Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - display driver LED 7 segments 8 numbers 3-core, Seriell 10 mA QSOP 16

General Description

The MAX6950/MAX6951 are compact common-cathode

display drivers that interface microprocessors to individ-

ual 7-segment numeric LED digits, bar graph, or discrete

LEDs through an SPI™-, QSPI™-, MICROWIRE™-com-

patible serial interface. The supply voltage can be as low

as 2.7V.

The MAX6950 drives up to five 7-segment digits or 40

discrete LEDs. The MAX6951 drives up to eight 7-seg-

ment digits or 64 discrete LEDs.

Included on-chip are hexadecimal character decoders

(0–9, A–F), multiplex scan circuitry, segment and digit

drivers, and a static RAM that stores each digit. The

user may select hexadecimal decoding or no-decode

for each digit to allow any mix of 7-segment digits, bar

graph, or discrete LEDs to be driven. The segment cur-

rent for the LEDs is set by an internal digital brightness

control. The segment drivers are slew-rate limited to

reduce EMI.

Individual digits may be addressed and updated with-

out rewriting the entire display. The devices include a

low-power shutdown mode, digital brightness control, a

scan-limit register that allows the user to display from

one to eight digits, segment blinking that can be syn-

chronized across drivers, and a test mode that forces

all LEDs on.

Applications

Set-Top Boxes

Panel Meters

White Goods

Bar Graphs and Matrix Displays

Industrial Controllers and Instrumentation

Professional Audio Equipment

Medical Equipment

Features

♦ High-speed 26MHz SPI-, QSPI-, MICROWIRE-

Compatible Serial Interface

♦ +2.7V to +5.5V Operation

♦ Individual LED Segment Control

♦ Segment Blinking Control that Can Be

Synchronized Across Multiple Drivers

♦ Hexadecimal Decode/No-Decode Digit Selection

♦ Digital Brightness Control

♦ Display Blanked on Power-Up

♦ Drives Common-Cathode LED Digits

♦ Multiplex Clock Syncronizable to External Clock

♦ Slew-Rate Limited Segment Drivers for Low EMI

♦ 75µA Low-Power Shutdown (Data Retained)

♦ Small 16-Pin QSOP Package

MAX6950/MAX6951

Serially Interfaced, +2.7V to +5.5V,

5- and 8-Digit LED Display Drivers

________________________________________________________________ Maxim Integrated Products 1

DIN V+

(DIG6)/SEG6

DIG4/SEG4

(DIG5)/SEG5

(DIG7)/SEG7

SEG8

OSC

TOP VIEW

MAX6950

MAX6951

QSOP

CLK

DIG3/SEG3

DIG0/SEG0

DIG2/SEG2

DIG1/SEG1

ISET

GND

( ) MAX6951 ONLY

Pin Configuration

19-2227; Rev 2; 3/05

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.

Ordering Information

PART TEMP RANGE PIN-PACKAGE

MAX6950CEE 0°C to +70°C 16 QSOP-EP*

MAX6950EEE -40°C to +85°C 16 QSOP-EP*

MAX6951CEE 0°C to +70°C 16 QSOP-EP*

MAX6951EEE -40°C to +85°C 16 QSOP-EP*

Functional Diagram appears at end of data sheet.

Typical Application appears at end of data sheet.

SPI and QSPI are trademarks of Motorola, Inc.

MICROWIRE is a trademark of National Semiconductor Corp.

*EP = Exposed pad.

EVALUATION KIT

AVAILABLE

Summary of content (19 pages)

PAGE 1
9-2227; Rev 2; 3/05 KIT ATION EVALU E L B A AVAIL Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers Features The MAX6950/MAX6951 are compact common-cathode display drivers that interface microprocessors to individual 7-segment numeric LED digits, bar graph, or discrete LEDs through an SPI™-, QSPI™-, MICROWIRE™-compatible serial interface. The supply voltage can be as low as 2.7V. The MAX6950 drives up to five 7-segment digits or 40 discrete LEDs.
PAGE 2
MAX6950/MAX6951 Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers ABSOLUTE MAXIMUM RATINGS Voltage (with Respect to GND) V+………………………………. ...................................-0.3V to 6V All Other Pins................................................-0.3V to (V+ + 0.3V) DIG1–DIG8 Sink Current.................................................. 440mA SEG1–SEG9 Source Current.............................................. 55mA Continuous Power Dissipation (TA = +70°C) 16-Pin QSOP (derate 8.
PAGE 3
Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers (Typical operating circuit, V+ = +3.0V to +5.5V, TA = TMIN to TMAX, unless otherwise noted.) (Note 1) SYMBOL CONDITIONS Slow Segment Blink Period (Internal Oscillator) PARAMETER fSLOWBLINK Eight digits scanned, OSC = RC oscillator, RSET = 56kΩ, CSET = 27pF 1 s Fast Segment Blink Period (Internal Oscillator) fFASTBLINK Eight digits scanned, OSC = RC oscillator, RSET = 56kΩ, CSET = 27pF 0.
PAGE 4
Typical Operating Characteristics (Typical operating circuit, scan limit set to eight digits, V+ = +3.3V, VLED = 2.4V, TA = +25°C, unless otherwise noted.) INTERNAL OSCILLATOR FREQUENCY vs. TEMPERATURE INTERNAL OSCILLATOR FREQUENCY vs. SUPPLY VOLTAGE V+ = 2.7V 4.20 4.10 V+ = 3.3V 4.00 V+ = 5V 3.90 3.80 3.70 MAX6950/1 toc02 OSCILLATOR FREQUENCY (MHz) 4.30 4.40 OSCILLATOR FREQUENCY (MHz) MAX6950/1 toc01 4.40 4.30 4.20 4.10 4.00 3.90 3.80 3.70 3.60 -40 -20 0 20 60 40 TEMPERATURE (°C) 3.
PAGE 5
Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers PIN NAME FUNCTION 1 DIN Serial Data Input. Data is loaded into the internal 16–bit Shift register on CLK’s rising edge. 2 CLK Serial-Clock Input. On CLK’s rising edge, data is shifted into the Internal Shift register. On CLK’s falling edge, data is clocked out of DOUT. CLK input is active only while CS is low. 3–6, 10–14 DIGX, SEGX Digit X outputs sink current from the display common cathode when acting as digit drivers.
PAGE 6
MAX6950/MAX6951 Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers Table 1.
PAGE 7
Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers MAX6950/MAX6951 tCSW CS tCL tCSS CLK tDS DIN tCH tCSH tCP tDH D15 D14 D1 D0 Figure 1. Timing Diagram CS CLK D15 DIN D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Figure 2. Transmission of 16 Bits to the MAX6950/MAX6951 CS CLK DIN BIT1 BIT2 N-15 N-14 N-13 N-12 N-11 N-10 N-9 N-8 N-7 N-6 N-5 N-4 N-3 N-2 N-1 N Figure 3 .
PAGE 8
MAX6950/MAX6951 Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers Table 3. Register Address Map COMMAND ADDRESS REGISTER No-Op D15 D14 D13 D12 D11 D10 D9 D8 HEX CODE 0 0 0 0 0 0 0 0 0x00 Decode Mode 0 0 0 0 0 0 0 1 0x01 Intensity 0 0 0 0 0 0 1 0 0x02 Scan Limit 0 0 0 0 0 0 1 1 0x03 Configuration Factory reserved. Do not write to this.
PAGE 9
Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers MAX6950/MAX6951 Table 4.
PAGE 10
MAX6950/MAX6951 Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers Table 5. Configuration Register Format REGISTER DATA MODE ADDRESS CODE (HEX) D7 D6 D5 D4 D3 D2 D1 D0 Configuration register 0x04 X X R T E B 0 S D2 D1 D0 Table 6. Shutdown Control (S Data Bit D0) Format MODE ADDRESS CODE (HEX) REGISTER DATA D7 D6 D5 D4 D3 Shutdown 0x04 X X R T E B 0 0 Normal operation 0x04 X X R T E B 0 1 Table 7.
PAGE 11
Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers MAX6950/MAX6951 Table 10. Global Clear Digit Data (R Data Bit D5) Format REGISTER DATA ADDRESS CODE (HEX) D7 D6 D5 D4 D3 D2 D1 D0 Digit data for both planes P0 and P1 are unaffected 0x04 X X 0 T E B 0 S Digit data for both planes P0 and P1 are cleared on the rising edge of CS 0x04 X X 1 T E B 0 S D7 D6 D5 D4 D3 D2 D1 D0 MODE Table 11.
PAGE 12
MAX6950/MAX6951 Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers Table 13. Intensity Register Format D4 D3 D2 D1 D0 HEX CODE X X 0 0 0 0 0xX0 X X 0 0 0 1 0xX1 X X 0 0 1 0 0xX2 X X 0 0 1 1 0xX3 X X 0 1 0 0 0xX4 X X X 0 1 0 1 0xX5 X X X 0 1 1 0 0xX6 X X X X 0 1 1 1 0xX7 DUTY CYCLE TYPICAL SEGMENT CURRENT (mA) ADDRESS CODE (HEX) 1/16 (min on) 2.5 0x02 X X 2/16 5 0x02 X X 3/16 7.
PAGE 13
Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers MAX6950/MAX6951 START OF NEXT ONE COMPLETE 1.
PAGE 14
MAX6950/MAX6951 Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers Table 14.
PAGE 15
Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers REGISTER DATA Segment line D7 D6 D5 D4 D3 D2 D1 D0 dp a b c d e f g a f b g e c d d KF = 6720 RSET = external resistor in kΩ CSET = external capacitor in pF CSTRAY = stray capacitance from OSC pin to GND in pF, typically 3pF The recommended value of RSET is 56kΩ and the recommended value of CSET is 27pF.
PAGE 16
MAX6950/MAX6951 Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers Table 17. Digit Register Mapping with Blink Globally Disabled SEGMENT’S BIT SETTING IN PLANE P1 X X SEGMENT’S BIT SETTING IN PLANE P0 0 1 SEGMENT BEHAVIOR Segment off during both halves of each blink period Segment off during both halves of each blink period Table 18.
PAGE 17
Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers 3.3V C2 22µF C1 100nF 16 9 DIG1–DIG8 SEG1–SEG9 8 DIGITS AND SEGMENTS (SEE TABLE 1 FOR CONNECTIONS) MAX6951 µC ISET DIN CS CLK 1 15 2 7 DIN RSET 56kΩ CS OSC CLK 9 CSET 27pF 8 Chip Information TRANSISTOR COUNT: 17,350 PROCESS: CMOS Figure 5.
PAGE 18
Serially Interfaced, +2.7V to +5.
PAGE 19
Serially Interfaced, +2.7V to +5.5V, 5- and 8-Digit LED Display Drivers QSOP.EPS 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.