ML4621CP datasheet(7/8 Pages) MICRO-LINEAR

No. de pieza	ML4621CP

Descripción Electrónicos	Data Quantizer

Download	8 Pages

Scroll/Zoom	100%

Fabricante Electrónico	MICRO-LINEAR [Micro Linear Corporation]

Página de inicio	http://www.microlinear.com

Logo

7 / 8 page

ML4621

7

Figure 3.

Figure 2.

VOUT+

VOUT–

VOS

The equation which determines the droop rate of the peak

detector is:

dV

dt

I

C

ISET

=

(3)

In this equation C is the peak capacitor at CPEAK. On the

ML4621 the droop rate of the peak detector can be

adjusted two ways:

1) By adjusting the value of the peak capacitor at CPEAK.

2) By adjusting the charge current into the peak capacitor

at ISET.

The charge current, IISET, can be controlled externally by

connecting a resistor, REXT, between ISET and VCC. IISET

will then be:

I

V

R

ISET

CC

EXT

=

+

–.

07

1700

(4)

For convenience an on-chip current source of 125µA is

available by connecting INOM to ISET.

The threshold generator level-shifts the reference voltage

at VTHADJ through a circuit which has a temperature

coefficient matching that of the limiting amplifier. The

relationship between VTHADJ and VTH (the minimum

peak voltage at the input which will trigger the link

monitor) is:

VADJ

V

TH

=¥

+

600

0 7

bg

.

(5)

The on-chip reference voltage, VREF, can be tied directly

to VTHADJ to set the threshold level. This will set the

minimum input signal on the ML4621 at about 3mV

(peak). A lower threshold level can be set by dividing

down VREF with a resistor string, as in Figure 3.

Since the ML4621 has a relatively low input impedance

of 6.8k

Ω and is offset by one diode drop, the equation

which accounts for the load and offset is:

VADJ

RV

R

RR

R

TH

REF

=

¥¥

+

¥

¥+

+

¥

21

12

1

2

6800

0 7

6800

bg b

g

ch

bg

.

(6)

THRESHOLD ADJUSTMENT EXAMPLE

To make the link monitor trigger when the received

optical power goes below 1µW (-30dBm), you first need to

calculate the resultant voltage at VIN+ and VIN–. If a

Hewlett-Packard HFBR-24X6 fiber-optic receiver with a

responsive level of 8mV/µW is used, the peak-to-peak

voltage would be:

1

8

µ

W

mV

W

mVPP

¥=

-

(7)

Then the link monitor should trigger at some point slightly

lower than 4mV peak. Setting VTH in Equation 5 to 3mV

and solving for VTHADJ yields:

VTHADJ = (600 × 0.003) + 0.7 = 2.5V

(8)

This is a convenient value since the reference voltage

supplied by the quantizer, VREF, is 2.5V.

The link monitor has about 0.4mV (peak) hysteresis

built-in. More hysteresis can be induced by connecting a

resistor between TTL LINK MON and VTHADJ creating a

positive feedback loop.

Refer to Micro Linear’s Application Note 6 for more

detail.

FUNCTIONAL DESCRIPTION (Continued)

VREF

VTHADJ

REF

THRESHOLD

GENERATOR

R1

R2

Número de pieza similar - ML4621CP

Fabricante Electrónico	No. de pieza	Datasheet	Descripción Electrónicos
Micro Linear Corporatio...	ML4622	170Kb / 8P	Fiber Optic Data Quantizer
	ML4622CP	170Kb / 8P	Fiber Optic Data Quantizer
	ML4622CS	170Kb / 8P	Fiber Optic Data Quantizer
	ML4622IS	170Kb / 8P	Fiber Optic Data Quantizer
	ML4624CP	170Kb / 8P	Fiber Optic Data Quantizer

More results

Descripción similar - ML4621CP

Fabricante Electrónico	No. de pieza	Datasheet	Descripción Electrónicos
Micro Linear Corporatio...	ML6622	94Kb / 6P	High-Speed Data Quantizer
Micro Linear Corporatio...	ML4622	170Kb / 8P	Fiber Optic Data Quantizer
Analog Devices	AD807	472Kb / 12P	Fiber Optic Receiver with Quantizer and Clock Recovery and Data Retiming REV. B
	AD807	226Kb / 12P	Fiber Optic Receiver with Quantizer and Clock Recovery and Data Retiming REV. A
	AD808	153Kb / 12P	Fiber Optic Receiver with Quantizer and Clock Recovery and Data Retiming REV. 0
	AD808	145Kb / 12P	Fiber Optic Receiver with Quantizer and Clock Recovery and Data Retiming REV. 0
	AD807	472Kb / 12P	Fiber Optic Receiver with Quantizer and Clock Recovery and Data Retiming REV. B
Advanced Micro Devices	AM79865	805Kb / 17P	PHYSICAL DATA TRANSMITTER/PHYSICAL DATA RECEIVER
List of Unclassifed Man...	LPE16000	601Kb / 2P	Assures data availability and data integrity
ATMEL Corporation	45DB081B	12Kb / 6P	AT-45DB081B DATA FLASH RELIABILITY DATA

More results

ML4621CP Datasheet(PDF) 7 Page - Micro Linear Corporation

ML4621CP Datasheet(HTML) 7 Page - Micro Linear Corporation

Número de pieza similar - ML4621CP

Descripción similar - ML4621CP

Html Pages

1 2 3 4 5 6 7 8

Datasheet Descarga

Enlace URL