MAXIM MAX6960, MAX6963 Technical data

General Description

The MAX6960–MAX6963 are compact cathode-row display drivers that interface microprocessors to 8 x 8 dotmatrix red, green, and yellow (R,G,Y) LED displays through a high-speed 4-wire serial interface.

The MAX6960–MAX6963 drive two monocolor 8 x 8 matrix displays, or a single RGY 8 x 8 matrix display with no external components. The driver can also be used with external pass transistors to control red, green, blue (RGB) and other displays at higher currents and voltages.

The MAX6960–MAX6963 feature open- and short-circuit LED detection, and provide both analog and digital tile segment current calibration to allow 8 x 8 displays from different batches to be compensated or color matched.

A local 3-wire bus synchronizes multiple interconnected MAX6960–MAX6963s and automatically allocates memory map addresses to suit the user’s display-panel architecture.

The MAX6960–MAX6963s’ 4-wire interface connects multiple drivers, with display memory mapping shared and allocated among the drivers. A single global write operation can send a command to all MAX6960s in a panel.

The MAX6963 drives monocolor displays with two-step intensity control. The MAX6962 drives monocolor displays with two-step or four-step intensity control. The MAX6961 drives monocolor or RGY displays with two-step intensity control. The MAX6960 drives monocolor or RGY displays with two-step or four-step intensity control.

Features

♦ 2.7V to 3.6V Operation

♦ High-Speed 20MHz Serial Interface

♦ Trimmed 40mA or 20mA Peak Segment Current

♦ Directly Drives Either Two Monocolor or One RGY

Cathode-Row 8 x 8 Matrix Displays

♦ Analog Digit-by-Digit Segment Current Calibration

♦ Digital Digit-by-Digit Segment Current Calibration

♦ 256-Step Panel Intensity Control (All Drivers)

♦ Four Steps per Color Pixel-Level Intensity Control

♦ Open/Short LED Detection

♦ Burst White to Display Memory Planes

♦ Global Command Access All Devices

♦ Can Control RGB Panels or Higher

Current/Voltage Panels with External Pass Transistors

♦ Multiple Display Data Planes Ease Animation

♦ Automatic Plane Switching from 63 Planes per

Second to One Plane Every 63s, with Interrupt

♦ Slew-Rate-Limited Segment Drivers for Lower EMI

♦ Driver Switching Timing Can Be Spread Between

Multiple Drivers to Flatten Power-Supply Peak Demand

♦ Low-Power Shutdown with Full Data Retention

♦ -40°C to +125°C Temperature Range

MAX6960–MAX6963

4-Wire Serially Interfaced

8 x 8 Matrix Graphic LED Drivers

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

19-3696; Rev 3; 6/07

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.

Pin Configurations continued at end of data sheet.

EVALUATION KIT

AVAILABLE

Pin Configurations

Applications

Message Boards Industrial Controls Gaming Machines Audio/Video Equipment

*EP = Exposed paddle.

TOP VIEW

GND

RISET1

RISET0

ADDCLK

ADDIN

4443424140393837363534

MAX6960-MAX6963

1213141516171819202122

DIN

OSC

GND

DOUT

MQFP

ADDOUTV+COL16

RST

CLK

COL1

COL15

COL2

COL14

COL3

V+

COL13

COL12

COL11

COL10 COL9

V+

COL8

COL7

COL6

COL5

COL4

V+

PART TEMP RANGE PIN-PACKAGE PKG CODE

M A X6 9 6 0AM H -40°C to +125°C 44 MQFP —

M AX6960ATH -40°C to +125°C 44 TQFN - E P * T4477- 3 M A X6 9 6 1AM H -40°C to +125°C 44 MQFP — M AX6961ATH -40°C to +125°C 44 TQFN - E P * T4477-3 M A X6 9 6 2AM H -40°C to +125°C 44 MQFP — M AX6962ATH -40°C to +125°C 44 TQFN - E P * T4477-3 M A X6 9 6 3AM H -40°C to +125°C 44 MQFP — M AX6963ATH -40°C to +125°C 44 TQFN - E P * T4477-3

MAX6960–MAX6963

4-Wire Serially Interfaced 8 x 8 Matrix Graphic LED Drivers

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V+ = 2.7V to 3.6V, TA= T

MIN

to T

MAX

, typical values at V+ = 3.3V, TA= +25°C, unless otherwise noted.) (Note 1)

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.

(Voltage with respect to GND.)

V+ .............................................................................-0.3V to +4V

All Other Pins................................................-0.3V to (V+ + 0.3V)

ROW1–ROW8 Sink Current ..............................................750mA

COL1–COL16 Source Current ...........................................48mA

Continuous Power Dissipation (T

= +70°C) 44-Pin MQFP

(derate 12.7 mW/°C over +70°C)...............................1012mW

44-Pin TQFN

(derate 27mW/°C over +70°C)...................................2162mW

Operating Temperature Range

MIN

to T

MAX

) ..............................................-40°C to +125°C

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

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

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

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Operating Supply Voltage V+ 2.7 3.6 V

Master Clock Frequency f

Dead-Clock Protection Frequency

OSC High Time t

OSC Low Time t

Anode Column Source Current COL1–COL16

Anode Column Source-Current Temperature Variation COL1–COL16

Segment Current Slew Rate ΔI

Shutdown mode, all

SHDN

digital inputs at V+ or GND

Intensity set to full, no display load connected

OSC

= 2.3V, V+ =

LED

3.15V to 3.6V, current = high

SEG

= 2.3V, V+ =

LED

2.7V to 3.6V, current = low

= 2.3V, V+ = 3.15V to 3.6V,

LED

current = high

= 2.2V, V+ = 2.7V to 3.3V,

LED

current = low

/ΔtTA = +25°C 30 mA/µs

SEG

TA = +25°C 250 375

TA = T

= T

MIN

to +85°C 500Shutdown Supply Current I

to T

MAX

600

TA = +25°C 7.5 9

TA = T

= T

MIN

to +85°C 10Operating Supply Current I+

to T

MAX

1.0 8.5 MHz

50 90.5 200 kHz

40 ns

TA = +25°C 38 40 42

TA = T

to +85°C 37 43

MIN

= T

MIN

to T

MAX

37 44

TA = +25°C 19 20 21

TA = T

to +85°C 18.5 21.5

MIN

= T

MIN

to T

MAX

18.5 22.0

200

µA

ppm/°C

MAX6960–MAX6963

4-Wire Serially Interfaced

8 x 8 Matrix Graphic LED Drivers

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(V+ = 2.7V to 3.6V, TA= T

MIN

to T

MAX

, typical values at V+ = 3.3V, TA= +25°C, unless otherwise noted.) (Note 1)

Note 1: All parameters are tested at TA= +25°C. Specifications over temperature are guaranteed by design.

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

LOGIC INPUTS AND OUTPUTS

Input Leakage Current DIN, CLK, CS, OSC, ADDIN, ADDCLK, RST

Logic-High Input Voltage DIN, CLK, CS, OSC, ADDIN, ADDCLK, RST

Logic-Low Input Voltage DIN, CLK, CS, OSC, ADDIN, ADDCLK, RST

DOUT Output Rise and Fall Times t

DOUT Output High Voltage V

DOUT Output Low Voltage V

ADDOUT Output High Voltage V

ADDOUT Output Low Voltage V

ADDCLK Output High Voltage V

ADDCLK Output Low Voltage V

TIMING CHARACTERISTICS

CLK Clock Period t

CLK Pulse-Width High t

CLK Pulse-Width Low t CS Fall to CLK Rise Setup Time t CLK Rise to CS Rise Hold Time t

DIN Setup Time t

DIN Hold Time t

Output Data Propagation Delay t Minimum CS Pulse High t

, I

IHI

ILO

FTDO

OHDOISOURCE

OLDOISINK

OHADOISOURCE

OLADOISINK

OHACKISOURCE

OLACKISINK

CSS

CSH

CSW

= 100pF 10 ns

LOAD

= 20mA

= 20mA 0.3 V

= 500µA

= 500µA 0.3 V

= 2.5mA

= 2.5mA 0.3 V

-100 5 +100 nA

0.7 x V+

0.3 x V+

V+ -

0.3

V+ -

0.3

V+ -

0.3

50 ns

22 ns

12.5 ns

0ns

12.5 ns

10 ns

22 ns

25 ns

MAX6960–MAX6963

4-Wire Serially Interfaced 8 x 8 Matrix Graphic LED Drivers

4 _______________________________________________________________________________________

Typical Operating Characteristics

(TA = +25°C, unless otherwise noted.)

OPERATING SUPPLY CURRENT

vs. TEMPERATURE

MAX6960 toc01

TEMPERATURE (°C)

SUPPLY CURRENT (mA)

925926-7

7.2

7.4

7.6

7.8

8.0

7.0

-40 125

3.6V

3.3V

2.7V

SHUTDOWN SUPPLY CURRENT

vs. TEMPERATURE

MAX6960 toc02

TEMPERATURE (°C)

SUPPLY CURRENT (mA)

925926-7

0.1

0.2

0.3

0.4

-40 125

3.6V

3.3V

2.7V

DEAD-CLOCK OSCILLATOR

vs. SUPPLY VOLTAGE

MAX6960 toc03

SUPPLY VOLTAGE (V)

DEAD-CLOCK OSCILLATOR

3.383.162.942.72

100

2.50 3.60

+25°C

-40°C

+125°C

PEAK-OUTPUT SOURCE CURRENT

vs. SUPPLY VOLTAGE (HIGH-CURRENT MODE)

MAX6960 toc04

SUPPLY VOLTAGE (V)

PEAK-OUTPUT CURRENT (mA)

3.43.12.8

2.5 3.7

2.3V LED

PEAK-OUTPUT SOURCE CURRENT

vs.SUPPLY VOLTAGE (LOW-CURRENT MODE)

MAX6960 toc05

SUPPLY VOLTAGE (V)

PEAK-OUTPUT CURRENT (mA)

3.53.33.12.92.7

2.5 3.7

2.2V LED

PEAK-OUTPUT SOURCE CURRENT

vs. TEMPERATURE (HIGH-CURRENT MODE)

MAX6960 toc06

TEMPERATURE (°C)

PEAK-OUTPUT CURRENT (mA)

925926-7

39.6

40.0

40.4

40.8

39.2

-40 125

2.3V LED

3.6V

3.3V

3.15V

Typical Operating Characteristics

MAX6960–MAX6963

4-Wire Serially Interfaced

8 x 8 Matrix Graphic LED Drivers

_______________________________________________________________________________________ 5

Pin Description

MQFP TQFN

1, 6, 11,

12, 44

2–5, 7–10 2–5, 7–10 ROW1–ROW8 LE D C athod e D r i ver s. ROW 1 to RO W 8 outp uts si nk cur r ent fr om the d i sp l ay' s cathod e r ow s.

13 13 OSC Multiplex Clock Input. Drive OSC with a 1MHz to 8.5MHz CMOS clock.

14 14 CS

15 15 DIN Serial-Data Input. Data from DIN loads into the internal shift register on CLK's rising edge.

16 16 DOUT Serial-Data Output. The output is tri-state.

17 17 CLK Serial-Clock Input. On CLK's rising edge data shifts into the internal shift register.

18 18 RST

19, 20,

21, 23–27, 29–33, 35, 36,

22, 28,

34, 38

39 39 ADDOUT

40 40 ADDIN

41 41 ADDCLK

1, 6, 11,

12, 44

19, 20,

21, 23–27, 29–33, 35, 36,

22, 28,

34, 38

NAME FUNCTION

GND Ground

Chip-Select Input. Serial data is loaded into the shift register when CS is low. Data is loaded into the data latch on CS's rising edge.

Reset Input. Hold RST low until at least 50ms after all interconnected MAX6960s are powered up.

COL1–COL16

V+

LED Anode Drivers. COL1 to COL16 outputs source current into the display's anode columns.

Positive Supply Voltage. Bypass V+ to GND with a single 47µF bulk capacitor per chip plus a 0.1µF ceramic capacitor per V+.

Address-Data Output. Connect ADDOUT to ADDIN of the next MAX6960. Use ADDOUT of the last MAX6960 as a plane change interrupt output.

Address-Data Input. For first MAX6960, connect ADDIN to V+. For other MAX6960s, connect ADDIN to ADDOUT of the preceding MAX6960.

Address-Clock Input/Output. Connect ADDCLK of all MAX6960 drivers together, ensuring that only one MAX6960's ADDIN input is connected to V+.

Digit 0 Current Setting. Connect RISET0 to GND to program all of digit 0's segment

42 42 RISET0

43 43 RISET1

— EP EP Exposed Pad on Package Underside. Connect to GND.

currents to 40mA. Leave RISET0 open circuit to program all of digit 0's segment currents to 20mA. Connect RISET0 to GND through a fixed or variable resistor to adjust all of digit 0's segment currents between 20mA and 40mA.

Digit 1 Current Setting. Connect RISET1 to GND to program all of digit 1's segment currents to 40mA. Leave RISET1 open circuit to program all of digit 1's segment currents to 20mA. Connect RISET1 to GND through a fixed or variable resistor to adjust all of digit 1's segment currents between 20mA and 40mA.

MAX6960–MAX6963

4-Wire Serially Interfaced 8 x 8 Matrix Graphic LED Drivers

6 _______________________________________________________________________________________

Quick-Start Guide

Selecting the Appropriate Driver

The MAX6960–MAX6963 matrix LED drivers are available in four versions, with different levels of functionality (Table 1). The two-part ID bits in the fault and device ID register (Table 32) identify the driver type to the interface software. The ID bits may be of use if the same panel software is used to drive more than one type of display panel, because the software can automatically detect the panel type.

This data sheet uses the generic name MAX6960 to refer to the family of four parts MAX6960 through MAX6963, unless there is a specific difference to discuss.

The purpose of this quick-start guide is to provide an overview of the capabilities of the MAX6960 so that the driver can be easily evaluated for a particular application, without fighting through a complex data sheet.

Terminology

• Pixel: One “point” on a display. Comprises one LED for a monocolor display, two LEDs for an RGY display, and three LEDs for an RGB display.

• Monocolor: Display has only one color, typically red for low-cost signs or orange for traffic signs. Varying the current through the LED changes the intensity of the red.

Table 1. Levels of Functionality

Table 2. Maximum Display Matrix on a Single 4-Wire Interface

Table 3. 4-Wire Interface Speed Requirements for Animation

*When operated per Figure 17.

AVAILABLE FUNCTIONS

PART

MAX6960 √√√ √ √ √None.

MAX6961 — √ — √ — √

MAX6962 √√—— √√

MAX6963 — √ —— — √

RGB 2

BITS PER

PIXEL*

RGB

1 BIT PER

PIXEL*

RGY

2 BITS PER

PIXEL

RGY

1 BIT PER

PIXEL

MONOCOLOR

2 BITS PER

PIXEL

MONOCOLOR

1 BIT PER

PIXEL

PI bit (bit D7) in global panel configuration register is fixed at 0 (Table 22).

C bit (bit D6) in global panel configuration register is fixed at 0 (Table 21).

C bit (bit D6) in global panel configuration register is fixed at 0 (Table 21). PI bit (bit D7) in global panel configuration register is fixed at 0 (Table 22).

DISPLAY CONFIGURATION MAXIMUM PIXEL COUNT EXAMPLE MAXIMUM PANEL (PIXELS)

Monocolor 32,768 256 x 128

RGY 16,384 256 x 64

RGB 32,768 (3 buses required; see Figure 17) 128 x 85

256 DRIVERS ON 4-WIRE INTERFACE, 50 FRAMES PER SECOND UPDATE RATE

DISPLAY-MEMORY-ACCESS METHOD

8-bit indirect display memory addressing 1.64 3.28 24-bit direct display memory addressing 4.92 9.83

1-BIT-PER-PIXEL INTENSITY

CONTROL (Mbps)

2-BITS-PER-PIXEL INTENSITY

CONTROL (Mbps)

MAX6960–MAX6963

4-Wire Serially Interfaced

8 x 8 Matrix Graphic LED Drivers

_______________________________________________________________________________________ 7

• Bicolor: Literally means two color, and usually refers to LEDs built with two LED dice of different colors, typically red and green or red and orange/yellow.

• Tricolor: Literally means three color, and can refer to LEDs built with three LED dice of different colors, typically red, green, and blue. The term is also used to refer to a display built with bicolor LEDs, because there are three main colors available (red, green, yellow).

• RGY: Display uses one red LED (R) and one green LED (G) per pixel. When both red and green LEDs are lit, the resulting color is yellow (Y). Varying the current through the LEDs changes the intensity of the pixel and changes the color from red through shades of orange and yellow to green.

• RGB: Display uses one red LED (R), one green LED (G), and one blue LED (B) per pixel. Varying the current through the LEDs changes the intensity of the pixel and changes the color through many shades limited by the current control resolution.

MAX6960 Applications

The MAX6960 is a multiplexed, constant-current LED driver intended for high-efficiency indoor signage and message boards.

The high efficiency arises because the driver operates from a 3.3V nominal supply with minimal voltage headroom required across the driver output stages. The problem of removing heat from even a small display is therefore minimized.

The maximum peak LED drive current is 40mA, which when multiplexed eight ways, provides an average current of 5mA per LED. This current drive is expected to be adequate for indoor applications, but inadequate for outdoor signs operating in direct sun.

The MAX6960 directly drives monocolor (typically red or orange/yellow) or RGY (typically red/green or red/yellow) graphic displays using LEDs with a forward voltage drop up to 2.5V. Blue LEDs and some green LEDs cannot be driven directly because of their high forward voltage drop (around 3.5V to 4.5V). For these displays, the MAX6960 can be used as a graphic controller, just as it can be used for applications requiring higher peak segment currents, and in RGB panels needing a higher driver voltage for the blue LEDs. In these cases, the MAX6960 can be used with external drive transistors to control anode-row displays, with all driver features including pixel-level intensity control still available (see the Applications Information section and Figure 17).

Display Intensity Control

Five levels of intensity control are provided:

• A 256-step PWM panel intensity adjustment sets all MAX6960s simultaneously as a global panel brightness control (Table 27). The 256-step resolution is fine enough to allow fade-in/fade-out graphic effects, as well as provide a means for compensating a panel for background lighting.

• A 2-bits-per-pixel intensity control allows four brightness levels to be set independently per pixel. The pixel-level intensity control can be set to be either arithmetic (off, 1/3, 2/3, full) or geometric (off, 1/4, 1/2, full) for full flexibility (Table 24), and allows four colors to be displayed on monocolor panels, or 16 colors to be displayed on RGY panels, or 64 colors to be displayed on RGB panels.

• The LED drive current can be selected between either a 40mA peak per segment and a lower 20mA peak current on a digit-by-digit basis using the R

ISET0

and R

ISET1

pins. The lower (20mA) current may be the better choice to drive high-efficiency displays, and this setting allows the MAX6960 to operate from a supply voltage as low as 2.7V.

• The LED drive current can be adjusted between 40mA and 20mA peak current on a digit-by-digit basis using fixed or adjustable resistors connected from the R

ISET0

and R

ISET1

pins to GND. These controls enable analog relative adjustments in digit intensity, typically to calibrate digits from different batches, or to color balance RGY displays.

• The digit intensity controls allow each digit’s operating current to be scaled down in 256 steps from the global panel intensity adjustment. The effective operating current for each digit becomes n/256th of the panel intensity value. These controls enable digital relative adjustments in digit intensity in addition to the analog approach outlined above.

Display Size Limitations

The maximum display size that can be handled by a single 4-wire serial interface is given in Table 2, which is for the maximum 256 interconnected MAX6960s. Larger display panels can be designed using a separate CS line for each group of (up to) 256 MAX6960s. Each group would also have its own local 3-wire bus to allocate the driver addresses. The 4-wire interface speeds requirement when continuously updating display memory for high-speed animations is given in Table 3.

MAX6960–MAX6963

4-Wire Serially Interfaced 8 x 8 Matrix Graphic LED Drivers

8 _______________________________________________________________________________________

Software Control

The hardware features are designed to simplify the software interface and eliminate software timing dependencies:

• Two or four planes of display memory are stored, allowing images to be preloaded into the MAX6960– MAX6963 frame memory.

• Animation timing is built in, sequencing through the two or four planes automatically. System software has to update the upcoming plane(s) with new data ahead of time, but do not be concerned about exact timing. The frame rate is adjustable to as fast as 63 frames a second for animations, or to as slow as one frame change every 63s for advertising sequencing.

• Multiple MAX6960s interconnect and share display memory so that the software “sees” the display as memory-mapped planes of contiguous RAM.

• Global commands that need to be received and acted on by every MAX6960 in a panel do just that, with one write.

Hardware Design

A MAX6960 normally drives an 8 x 16 LED matrix, comprising 8 cathode rows and 16 anode columns, or 8 anode rows and 16 cathode columns with external drivers.

The MAX6960 standard wiring connection to either two monocolor 8 x 8 digits, or to a single RGY 8 x 8 digit is shown in Table 4. Figure 3 shows the display pin naming. Figures 1 and 2 show example displays with the MAX6960 drivers connecting to monocolor and RGY panels. Figure 4 shows how the display memory maps to the physical pixels on the display panel, provided that the MAX6960 drivers are interconnected correctly in a rasterlike manner from top left of the panel to bottom right.

Detailed Description

Overview

The MAX6960 is an LED display driver capable of driving either two monocolor 8 x 8 cathode-row matrix digits, or a single RGY 8 x 8 cathode-row matrix digit. The architecture of the driver is designed to allow a large graphic

Table 4. Standard Driver Connection to Monocolor and RGY 8 x 8 Displays

*Digit 0 of a monocolor display is called red, and digit 1 is called green in the data sheet.

Figure 1. Monocolor 1-Bit-per-Pixel, 96-Pixel x 32-Pixel Display Example

DRIVER PINS ROW1–ROW8 DRIVER PINS COL1–COL8 DRIVER PINS COL9–COL16

Monocolor digit 0 (red*)

Monocolor digit 1 (green*)

RGY red/green

Digit 0 (red*) rows (cathodes) R1 to R8

Digit 1 (green*) rows (cathodes) R1 to R8

Red/green rows (cathodes) R1 to R8

Digit 0 columns (anodes) C1 to C8

—

Red columns (anodes) C1 toC8Green columns (anodes) C1 to

—

Digit 1 columns (anodes) C1 to C8

DRIVER0

RED

DRIVER6

RED

RED RED

DRIVER1

DRIVER7

DRIVER2

RED RED

DRIVER8

RED RED

DRIVER12

RED

DRIVER18

RED

RED RED

DRIVER13

DRIVER19

DRIVER14

RED RED

DRIVER20

RED RED

DRIVER3

RED RED

DRIVER9

RED RED

DRIVER15

RED RED

DRIVER21

RED RED

DRIVER4

DRIVER10

DRIVER16

DRIVER22

RED RED

DRIVER5

RED

DRIVER11

RED

DRIVER17

RED

DRIVER23

RED

MAX6960–MAX6963

4-Wire Serially Interfaced

8 x 8 Matrix Graphic LED Drivers

_______________________________________________________________________________________ 9

display panel to be driven easily and intuitively by multiple MAX6960s using 8 x 8 cathode-row matrix digits. The MAX6960s in a display-driver design not only share the host 4-wire interface, but they also share a local 3-wire interface that is not connected to the host. The local 3wire interface works with the user’s driver settings to configure all the MAX6960s to appear to the host interface as one contiguous memory-mapped driver.

The pixel level-intensity control uses frame modulation. Pixels are enabled and disabled on a frame-by-frame basis over a 12-frame super frame (Table 5). The effective pixel frame duty cycle within a super frame sets each pixel’s effective intensity. The 12-frame period of a super frame allows arithmetic and geometric intensity scales to be mixed on the same driver. This allows the user to set up an RGY display with a different color scale for red and

Figure 2. RGY 1-Bit-per-Pixel 48-Pixel x 32-Pixel Display Example

Figure 3. 8 x 8 Matrix Pin Assignment

Figure 4. How Plane Memory Across Multiple MAX6960–MAX6963 Maps to Display Pixels

DRIVER0

RED

GREEN GREEN GREEN GREEN GREEN GREEN

DRIVER1

RED

DRIVER2

RED

DRIVER3

RED

DRIVER4

RED

DRIVER5

RED

DRIVER6

RED

GREEN GREEN GREEN GREEN GREEN GREEN

DRIVER12

RED

GREEN GREEN GREEN GREEN GREEN GREEN

DRIVER18

RED

GREEN GREEN GREEN GREEN GREEN GREEN

DRIVER7

RED

DRIVER13

RED

DRIVER19

RED

DRIVER8

RED

DRIVER14

RED

DRIVER20

RED

COLUMN 1

COLUMN 2

COLUMN 3

COLUMN 4

COLUMN 5

COLUMN 6

COLUMN 7

ROW 1 ROW 2

ROW 3 ROW 4 ROW 5 ROW 6 ROW 7 ROW 8

MONOCOLOR

RED

COLUMN 8

ROW 1 ROW 2

ROW 3 ROW 4 ROW 5 ROW 6 ROW 7 ROW 8

DRIVER9

DRIVER15

DRIVER21

DRIVER10

RED

DRIVER16

RED

DRIVER22

RED

COLUMN 1 (RED)

COLUMN 9 (GREEN)

RGY

DRIVER11

RED

DRIVER17

RED

DRIVER23

RED

FIRST DISPLAY PIXEL MAPS TO FIRST PLANE

LAST DISPLAY PIXEL

MAPS TO LAST PLANE

MEMORY LOCATION

MAX6960–MAX6963

4-Wire Serially Interfaced 8 x 8 Matrix Graphic LED Drivers

10 ______________________________________________________________________________________

green. The MAX6960 uses display memory planes to store the display images. A memory plane is the exact amount of memory required to store the display image. The memory plane architecture allows one plane to be used to refresh the display, while at least one other plane is available to build up the next image. The global plane counter register (Table 30) allows the plane used to refresh the display to be selected either directly on command, or automatically under MAX6960 control. Automatic plane switching can be set from 63 plane changes a second to one plane change every 63s.

Display Memory Addressing

The MAX6960 contains 64 bytes of display mapping memory. This display memory provides four memory planes (of 16 bytes) when 1-bit-per-pixel intensity control is selected, or two memory planes (of 32 bytes) when 2-bits-per-pixel intensity control is used (Table 6). The 64 bytes of display memory in a MAX6960 could be accessed with 6 bits of addressing on a driver-bydriver basis.

The MAX6960 uses a 14-bit addressing scheme. The address map encompasses up to 256 MAX6960 drivers, all connected to the host through a common 4wire interface, and also interconnected through a local 3-wire interface. The purpose of the 3-wire interface is to actively segment the 14-bit address space among the (up to) 256 MAX6960s.

The total display memory is already partitioned among these MAX6960 drivers in a register format. The MAX6960s repartition these registers to appear as contiguous planes of display memory, organized by color (red, then green) and then into planes (P0 to P4) (Table 6).

The MAX6960 accepts 8-bit, 16-bit, and 24-bit transmissions. All MAX6960s sharing an interface receive and decode all these transmissions, but the content of a transmission determines which MAX6960s store and use a particular transmission, and which discard it (Table 7).

Table 5. Frame Modulation with Pixel Intensity

Table 6. Panel Configuration

PIXEL

GRADUATION

Both 1 1 Full 1 1 1 1 1 1 1 1 1 1 1 1

Arithmetic 1 0 2/3 1 0 1 1 0 1 1 0 1 1 0 1

Geometric 1 0 1/2 1 0 1 0 1 0 1 0 1 0 1 0

Arithmetic 0 1 1/3 0 1 0 0 1 0 0 1 0 0 1 0

Geometric 0 1 1/4 0 1 0 0 0 1 0 0 0 1 0 0

Both 0 0 Off 0 0 0 0 0 0 0 0 0 0 0 0

BIT BIT

PIXEL

INTENSITY

SETTING

GLOBAL PANEL CONFIGURATION

PLANES/INTENSITY

(PI BIT)

0 0 1 bit per pixel Monocolor 16 red contiguous 4

0 1 1 bit per pixel RGY

1 0 2 bits per pixel Monocolor

COLOR

(C BIT)

PIXEL-LEVEL

INTENSITY

CONTROL

PATTERN OF MULTIPLEX CYCLES FOR WHICH A PIXEL IS ENABLED

01234567891011

DISPLAY TYPE

DISPLAY MAPPING

ADDRESSES PER PLANE

8 red contiguous, 8 green contiguous

16 red contiguous, 16 red contiguous

DISPLAY

PLANES

AVAILABLE

1 1 2 bits per pixel RGY

16 red (2 noncontiguous groups of 8), 16 green (2 noncontiguous groups of 8)

MAX6960–MAX6963

4-Wire Serially Interfaced

8 x 8 Matrix Graphic LED Drivers

______________________________________________________________________________________ 11

8-Bit Transmissions

Eight-bit transmissions are write-only, data-only accesses that write data to the display memory indirected by the global display indirect address register (Figure 6). The global display indirect address register autoincrements after the write access. Eight-bit transmissions provide the quickest method of updating a plane of display memory of the MAX6960. It is the most suitable display update method if the host system builds an image in local memory, and then dumps the image into a display plane of the MAX6960.

16-Bit Transmissions

Sixteen-bit transmissions are read/write, commandand-data accesses to the MAX6960’s configuration registers (Figure 7). A write can generally be global (updates all MAX6960s on the 4-wire bus with the same

data) or specific (updates just the MAX6960 indirected by the global driver indirect address register). Note:

The global driver indirect address register selects a specific MAX6960. This is not the same as the global display indirect address register, which points to display memory that could be in any MAX6960. A

16-bit read is always indirected through the global driver indirect address register to select only one MAX6960 to respond. When a read or write is indirected through the global driver indirect address register, the 16-bit command can choose whether the global driver indirect address is autoincremented after the command has been executed. This allows the host to set up one or more registers in consecutive MAX6960s with the display indirect address, autoincrementing only when required.

Table 7. Register Addressing Modes

8-, 16-, OR 24-BIT DATA PACKET SENT TO MAX6960

DATA FORMAT

D23

D22

D21

D20

D19

D18

D17

D16

D15

D14

8-bit indirect display memory addressing. Address is global display indirect address (14 bits) stored as {MSB, LSB} in {register 0x0A, register 0x09}.

16-bit device addressing. — R/W AI L/G 0

Factory reserved; do not write to this address.

24-bit direct display memory addressing (monocolor 1 bit per pixel).

24-bit direct display memory addressing (RGY 1 bit per pixel).

R/W X

Planes

0, 1, 2, 3

Planes

0, 1, 2, 3

—1 —

12-bit addressing across 256 drivers, 4096 x 8 red pixels

12-bit addressing across 256 drivers, 2048 x 8 red pixels, and 2048 x 8 green pixels

— 8 bits of display memory

D13

D12

D11

D10

4-bit

address

8 bits of driver register data

8 bits of display memory (1 bit per pixel)

24-bit direct display memory addressing (monocolor 2 bits per pixel).

24-bit direct display memory addressing (RGY 2 bits per pixel).

R/W X

Planes

0, 1

Planes

0, 1

13-bit addressing across 256 drivers, 4096 x 4 red pixels

13-bit addressing across 256 drivers, 4096 x 4 red pixels, and 4096 x 4 green pixels

8 bits of display memory (2 bits per pixel)

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