characteristics and length.

The transmitter employs constant current switching which
provides high noise immunity along with high speeds, low
power dissipation, low EMI generation and the ability to
drive high capacitance loads. In addition, the transmitters
can be turned “off” allowing several transmitters to time­share a single line.

Receiver input/output differences are shown in the table:

PART NO. INPUT OUTPUT

HS-246RH 100Ω Open Collector
HS-248RH Hi-Z 6K Pull-Up Resistors

The internal 100Ω cable termination consists of 50Ω from
each input to ground.

HS-248RH ‘‘party line’’ receivershave a Hi-Z input such that
as many as ten of these receivers can be used on a single
transmission line.

Each transmitter inputandreceiv eroutputcan be connected to
TTL and DTL systems. When used with shielded transmission
line, the transmitter-receiver system has v ery high immunity to
capacitance and magnetic noise coupling from adjacent
conductors. The system can tolerate ground differentials of

-2.0V to +20.0V (transmitter with respect to receiver).

Specifications for Rad Hard QML devices are controlled
by the Defense Supply Center in Columbus (DSCC). The
SMD numbers listed here must be used when ordering.

Detailed Electrical Specifications for these devices are
contained in SMD 5962-96722 and 5962-96723. A “hot­link” is provided on our homepage for downloading.
http://www.intersil.com/spacedefense/space.htm

File Number 3034.2

Features

• Electrically Screened to SMD # 5962-96722 and 5962­96723

• QML Qualified per MIL-PRF-38535 Requirements

• Radiation Hardened DI Processing

- Total Dose (γ) . . . . . . . . . . . . . . . . . . . 2 x 10

- Latchup Free

- Neutron Fluence . . . . . . . . . . . . . . . . . 5 x 10

• Replaces HD-245/246/248

• Current Mode Operation

• High Speed with 50 Foot Cable . . . . . . . . . . . . . . . 15MHz

High Speed with 1000 Foot Cable . . . . . . . . . . . . . . 2MHz

• High Noise Immunity

• Low EMI Generation

• Low Power Dissipation

• High Common Mode Rejection

• Transmitter and Receiver Party Line Capability

• Tolerates -2.0V to +20.0V Ground Differential (Transmitter
with Respect to Receiver)

• Transmitter Input/Receiver Output TTL/DTL Compatible

5

RADs(Si)

12

N/cm2

Ordering Information

INTERNAL

ORDERING NUMBER

5962R9672201QCC HS1-245RH-8 -55 to 125
5962R9672201QXC HS9-245RH-8 -55 to 125
5962R9672201VCC HS1-245RH-Q -55 to 125
5962R9672201VXC HS9-245RH-Q -55 to 125
HS9-245RH/PROTO HS9-245RH/PROTO -55 to 125
5962R9672301QCC HS1-246RH-8 -55 to 125
5962R9672301QXC HS9-246RH-8 -55 to 125
5962R9672301VCC HS1-246RH-Q -55 to 125
5962R9672301VXC HS9-246RH-Q -55 to 125
5962R9672302QCC HS1-248RH-8 -55 to 125
5962R9672302QXC HS9-248RH-8 -55 to 125
5962R9672302VCC HS1-248RH-Q -55 to 125
5962R9672302VXC HS9-248RH-Q -55 to 125

MKT. NUMBER

TEMP. RANGE

(oC)

1

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

www.intersil.com or 321-724-7143 | Copyright © Intersil Corporation 1999

Pinouts

HS-245RH, HS-246RH, HS-248RH

HS9-245RH 14 PIN FLATPACK

HS1-245RH 14 CERAMIC DIP

MIL-STD-1835 CDIP2-T14

TOP VIEW

HS9-246RH/248RH 14 PIN FLATPACK

HS1-246RH/248RH 14 PIN CERAMIC DIP

MIL-STD-1835 CDFP3-F14

TOP VIEW

GND

1

2

T1

3

4

5

T2

6

7

T3

14

13

12

11

10

9

8

φ1 INPUT
φ1 OUTPUT
φ2 OUTPUT

φ2 INPUT

φ1 INPUT
φ1 OUTPUT

SUBSTRATE

Test Circuits and Applications

NOTES:
Input: TTLH ≤ 10ns

TTHL ≤ 10ns
pw = 500ns
f = 1MHz

VOUT

IOUT =

50Ω

φ1 IN
φ2 IN

TPHL

φ1 OUT

φ2 OUT

VCC

INPUT

OUTPUT

OUTPUT

INPUT
INPUT

OUTPUT

φ2

φ1
φ2

φ2
φ1

φ2

TPLH

OPEN
(

≈3.2V)

0V
OPEN

(

≈3.2V)

0V

≈0.15V

≈3mA)

(
0V

≈0.15V

≈3mA)

(

0V

(-) INPUT

(+) INPUT

(R1) OUTPUT

(-) INPUT

(+) INPUT

(R2) OUTPUT

GND

φ1

φ2

1
2
3
4
5
6

7

D.U.T.

R1

R2

R3

VCC = +5V

VCC (R1 AND R2)

14

VCC (R3)

13

VEE (R1 AND R2)

12

VEE (R3)

11

OUTPUT (R3)

10

INPUT (+)

9
8

INPUT (-)

VOUT

50Ω
1%

TRANSMITTER

VOUT

50Ω
1%

φ1

OUT

φ2

NOTES:
Input: TTLH ≤ 10ns

TTHL ≤ 10ns
pw = 500ns
f = 1MHz

RECEIVER

All timing measurements referenced to 50% V points

(+)IN
(-) IN

OUT

All timing measurements referenced to 50% V points

FIGURE 1. CIRCUIT #1 TRANSMITTER PROPAGATION DELAY

150mV

0V
150mV

0V

TPLH

TPHL

5V

0V

(+)

(-)

FIGURE 2. CIRCUIT #2 RECEIVER PROPAGATION DELAY

2

50Ω
50

Ω

VCC = +5V

D.U.T.

VEE = - 5V

520Ω

800Ω

30pF

RECEIVER
OUTPUT

HS-245RH, HS-246RH, HS-248RH

Test Circuits and Applications (Continued)

+5V

IN

1/3
HS-245RH

ENABLE

NOTE: HS-245RH should be driven by open-collector
gates. (Totem-pole output may cause slight reduction in
“on” data current). For more detailed information, refer to
Design Information section of this data sheet.

(NOTE)

FIGURE 3. TYPICAL APPLICATION

Voltage Mode Transmission

Data rates of up to 10 million bits per second can be
obtained with standard TTL logic; however, the transmission
distance must be very short. For example, a typical 50 foot
low capacitance cable will have a capacitance of
approximately 750pF which requires a current of greater
than 50mA to drive 5V into this cable at 10MHz; therefore,
voltage mode transmitters are undesirable for long
transmission lines at high data rates due to the large current
required to charge the transmission line capacitance.

Current Mode Transmission

An alternate method of driving high data rates down long
transmission lines is to use a current mode transmitter.
Current mode logic changes the current in a low impedance
transmission line and requires very little change in voltage.
For example, a 2mA change in transmitter current will
produce a 100mV change in receiver voltage independent of
the series transmission line resistance. The rise time at the
receiver for a typical 50 foot cable (750pF) is approximately
30ns for a 2mA pulse.

+5V

1/3 HS-246RH

50Ω

50

Ω

-5V

“PARTY-LINE”

RECEIVER

-5V

RECEIVER
OUT

OUTPUT

(-)

(+)

(+)

(-)

+5V

1/3
HS-248RH

An emitter coupled logic gate is frequently used for a current
mode transmitter. However, ECL gates are not compatible
with TTL and DTL logic and they require considerable power.
The Intersil HS-245RH is a TTL/DTL compatible current
mode transmitter designed for high data rates on long
transmission lines. Data rates of 15 megabits per second
can be obtained with 50 feet of transmission line when using
the companion HS-246RH receiver. Data rates of 2 megabits
per second are easily obtained on transmission lines as long
as 1,000 feet. The Intersil transmitter and receivers feature
very low power, typically 25mW for the transmitter and
15mW for the receiver.

Intersil Transmitter/Receivers

The Intersil transmitter/receiver family consists of a triple line
transmitter,two triple line receivers with internal terminations
and a triple party-line receiver.The general characteristics of
the transmitter and receivers are outlined in Table A.

3

HS-245RH, HS-246RH, HS-248RH

TABLE A. GENERAL TRANSMITTER/RECEIVER CHARACTERISTICS

TRIPLE LINE TRANSMITTER

PARAMETER HS-245RH UNITS COMMENTS

Operating Temperature Range -55 to 125
“ON” Output Current 1.0 Min mA Over Full Temperature Range
Power Supply Current 7.0 Max mA Per Transmitter Section
Standby Current 33 Max µA Per Transmitter Section
Propagation Delay 14 Max ns Over Full Temperature Range

TRIPLE LINE RECEIVER

PARAMETER RECEIVER TYPE LIMITS UNITS COMMENTS

Operating Temperature Range HS-246RH/248RH -55 to 125

o

C

o

C

Power Supply
ICC (VCC = +5.0V)

Propagation Delay All Receivers 30 ns Over Full Temperature Range

Input Impedance and
Output Circuit

Transmitter

The HS-245RH transmitters have two inputs per transmitter,

HS-246RH/248RH 2.6 mA Per Receiver Section

INPUT

HS-246RH
HS-248RH Hi-Z 6K Pull-Up Resistor

100 Open Collector

IN

G1

Ω

G2

OUTPUT

either of which is low while the other is open during normal
operation and both inputs are open during standby. For

G3

optimum transmitter performance, the “off” input should be
open circuit rather than being pulled towards +5V, because

ENABLE

this will reduce the “on” output data current. On the other
hand, the “on” and “off” output data current will increase if
the “off” input is held below its open circuit voltage. Open
collector gates such as the 7401 and 7403 or 7405 Hex­Inverter are suitable for driving the HS-245RH transmitter
inputs. By using 2-input gates as shown in Figure 6, an

1/3
HS-245RH

1/3
HS-246RH

enable line can be provided so that more than one
transmitter may be connected to a line for time sharing.
When the enable line is low the transmitter will be disabled
and will present a high impedance to the transmission line
as well as requiring very little power supply current.

Complementary input signals may be derived from high
speed inverter gates as shown, or by using the

+5 GND

2K-6K FOR TTL DRIVE

REQUIRED FOR HS-246RH

1/3
HS-248RH

-5V

+5VGND

complementary outputs of a flip-flop. When the transmitter is
connected near the midpoint of a long transmission line or to
a line with terminations at both ends, two transmitter
sections should be paralleled with respective inputs and

-5V+5VGND

outputs connected together in order to drive the reduced
impedance. This parallel transmitter technique can also be

FIGURE 4. TYPICAL DATA TRANSMISSION SYSTEM

used to increase the data rate on long transmission lines.

OUT

OUT

4

HS-245RH, HS-246RH, HS-248RH

Transmitter Operation

The transmitter alternately applies the current to each of the
two conductors in the twisted pair line such that the total
current in the twisted pair is constant and alwaysin the same
direction. This current flows through either of the two 50V
terminating resistors at the receiver and returns to the
transmitter as a steady DC current on the transmission line
shield. The DC power supply return for the transmitter is
through the receiver terminating resistors (the transmitter
ground pin is only a substrate ground). Therefore, it is
essential that the shield be connected to the power supply
common at both the transmitter and receiver, preferably at
the integrated circuit “ground” pin. More than fifteen twisted
pair lines can share the same shield without crosstalk.

Receivers

The HS-248RH “party-line” receiver presents a high
impedance load to the transmission line allowing as many as
ten HS-248RH receivers to be distributed along a line without
excessive loading. Figure 6 shows a typical system of a
transmitter, a terminating receiver and a party-line receiver.
The transmission line is terminated in its characteristics
impedance by an HS-246RH or by a pair of 50Ω resistors
connecting each line to the ground return shield.

Transmission Lines

The maximum frequency (or minimum pulse width) which
can be carried by a certain length of a given transmission
line is dependent on the loss characteristics of the particular
line. At low frequencies, there will be virtually no loss in
pulse amplitude, but there will be a degradation of rise and
fall-time which is roughly proportional to the square of the
line length. This is shown in Figure 7. If the pulse width is
less than the rise-time at the receiver end, the pulse
amplitude will be diminished, approaching the point where it
cannot be detected by the receiver.

150mV

LINE

VOLTAGE

AT TRANS-

MITTER

TTLH1 TTHL1

150mV

LINE

VOLTAGE

AT

RECEIVER

TTLH2

WIDE PULSE

TRLH2 = TTLH1 KL
TTHL2 = TTHL1 KL

FIGURE 5. TRANSMISSION LINE WAVE-SHAPING

TTHL2

2

2

0V

TTLH2 TTHL1

0V

TTLH2 TTHL2

MINIMUM PULSE WIDTH

Where: L is Line Length K is

determined by line loss
characteristics

The transmission line used with the Intersil HS-245RH
series transmitter and receivers can be any ordinary
shielded, twisted pair line with a characteristic impedance of
100Ω. Twisted pair lines consisting of number 20 or 22
gauge wire will generally havethis characteristic impedance.
Special high quality transmission lines are not necessary
and standard audio, shielded-twisted pair, cable is generally
suitable.

Since the necessary characteristics for various twisted pair
lines are not readily available, it may be necessary to take
some measurements on a length of the proposed line. Todo
this, connect an HS-245RH transmitter to one end of the line
(100 feet or more) and an HS-246RH to the other end. The
rise and fall-times can be measured on the line at both ends
and the constant ‘‘K’’, for that line can be computed as
shown in Figure 7 so that the minimum pulse width can be
determined for any length of line.

Data rates of 2MHz have been obtained using 1,000 feet of
standard shielded, twisted pair, audio cable. Data rates of
15MHz are possible on shorter lengths of transmission line
(50 feet).

Electromagnetic Interference

Very little electromagnetic interference is generated by the
Intersil current mode system because the total current
through the twisted pair is constant, while the current
through the shield is also constant and in the opposite
direction. This can be verified by observing, with a current
probe, the total current through the twisted pair, through the
shield and through the complete shielded, twisted pair cable.
In each case a constant current will be observed with only
small variations. Small pulses may be observed if the
complementary inputs to the transmitter do not switch at the
same time. The current will decrease during the time both
inputs are high, and will increase during the time both inputs
are low. These switching pulses may be observed when
using the circuit shown in Figure 6. The amplitude and shape
of these pulses will depend of the propagation delay of G1,
and transition times G2 and G3. These pulses are generally
of no concern because of their small amplitude and width,
but they may be reduced by increasing the similarity of the
waveforms and timing synchronization of the complementary
signals applied to the transmitter.

In addition to generating very little noise, the system is also
highly immune to outside noise since it is difficult to
capacitively couple a differential signal into the low
impedance twisted pair cable and it is even more difficult in
induce a differential current into the line due to the very high
impedance of the constant current transmitter. Therefore,
differential mode interference is generally not a problem with
the Intersil current mode system. Large common mode
voltages can also be tolerated because the output current of
the transmitter is constant as long as the receiver
termination ground is less than 2V positive with respect to

5

HS-245RH, HS-246RH, HS-248RH

the grounded input of the transmitter, and is less than 25V
negative with respect to the transmitter VCC. The current
mode system is totally unaffected by ground differential
noise of +2V at frequencies as high as 1MHz.

Propagation Delay

The worst case propagation delay of a transmitter and
receiver, connected as shown in Figure 6, can be
determined by adding the maximum delay shown on the
data sheet for the transmitter and receiver. These overall
switching characteristics are shown in TableB. For the entire
system, however, the propagation delay of the transmission
line must also be considered. This delay, of course, depends
on the length of the line and the characteristics of the line,

Schematics

2.7K 2.7K

380Ω

but in general, delays of between 1.5ns and 3.0ns per foot
can be expected.

TABLE B. OVERALL TRANSMITTER/RECEIVER SWITCHING

CHARACTERISTICS

-55oC TO 125oC

HS-245RH, HS-246RH

HS-248RH

CHARACTERISTICS

Propagation Delay
TPLH

Propagation Delay
TPHL

Duty Cycle Distortion
TPLH - TPHL

NOTE: VCC = +5V, VEE = -5V.

14VCC

-1840ns

-1840ns

- 2 15 ns

UNITSMIN TYP MAX

(R1) +INPUT

GND

300Ω

2.0K 2.0K
12 34

φ1

φ1

IN

OUTφ2INφ2OUT

T1

56 89

φ1INφ1

OUTφ2INφ2OUT

T2

10 11 12 13

φ1INφ1

OUTφ2INφ2OUT

T3

FIGURE 6. HS-245RH

14VCC

(R1) OUTPUT

1

(R1)
50Ω

3

+INPUT

-INPUT

5

(R2)

12VEE 11VEE

6K

4.1K

-INPUT

2

50Ω

7

2.7K

6

+INPUT

4

(R2)

13VCC

10

(R3) OUTPUT(R2) OUTPUT

-INPUT

9

(R3)

8

(R3)

R1

FIGURE 7. HS-246RH, HS-248RH

NOTES:

1. HS-246RH does not have 6K output pull-up resistors.

2. HS-248RH does not have 50Ω input termination resistors.

6

R2 R3

Die Characteristics

HS-245RH

DIE DIMENSIONS:

45 mils x 45 mils x 11 mils
1140µm x 1140µm x 280µm

INTERFACE MATERIALS:
Glassivation:

Type: Silox
Thickness: 8k

Å ±1kÅ

Top Metallization:

Type: Aluminum
Thickness: 12.5k

Å ±2kÅ

Substrate:

HFSB Bipolar/Dielectric Isolation

Backside Finish:

Silicon

Metallization Mask Layout

HS-245RH

OUTPUT f1

INPUT f1

ASSEMBLY RELATED INFORMATION:
Substrate Potential:

Unbiased

ADDITIONAL INFORMATION:
Worst Case Current Density:

4

2

7.8 x 10

A/cm

Transistor Count:

6

VCC

INPUT f2

OUTPUT f2

INPUT f2

INPUT f1

OUTPUT f1

SUBSTRATE

GND

INPUT f2

OUTPUT f2

OUTPUT f2

OUTPUT f1

INPUT f1

7

Die Characteristics

HS-246RH, HS-248RH

DIE DIMENSIONS:

45 mils x 47 mils x 11 mils
1140µm x 1190µm x 280µm

INTERFACE MATERIALS:
Glassivation:

Type: Silox
Thickness: 8k

Å ±1kÅ

Top Metallization:

Type: T.W.
Thickness: 2.5k

Å ±0.5kÅ

Type: Al
Thickness: 14k

Å ±2kÅ

Substrate:

ALPS Bipolar/Dielectric Isolation

Backside Finish:

Silicon

Metallization Mask Layout

HS-246RH HS-248RH

ASSEMBLY RELATED INFORMATION:
Substrate Potential:

Unbiased

ADDITIONAL INFORMATION:
Worst Case Current Density:

5

2

1.4 x 10

A/cm

Transistor Count:

9

(+) INPUT

(-) INPUT

VCC R1 AND R2

OUTPUT R1

(-) INPUT

(+) INPUT

3

GND

OUTPUT R2

(-) INPUT

VCC R3

VEE R1 AND R2

VEE R3

OUTPUT R3

(+) INPUT

OUTPUT R1

(-) INPUT

(+) INPUT

(+) INPUT

(-) INPUT

GND

OUTPUT R2

VCC R1 AND R2

VCC R3

(-) INPUT

(+) INPUT

VEE R1 AND R2

VEE R3

OUTPUT R3

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Intersil semiconductor products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design and/or specifications at any time with­out notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However ,no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.

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8