MAX11501USA+T - Maxim Integrated Products, Inc.

General Description

The MAX11501/MAX11502 integrated filters offer three

channels of 5th-order filters for standard-definition

video and include +6dB output buffers on each chan-

nel. These video filters are ideal for anti-aliasing and

DAC smoothing in applications such as set-top boxes,

security systems, digital video recorders (DVRs), DVD

players, and personal video recorders.

The MAX11501/MAX11502 video inputs feature a trans-

parent clamp compatible with AC- and DC-coupled

input signals and allow DAC outputs to be directly cou-

pled. The 5th-order filters provide a typical -3dB band-

width of 8.6MHz (MAX11501) and 8.9MHz (MAX11502)

and offer either a flat passband response (MAX11501)

or a +0.8dB peaking passband response (MAX11502)

on all channels.

Each channel includes an output buffer with a gain of

+6dB capable of driving a full 2VP-P video signal into

two standard 150Ω(75Ωback-terminated) video loads.

The buffers drive either AC- or DC-coupled loads and

assure a blanking level of below 1V after the back-

match resistor.

The MAX11501/MAX11502 operate from a single +5V

supply and are available in the upper commercial 0°C

to +85°C temperature range. These devices are avail-

able in small 8-pin SO packages.

Applications

Set-Top Box Receivers

Digital Video Recorders (DVRs)

Security Video Systems

SDTV

DVD Players

Personal Video Recorders

Video On-Demand

Features

oThree-Channel 5th-Order 9MHz Filter for

Standard-Definition Video

o+6dB Output Buffers

oTransparent Input Clamp

oAC- or DC-Coupled Inputs

oAC- or DC-Coupled Outputs

oFlat Passband Response (MAX11501)

o+0.8dB Peaking Passband Response (MAX11502)

on All Channels

o12kV HBM ESD Protection on Outputs

oSingle +5V Power Supply

oSmall 8-Pin SO Package

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

________________________________________________________________

Maxim Integrated Products

19-3002; Rev 1; 4/08

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

EVALUATION KIT

AVAILABLE

Ordering Information

Denotes a lead-free package.

Note: All devices are specified over the 0°C to +85°C operat-

ing temperature range.

PART PIN-

PACKAGE

FREQUENCY

RESPONSE

MAX11501USA+ 8 SO Flat

MAX11502USA+ 8 SO HF Boost

Typical Operating Circuit and Pin Configuration appear at end

of data sheet.

MAX11501

MAX11502

OUT1

+6dB

BUFFERTRANSPARENT

CLAMP

9MHz 5TH-ORDER

BUTTERWORTH

FILTER

IN1

OUT2

+6dB

IN2

OUT3

+6dB

IN3

VCC

GND

Block Diagram

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(VCC = +5V, RLOAD = 150Ωto GND, CIN = 0.1µF, TA= 0°C to +85°C, frequency response is relative to 100kHz, unless otherwise noted.)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional

operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to

absolute maximum rating conditions for extended periods may affect device reliability.

VCC to GND..............................................................-0.3V to +6V

All other pins to GND ...-0.3V to the lower of (VCC + 0.3V) and +6V

Continuous Power Dissipation (TA= +70°C)

8-Pin SO (derate 5.9mW/°C above +70°C)................. 470mW

Maximum Current into any Pin Except VCC and GND......±50mA

Operating Temperature Range

MAX1150_USA+ .................................................0°C to +85°C

Storage Temperature Range .............................-65°C to +150°C

Lead temperature (soldering, 10s) ..................................+300°C

Junction Temperature......................................................+150°C

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

MAX11501 4.5 7.2

-1dB Bandwidth f1dB MAX11502 5 7.8 MHz

MAX11501 8.6

-3dB Bandwidth f3dB MAX11502 8.9 MHz

MAX11501, f = 27MHz 50

Stopband Attenuation ASB MAX11502, f = 27MHz 48 dB

Low-Frequency Gain AV5.8 6.0 6.2 dB

Low-Frequency Gain Match AV

(

MATCH

)

0.02 dB

Input Voltage Range VIN Referenced to GND if DC-coupled 1.4 V

Differential Gain dG All channels 0.1 %

Differential Phase dφAll channels 0.3 Degrees

Total Harmonic Distortion THD VOUT = 1.8VP-P, f = 1MHz (all channels) 0.1 %

Channel-to-Channel Crosstalk XTALK f = 1MHz -80 dB

Signal-to-Noise Ratio SNR NTC-7 weighting, 100kHz, 4.2MHz 80 dB

Propagation Delay tPD f = 4.5MHz 76 ns

Supply Voltage Range VDD 4.75 5 5.25 V

Supply Current ICC No load 18 26 mA

Power-Supply Rejection Ratio PSRR DC (all channels) 60 dB

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

_______________________________________________________________________________________

MAX11501

FREQUENCY RESPONSE

MAX11501 toc01

FREQUENCY (MHz)

RESPONSE (dB)

101

-60

-50

-40

-30

-20

-10

-70

0.1 100

MAX11501

PASSBAND RESPONSE

MAX11501 toc02

FREQUENCY (MHz)

RESPONSE (dB)

-3

0.1 10

MAX11501

GROUP DELAY

MAX11501 toc03

FREQUENCY (MHz)

DELAY (ns)

101

100

120

0.1 100

MAX11501

DIFFERENTIAL GAIN, NTSC

MAX11501 toc04

STEP

DIFFERENTIAL GAIN (%)

65432

-0.1

0.1

0.2

-0.2

MAX11501

DIFFERENTIAL PHASE, NTSC

MAX11501 toc05

STEP

DIFFERENTIAL PHASE (deg)

65432

0.1

0.2

0.3

0.4

-0.1

MAX11501

2T RESPONSE

MAX11501 toc06

CH1 = INPUT

CH2 = OUTPUT, AFTER BACKMATCH RESISTOR

CH2

CH1

200ns/div

MAX11501

MODULATED 12.5T RESPONSE

MAX11501 toc07

CH1 = INPUT

CH2 = OUTPUT, AFTER BACKMATCH RESISTOR

CH2

CH1

400ns/div

MAX11501

MULTIBURST RESPONSE

MAX11501 toc08

CH1 = INPUT

CH2 = OUTPUT, AFTER BACKMATCH RESISTOR

CH2

CH1

10μs/div

MAX11502

FREQUENCY RESPONSE

MAX11501 toc09

FREQUENCY (MHz)

RESPONSE (dB)

101

-60

-50

-40

-30

-20

-10

-70

0.1 100

Typical Operating Characteristics

(VCC = 5V, RL= 150Ωto GND, output DC-coupled, TA= +25°C.)

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

4 _______________________________________________________________________________________

MAX11502

PASSBAND RESPONSE

MAX11501 toc10

FREQUENCY (MHz)

RESPONSE (dB)

-3

0.1 10

MAX11502

GROUP DELAY

MAX11501 toc11

FREQUENCY (MHz)

DELAY (ns)

101

100

120

0.1 100

MAX11502

DIFFERENTIAL GAIN, NTSC

MAX11501 toc12

STEP

DIFFERENTIAL GAIN (%)

65432

-0.1

0.1

0.2

-0.2

MAX11502

DIFFERENTIAL PHASE, NTSC

MAX11501 toc13

STEP

DIFFERENTIAL PHASE (deg)

65432

0.1

0.2

0.3

0.4

-0.1

MAX11502

2T RESPONSE

MAX11501 toc14

CH1 = INPUT

CH2 = OUTPUT, AFTER BACKMATCH RESISTOR

CH2

CH1

200ns/div

MAX11502

MODULATED 12.5T RESPONSE

MAX11501 toc15

CH1 = INPUT

CH2 = OUTPUT, AFTER BACKMATCH RESISTOR

CH2

CH1

400ns/div

MAX11502

MULTIBURST RESPONSE

MAX11501 toc16

CH1 = INPUT

CH2 = OUTPUT, AFTER BACKMATCH RESISTOR

CH2

CH1

10μs/div

Typical Operating Characteristics (continued)

(VCC = 5V, RL= 150Ωto GND, output DC-coupled, TA= +25°C.)

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

_______________________________________________________________________________________ 5

Detailed Description

Each channel of the MAX11501/MAX11502 contains a

transparent input clamp, an 8.6MHz (MAX11501) or

8.9MHz (MAX11502), 5th-order lowpass filter and an

output amplifier with a gain of two (see the

Typical

Operating Circuit

). The MAX11501 provides a flat pass-

band response and the MAX11502 features a +0.8dB

high-frequency boost at 5MHz on all channels to help

with system roll-off. Within the passband, each channel

amplifies the signal by two and adds 280mV of offset.

VOUT = (2 x VIN) + 0.28V

Typical voltage levels are shown in Figures 1 and 2.

Inputs

Transparent Clamps

All inputs feature transparent clamps to allow either AC

or DC input coupling. The clamp remains inactive while

the input signal is above ground, offering true DC input

coupling. If the signal goes below ground, as when the

signal is AC-coupled, the internal clamp sets the sync

tip at slightly below the ground level.

INPUT SIGNAL

0.3V

1.0V

0.0V

OUTPUT SIGNAL

0.88V

2.28V

0.28V

IN_ OUT_

MAX11501

MAX11502

Figure 1. Typical AC-Coupled Signal

Pin Description

PIN NAME FUNCTION

1 IN1 Video Input Channel 1

2 IN2 Video Input Channel 2

3 IN3 Video Input Channel 3

CC Power Supply

5 GND Ground

6 OUT3 Video Output Channel 3

7 OUT2 Video Output Channel 2

8 OUT1 Video Output Channel 1

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

6 _______________________________________________________________________________________

Input Coupling

The choice of AC- or DC-coupling the input depends

on the video source. Many DACs provide a current out-

put and are terminated to ground with a resistor. Such

DAC outputs are conveniently DC-coupled to the

MAX11501/MAX11502. Use AC-coupling when the DC

level of the video signal is unknown or outside the

specified input range of the MAX11501/MAX11502,

such as SCART or VCC terminated DAC outputs.

DC-Coupled Inputs

If the input is DC-coupled, the input voltage must

remain above zero but not exceed the maximum input

voltage of 1.4V (typical).

AC-Coupled Inputs

If the input is AC-coupled, the transparent clamps are

active and set the lowest point of the signal at ground.

This is appropriate for unipolar signals such as Y, R, G,

or B, with or without sync pulses (Figure 3).

For bipolar signals such as Pb and Pr, bias the AC-cou-

pled inputs to a fixed DC voltage, typically 0.59V, to ensure

that the transparent clamp remains off. A suitable network

is shown in Figure 4. Determine the bias voltage using:

where ILis the input leakage current (typically 0.5µA).

RR VIR

BCCL

=+×−×

()

12 1

INPUT SIGNAL

0.32V

1.02V

0.02V

0.00V

OUTPUT SIGNAL

0.92V

0.32V

IN_ OUT_

MAX11501

MAX11502

2.32V

Figure 2. Typical DC-Coupled Signal

IN_

MAX11501

MAX11502

0.1μF

ENCODER

DAC

Figure 3. Simple AC-Coupling for Unipolar Signals (Y, R, G, B)

IN_

820kΩ

120kΩ

MAX11501

MAX11502

0.1μF

ENCODER

DAC

VCC

Figure 4. AC-Coupling for Bipolar Signals (Pb, Pr)

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

_______________________________________________________________________________________ 7

Standard-Definition Filters

The MAX11501/MAX11502 filters are optimized to deliver

a flat (MAX11501) or high-frequency boosted (MAX11502)

passband and high stopband attenuation. The filter char-

acteristics have been chosen to provide excellent time

domain response with low overshoot. The typical -3dB fre-

quency of 8.6MHz (MAX11501) and 8.9MHz (MAX11502)

guarantee minimal attenuation in the passband while

at the same time offering a 27MHz attenuation of

typically -50dB (MAX11501) and -48dB (MAX11502).

Output Buffer

The MAX11501/MAX11502 feature output buffers with

+6dB of gain. A typical load (Figure 5(a)) is a 75Ωback-

match resistor, an optional 220µF or larger AC-coupling

capacitor, a transmission line, and a 75Ωtermination

resistor. The MAX11501/MAX11502 clamp the signal,

forcing the blanking level to less than 1V at the termina-

tion resistor. This allows direct drive of video loads at

digital TV specifications without the need for costly AC-

coupling capacitors. The MAX11501/MAX11502 drive

two parallel loads per output (Figure 5(b)), but thermal

considerations must be taken into account when doing

so (see the

Junction-Temperature Calculations

section).

Applications Information

Output Configuration

The MAX11501/MAX11502 outputs may be either DC- or

AC-coupled. When the outputs are AC-coupled, choose

a capacitor that passes the lowest frequency content of

the video signal, and keeps the line-time distortion within

desired limits. The capacitor value is a function of the

input leakage and impedance of the circuit being driven.

The MAX11501/MAX11502 easily drive the industry com-

mon 220µF, or larger, coupling capacitor. If any or all

outputs are driving two parallel loads, see the

Junction-

Temperature Calculations

section.

The MAX11501/MAX11502 outputs are fully protected

against short circuits to ground. The short-circuit pro-

tection circuitry limits the output current to 80mA (typi-

cal) per output. Shorting more than one output to

ground simultaneously may exceed the maximum

package power dissipation.

Junction-Temperature Calculations

Die temperature is a function of quiescent power dissi-

pation and the power dissipation in the output drivers.

Calculate the power dissipated, PD, using:

PD= PDS + PDO1 + PDO2 + PDO3

where PDS is the quiescent power dissipated in the die,

and given by:

PDS = VCC x ICC

and where PDOn is the power dissipated in the nth dri-

ver stage and given by:

where VORMSn is the RMS output voltage and RLn is the

load resistance.

The following is an example of a junction-temperature

calculation, assuming the following conditions:

1) Video standard = 525/60/2:1.

2) Video format = RGB with syncs on all.

3) Picture content = 100% white.

4) The input signal is AC-coupled.

5) The output signal is DC-coupled.

6) VCC = 5.0V.

7) ICC = 26mA.

PVV V

DOn CC ORMSn ORMSn

=−

()

MAX11501

MAX11502

220μF

(OPTIONAL)

75Ω

OUT_

220μF

(OPTIONAL)

75Ω

MAX11501

MAX11502

OUT_

(a) (b)

220μF

(OPTIONAL)

75Ω

Figure 5. Typical Output Loads

MAX11501/MAX11502

A sync tip exists at 280mV and peak white exists at

2.28V. The RMS voltage is approximately 1.88V on

each output (80% of the peak-to-peak voltage, plus the

offset) giving:

PDS = 5 x 0.026 = 0.13W

and

PD= 0.13 + 0.078 + 0.078 + 0.078 = 0.364W

The junction temperature is given by:

TJ= TA+ (RθJA x PD)

where TJis junction temperature, TAis ambient temper-

ature (assume +70°C), and RθJA is thermal resistance

junction to ambient.

From the

Absolute Maximum Ratings

section of the data

sheet, the derating factor is 5.9mW/°C above +70°C.

RθJA = 1/(derating factor) = 1/(5.9mW/°C) = 170°C/W

(derating and maximum power dissipation are based on

minimum PCB copper and indicate worst case).

Therefore:

TJ= 70 + (170 x 0.364) = +132°C

In this example, the die temperature is below the

absolute maximum allowed temperature. It is unlikely

under normal circumstances that the maximum die

temperature will be reached, however it is possible if

tolerances of VCC, RL, input voltage etc. are consid-

ered and the ambient temperature is high.

Changing the above example to a single video load on

each output results in:

TJ= +112°C

PCB Layout Recommendations

To help with heat dissipation, connect the power and

ground traces to large copper areas. Bypass VCC to

GND with 0.1µF and 1.0µF capacitors. Surface-mount

capacitors are recommended for their low inductance.

Place traces carrying video signals appropriately to

avoid mutual coupling. When AC-coupling the inputs,

place the capacitors as close as possible to the device

and keep traces short to minimize parasitic capaci-

tance and inductance. For a recommended PCB lay-

out, refer to the MAX11501/MAX11502 evaluation kit

datasheet.

DOn =−

()

×= . .

5 1 88 1 88

75 0 078

Three-Channel,

Standard-Definition Video Filters

8 _______________________________________________________________________________________

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

_______________________________________________________________________________________ 9

IN1

0.1μF* 220μF*

75Ω75Ω

75Ω

OUT1

GND

*OPTIONAL CAPACITORS

VCC

9MHz 5TH-ORDER

BUTTERWORTH

FILTER

BUFFER

TRANSPARENT

CLAMP

ENCODER

+6dB

MAX11501

MAX11502

DAC

IN2

0.1μF* 220μF*

75Ω75Ω

75Ω

OUT2

+6dB

DAC

IN3

0.1μF* 220μF*

75Ω75Ω

75Ω

OUT3

+5V

+6dB

DAC

Typical Operating Circuit

OUT3

GNDVCC

OUT1

OUT2IN2

IN3

IN1

TOP VIEW

MAX11501

MAX11502

Pin Configuration

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

10 ______________________________________________________________________________________

Package Information

For the latest package outline information, go to www.maxim-ic.com/packages.

PACKAGE TYPE PACKAGE CODE DOCUMENT NO.

8 SO S8+2 21-0041

MAX11501/MAX11502

Three-Channel,

Standard-Definition Video Filters

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are

implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________

Heaney

Revision History

REVISION

NUMBER

REVISION

DATE DESCRIPTION PAGES

CHANGED

0 12/07 Initial release —

1 4/08 Updated Block Diagram 1