Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsLinear ICsLinear IC - Custom amplification Limiting amplifier TQFN 20

General Description

The MAX3969 is a recommended upgrade for the

MAX3964 and MAX3968. The MAX3964A limiting amplifi-

er, with 2mV

P-P

input sensitivity and PECL data outputs, is

ideal for low-cost ATM, FDDI, and Fast Ethernet fiber

optic applications.

The MAX3964A features an integrated power detector

that senses the input-signal power. It provides a

received-signal-strength indicator (RSSI), which is an

analog indication of the power level and complementary

PECL loss-of-signal (LOS) outputs, which indicate when

the power level drops below a programmable threshold.

The threshold can be adjusted to detect signal ampli-

tudes as low as 2.7mV

P-P

. An optional squelch function

disables switching of the data outputs by holding them at

a known state during an LOS condition.

The MAX3968 provides the same functionality as the

MAX3964A, but has data-output edge speed suitable for

ESCON and 266Mbps fibre channel applications.

The MAX3964A/MAX3968 are available in die form, as

tested wafers, and in 20-pin QSOP packages. The

MAX3964AETP is available in a 20-pin thin QFN package.

Applications

125Mbps FDDI Receivers

155Mbps LAN ATM Receivers

Fast Ethernet Receivers

ESCON Receivers

155Mbps FTTx Receivers

Features

♦ Single Supply: +3.0V to +5.5V

♦ 2mV

P-P

Input Sensitivity

♦ 1.2ns Output Edge Speed

♦ Loss-of-Signal Detector with Programmable

Threshold

♦ Analog Received-Signal-Strength Indicator

♦ Output Squelch Function

♦ Compatible with 4B/5B Data Coding

MAX3964A/MAX3968

+3.0V to +5.5V, 125Mbps to 266Mbps

Limiting Amplifiers with Loss-of-Signal Detector

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

MAX3964A

MAX3968

CZN

CZP

RSSI

LOS+

1µF

FILTER

CC0

OUT-

GND

FILTER

10nF

4700pF

0.1µF

OUT+

155Mbps

TIA

IN-

IN+

LOS-

OUT-

OUT+

SUB*

GND

50Ω

≥100kΩ

INV

*PIN NOT AVAILABLE ON MAX3964AETP.

- 2V

SQUELCH

PHOTODIODE

Typical Operating Circuit

19-1314; Rev 5; 8/06

Pin Configurations and Selector Guide appear at end of data

sheet.

*Dice are designed to operate over a 0°C to +100°C junction

temperature (Tj) range, but are tested and guaranteed only at T

= +25°C.

**Package Code: T2044-1

+Denotes lead-free package.

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

PART TEMP RANGE PIN-PACKAGE

MAX3964AETP -40°C to +85°C 20 Thin QFN**

MAX3964AETP+

-40°C to +85°C 20 Thin QFN**

MAX3964AC/D -40°C to +85°C

Dice*

MAX3968CEP 0°C to +70°C 20 QSOP

MAX3968C/D 0°C to +70°C Dice*

EVALUATION KIT

AVAILABLE

Summary of content (11 pages)

PAGE 1
9-1314; Rev 5; 8/06 KIT ATION EVALU E L B A AVAIL +3.0V to +5.5V, 125Mbps to 266Mbps Limiting Amplifiers with Loss-of-Signal Detector Features The MAX3969 is a recommended upgrade for the MAX3964 and MAX3968. The MAX3964A limiting amplifier, with 2mVP-P input sensitivity and PECL data outputs, is ideal for low-cost ATM, FDDI, and Fast Ethernet fiber optic applications. The MAX3964A features an integrated power detector that senses the input-signal power.
PAGE 2
MAX3964A/MAX3968 +3.0V to +5.5V, 125Mbps to 266Mbps Limiting Amplifiers with Loss-of-Signal Detector ABSOLUTE MAXIMUM RATINGS (SUB, GND tied to ground) VCC, VCCO.............................................................-0.5V to +7.0V FILTER, RSSI, IN+, IN-, CZP, CZN, SQUELCH, LOS+, LOS-, INV, VTH, OUT+, OUT- ......-0.5V to (VCC + 0.5V) PECL Output Current (OUT+, OUT-, LOS+, LOS-) ............50mA Differential Voltage Between CZP and CZN..........-1.5V to +1.5V Differential Voltage Between IN+ and IN- ..
PAGE 3
+3.0V to +5.5V, 125Mbps to 266Mbps Limiting Amplifiers with Loss-of-Signal Detector MAX3964A/MAX3968 ELECTRICAL CHARACTERISTICS—MAX3964AETP (VCC = +3.0V to +5.5V, PECL outputs terminated with 50Ω to (VCC - 2V), TA = -40°C to +85°C. Typical values measured at VCC = +3.3V and TA = +25°C, unless otherwise noted.) PARAMETER SYMBOL Supply Current ICC CONDITIONS MIN PECL outputs open LOS Hysteresis Input = 4.0mVP-P (Note 2) TYP MAX UNITS 22 45 mA 5 8.0 dB 3.
PAGE 4
Typical Operating Characteristics (continued) (MAX3964A EV kit, VCC = +3.3V, decibels (dB) calculated as 20 log ∆V, PECL outputs terminated with 50Ω to (VCC - 2V), TA = +25°C, unless otherwise noted.) OUTPUT AMPLITUDE vs. INPUT VOLTAGE (DIFFERENTIAL SIGNAL LEVELS) DATA OUTPUT EDGE SPEED (20% to 80%) vs. TEMPERATURE OUTPUT AMPLITUDE (mV) 2.4 MAX3964A 1.8 1.2 MAX3968 MAX3964/65toc05 1600 MAX3964/65toc04 3.0 EDGE SPEED (ns) 1400 1200 1000 800 0.6 0 600 -50 -25 0 25 50 75 100 0.
PAGE 5
+3.0V to +5.5V, 125Mbps to 266Mbps Limiting Amplifiers with Loss-of-Signal Detector PIN THIN QFN NAME QSOP 1 19 SQUELCH 2 20 VTH Output of Internal Op Amp that Sets Loss-of-Signal Threshold Voltage (Figure 1). Connect a resistor from VTH to INV and from INV to ground (minimum resistance 100kΩ) to program the desired threshold voltage. 3 1 INV Inverting Input of Internal Op Amp that Sets Loss-of-Signal Threshold Voltage (Figure 1).
PAGE 6
MAX3964A/MAX3968 +3.0V to +5.5V, 125Mbps to 266Mbps Limiting Amplifiers with Loss-of-Signal Detector CAZ VCC CZP VCCO CZN OFFSET CORRECTION LIMITER LIMITER LIMITER I LIMITER I OUT+/OUT- O IN+/IN- SQUELCH LOS+ FWD FWD FWD FWD RSSI FILTER LOS+/LOSCFILTER VCC MAX3964A MAX3968 1.2V REFERENCE LOS COMPARATOR VTR INV SUB R1 GND R2 FWD = FULL-WAVE DETECTOR Figure 1.
PAGE 7
+3.0V to +5.5V, 125Mbps to 266Mbps Limiting Amplifiers with Loss-of-Signal Detector 120 200kV/W 100 VALUE OF R2 (kΩ) Squelch The squelch function disables the data outputs by forcing OUT- low and OUT+ high during a LOS condition. This function ensures that when there is a loss of signal, the limiting amplifier (and all downstream devices) does not respond to input noise or corrupt data. Connect SQUELCH to GND or leave it unconnected to disable squelch. Connect SQUELCH to VCC to enable data squelching.
PAGE 8
+3.0V to +5.
PAGE 9
+3.0V to +5.5V, 125Mbps to 266Mbps Limiting Amplifiers with Loss-of-Signal Detector QSOP.EPS PACKAGE OUTLINE, QSOP .150", .025" LEAD PITCH 21-0055 F 1 1 _______________________________________________________________________________________ 9 MAX3964A/MAX3968 Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.
PAGE 10
Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) 24L QFN THIN.EPS MAX3964A/MAX3968 +3.0V to +5.5V, 125Mbps to 266Mbps Limiting Amplifiers with Loss-of-Signal Detector PACKAGE OUTLINE, 12, 16, 20, 24, 28L THIN QFN, 4x4x0.
PAGE 11
+3.0V to +5.5V, 125Mbps to 266Mbps Limiting Amplifiers with Loss-of-Signal Detector PACKAGE OUTLINE, 12, 16, 20, 24, 28L THIN QFN, 4x4x0.8mm 21-0139 E 2 2 Revision History Rev 0; 10/98: Initial data sheet release. Rev 1; 10/02: Added MAX3964ETP. Rev 2; 5/03: Added package code for TQFN (page 1); updated package drawing (pages 11, 12). Rev 3; 9/04: Added MAX3964A (pages 1 to 13). Rev 4; 2/06: Added lead-free package information to Ordering Information table (page 1).