TNETEL1400

EtherLoop

™ TRANSCEIVER

SPHS004A – FEBRUARY 1999 – REVISED MARCH 1999

9

POST OFFICE BOX 655303

transmitter (see Figure 5) (continued)

PARAMETER

TEST CONDITIONS

MIN

TYP†

MAX

UNIT

Irms(TXOP)–

Irms(TXON)

TX output

current balance

VCC = 5 V, RL = 110 Ω,

RX_TERM = 0, TX_EN = 1,

V(TXINP) = 1.2 VPP sinusoid at f = 500 kHz

(see Note 1)

TXGAIN = 0000,

RXGAIN = 0XX

–5

5

mA

TX output stability

Source impedance

≤ 50 Ω,

Supply impedance

≤ 10 Ω,

Zloads: voltage standing-wave ratio (VSWR) 4:1

and open circuit

TXGAIN = 0000,

RXGAIN = 0XX

TX supply current

VOUT = 0,

TXGAIN = 0000

35

45

mA

TX supply current

VOUT = MAX,

TXGAIN = 0000

120

mA

TX output return loss

TXGAIN = 0000, RXGAIN = 0XX

18

dB

TX power-up time

TXGAIN = 0000, RXGAIN = 0XX (see Note 2)

100

µs

† All typical values are at VCC = 5 V, TA = 25°C (unless otherwise noted).

NOTES:

1. While the RX circuit is disabled during transmission, it is still connected and, therefore, must withstand the signal levels placed at

its input terminals.

2. The power-up/power-down time is the time it takes for the signal path to completely settle and meet all the transmission specifications

after TXGAIN and RXGAIN are set to power-up condition or switched from one gain setting to another. This time consists of slewing

and exponential settling of bias and AC coupling capacitors and, therefore, the values of these components must be as shown in

the application diagram, Figure 4.

receiver (see Figures 6 and 7)

PARAMETER

TEST CONDITIONS

MIN

TYP†

MAX

UNIT

RL =2kΩ CL =20 pF 30kHz<f<275 MHz

RXGAIN = 11

691

RX idle channel noise

RL = 2 kΩ, CL = 20 F, 30 kHz < f < 2.75 MHz,

RX_TERM = 1, TX_EN = 0,

RXGAIN = 10

478

µV

RX idle channel noise

_

,

_

,

V(RXIP – RXIN) = 0.04 VPP sinusoid at f = 500 kHz

(N t 3)

RXGAIN = 01

266

µ

RMS

(see Note 3)

RXGAIN = 00

160

RXGAIN = 11

24

30

31

RX gain accuracy

VCC = 5 V, RL = 2 kΩ, CL = 20 pF,

30 kHz<f<2 75 MHz RX TERM

1 TX EN

0

RXGAIN = 10

23

24

25

dB

RX gain accuracy

30 kHz < f < 2.75 MHz, RX_TERM = 1, TX_EN = 0,

V(RXIP – RXIN) = 0.04 VPP sinusoid at f = 500 kHz

RXGAIN = 01

11

12

13

dB

V(RXIP – RXIN) = 0.04 VPP sinusoid at f = 500 kHz

RXGAIN = 00

–1

0

1

RX gain over frequency

(WRT gain at 500 kHz)

RL = 2 kΩ, CL = 20 pF, 30 kHz < f < 2.75 MHz,

30 kHz < f < 2.5 MHz monotically decreasing

for f > 3 MHz, TX_EN = 0,

V(RXIP – RXIN) = 0.04 VPP sinusoid at f = 500 kHz

RX_TERM = 1,

RXGAIN = 111

–1

1

dB

RX power-supply

rejection

(WRT VCC only)

RL = 2 kΩ, CL = 20 pF, dc < f < 3 MHz, TX_EN = 0,

V(RXIP – RXIN) = 0.04 VPP sinusoid at f = 500 kHz

RX_TERM = 1,

RXGAIN = 111

0.03

V/V

RX common-mode

rejection

RL = 2 kΩ, CL = 20 pF, TX_EN = 0, V(RXIN) = 1.5 VPP,

V(RXIP – RXIN) = 0.04 VPP sinusoid at f = 500 kHz

RX_TERM = 1,

RXGAIN = 111

30

dB

RX IIP3 intercept

RL = 2 kΩ, CL = 20 pF, TX_EN = 0,

V(RXIP – RXIN) = 0.04 VPP sinusoid at f = 500 kHz

(see Note 4)

RX_TERM = 1,

RXGAIN = 111

17

dBm

† All typical values are at VCC = 5 V, TA = 25°C (unless otherwise noted).

NOTES:

3. Idle channel noise is the noise (Vrms) measured at RXOUT with no signal at RXIN. This voltage is integrated over the 30-KHz to

2.75-MHz band. This specification is in place of the original noise-figure specification, and is correlated to NF with laboratory

measurements.

4. The two tones used for this test are at 1.39 MHz and 1.58 MHz, and the in-band IIP3 products are at 1.2 MHz and 1.77 MHz. The

IIP3 intercept point is the output power level, where the power of the harmonics equals that of the signal frequencies. This point is

an intersection of two straight lines extrapolated from two low-power measurements.