View ST2225A_290169.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

ST2225A
Version Issue Date File Name Total Pages : A.025 : 2001/11/26 : SP-ST2225A-A.025.doc : 12
LED Display Driver
9 7 1
SILICON TOUCH TECHNOLOGY INC.
9-7F-1, Prosperity Road I, Science Based Industrial Park, Hsin-Chu, Taiwan 300, R.O.C. Fax886-3-5645626 Tel886-3-5645656
SILICON TOUCH TECHNOLOGY INC.
ST2225A
ST2225A LED Display Driver
General Description
The ST2225A LED display driver is a monolithic CMOS IC. In order to achieve continuous brightness control, the LED display brightness is controlled by setting a reference current through a variable resistor connected between a supply and a single pin.
Features
n"
Continuous brightness control Serial data input No load signal required for data latch Wide power supply operation TTL compatibility 35 outputs, 20mA capability Small package, SSOP48 and bare chip form
n"
n"
n"
n"
n"
n"
Applications
n"
Industrial control indicator Relay driver Digital clock, thermometer, counter, voltmeter Instrumentation readouts
n"
n"
n"
Ordering Information
Part Number ST2225A-SS3 ST2225A-D
LED Display Driver
Temp. Range -40 to +85 -40 to +85
-1-
Package SSOP48 Bare Chip
VersionA.025
SILICON TOUCH TECHNOLOGY INC.
ST2225A
Block Diagram
VDD BRIGHTNESS CONTROL 21 22 OUT35 30 OUT1 19
35 OUTPUT BUFFERS
DATA ENABLE SERIAL DATA CLOCK
29 28 27
35 LATCHES 35-BIT SHIFT REGISTERS
LOAD
RESET
20
RESET 1,13,36
Figure 1
Connection Diagram : SSOP48 Package
VSS OUTPUT BIT17 OUTPUT BIT16 OUTPUT BIT15 OUTPUT BIT14 OUTPUT BIT13 OUTPUT BIT12 OUTPUT BIT11 OUTPUT BIT10 OUTPUT BIT 9 OUTPUT BIT 8 OUTPUT BIT 7 VSS OUTPUT BIT 6 OUTPUT BIT 5 OUTPUT BIT 4 OUTPUT BIT3 OUTPUT BIT 2 OUTPUT BIT 1 RESET BRIGHTNESS CONTROL VDD N/A N/A 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 OUTPUT BIT18 OUTPUT BIT19 OUTPUT BIT20 OUTPUT BIT21 OUTPUT BIT22 OUTPUT BIT23 OUTPUT BIT24 OUTPUT BIT25 OUTPUT BIT26 OUTPUT BIT27 OUTPUT BIT28 OUTPUT BIT29 VSS OUTPUT BIT30 OUTPUT BIT31 OUTPUT BIT32 OUTPUT BIT33 OUTPUT BIT34 OUTPUT BIT35 DATA ENABLE DATA CLOCK N/A N/A
Figure 2 LED Display Driver -2VersionA.025
ST2225A-SS3
SILICON TOUCH TECHNOLOGY INC.
ST2225A
Die Configuration
OUTPUT BIT 14 OUTPUT BIT 15 OUTPUT BIT 16 OUTPUT BIT 17 OUTPUT BIT 18 OUTPUT BIT 19 OUTPUT BIT 20 OUTPUT BIT 21 OUTPUT BIT 22 OUTPUT BIT 23 OUTPUT BIT 24 OUTPUT BIT 25 OUTPUT BIT 26 OUTPUT BIT 27 OUTPUT BIT 28 OUTPUT BIT 29 VSS OUTPUT BIT 30 OUTPUT BIT 31 OUTPUT BIT 32 OUTPUT BIT 33 OUTPUT BIT 34 OUTPUT BIT 35
OUTPUT BIT 13 OUTPUT BIT 12 OUTPUT BIT 11 OUTPUT BIT 10 OUTPUT BIT 9 OUTPUT BIT 8 OUTPUT BIT 7 VSS OUTPUT BIT 6 OUTPUT BIT 5 OUTPUT BIT 4 OUTPUT BIT 3 OUTPUT BIT 2 OUTPUT BIT 1
(0, 0)
VSS
ST2225A-D
RESET
VDD BRIGHTNESS CONTROL
CLK
DATA
DATA ENABLE
Die Size: 1449.6um * 2614um Pad Size: 100um * 100um
Figure 3
* Note: SiTI reserves the right to improve the device geometry and manufacturing processes without prior notice. Though these improvements may result in slight geometry changes, they will not affect die electrical characteristics and pad layouts.
Wafer Information
Material Silicon with P-Substrate Diameter 6 inches(15cm) Thickness 12 mils(300um) Width of scribe line100um Malfunctioned dieMarked with red ink or equivalent marking
LED Display Driver -3VersionA.025
SILICON TOUCH TECHNOLOGY INC.
ST2225A
Pad Allocation for the Bare Chip, ST2225A-D
Center Coordinate (X,Y) um 666.2 2574.7 526.2 2574.7 381.2 2574.7 236.2 2574.7 91.2 100.1 100.1 100.1 100.1 100.1 100.1 100.1 100.1 100.1 100.1 100.1 100.1 100.1 100.1 168.6 385.7 520.7 2574.7 2225.2 2075.2 1925.2 1775.2 1625.2 1475.2 1325.2 1185.2 1045.2 895.2 745.2 595.2 446.6 306.6 109.7 109.7 109.7 Center Coordinate (X,Y) um 744 109.7 1033.2 109.7 1322.4 109.7 1375.9 295.2 1375.9 1375.9 1375.9 1375.9 1375.9 1375.9 1375.9 1375.9 1375.9 1375.9 1375.9 1375.9 1375.9 1375.9 1241.2 1096.1 951.2 806.2 445.2 595.2 745.2 895.2 1045.2 1185.2 1325.2 1475.2 1625.2 1775.2 1925.2 2075.2 2225.2 2574.7 2574.7 2574.7 2574.7 2574.7
PAD Name VSS OUTPUT17 OUTPUT16 OUTPUT15 OUTPUT14 OUTPUT13 OUTPUT12 OUTPUT11 OUTPUT10 OUTPUT9 OUTPUT8 OUTPUT7 VSS OUTPUT6 OUTPUT5 OUTPUT4 OUTPUT3 OUTPUT2 OUTPUT1 RESET IBRIGHT VDD
PAD Name CLK DATA DATAENZ OUTPUT35 OUTPUT34 OUTPUT33 OUTPUT32 OUTPUT31 OUTPUT30 VSS OUTPUT29 OUTPUT28 OUTPUT27 OUTPUT26 OUTPUT25 OUTPUT24 OUTPUT23 OUTPUT22 OUTPUT21 OUTPUT20 OUTPUT19 OUTPUT18
LED Display Driver
-4-
VersionA.025
SILICON TOUCH TECHNOLOGY INC.
ST2225A
Absolute Maximum Ratings
Voltage (any pin)........................Vss to Vss +12V Power Dissipation (PD) +25......................................................1.52W +85....................................................790mW Junction Temperature (Tj)........................+150 Storage Temperature (Ts)..........-65 to +150 Lead Temperature (soldering, 10 sec.).....+300
Electrical Characteristics
4.5VVDD 11V, Vss=0V; TA=25, bold values indicate -40TA+85unless noted
Symbol IDD VIL VIH IBC IOUT OFF IOUT ON VBC RMATCH fC tH tL tDS tDH tDES Condition -25 to +85, excluding output loads Power Supply Current -40 to +85, excluding output loads logic-0 level, 10A input bias Low-level Data Input Voltage logic-1 level, 4.75VVDD 5.25V High-level Data Input Voltage logic-1 level, VDD>5.25V Brightness Control Input Current Note 2 Output Sink Current When "OFF" Segment off, VOUT=3.0V Segment on, VOUT=1.0V, Note 3 Brightness input =0A Output Sink Current When "ON" Brightness input =100A Brightness input =750A Brightness Control Input Voltage Input Current =750A Note 1 Output Matching Notes 4, 5 Clock Input Frequency Notes 4, 5 Clock Input High Time Notes 4, 5 Clock Input Low Time Data Input Setup Time Data Input Hold Time Data Enable Input Setup Time Parameter Min Typ Max 5 6 0.8 VDD VDD 0.75 10 10 4 25 4.3 20 500 Units mA mA V V V mA A A mA mA V % kHz ns ns ns ns ns
-0.3 2.2 VDD-2 0
0 2.0 15 3.0
2.7 20
950 950 300 300 100
Note 1: Output matching is calculated as the percent variation (IMAX + IMIN) / 2 Note 2: With a fixed resistor on the brightness input pin, some variation in brightness will occur among devices. Note 3: VOUT should be so regulated that power dissipation of the chip will not exceed its limit. Note 4: AC input waveform specification for test purpose: tR20ns, tF20ns, t=500kHz, 50%10% duty cycle. Note 5: Clock input rise and fall times must not exceed 300ns.
LED Display Driver
-5-
VersionA.025
SILICON TOUCH TECHNOLOGY INC.
ST2225A
Operating Ratings
Supply Voltage (VDD - VSS) ..............................+4.75V to 11V Ambient Temperature Range (TA)..................-40 to +85
Functional Description
The ST2225A display driver can drive either 4- or 5-digit alphanumeric LED displays. One of its advantages is its minimal interface requirement with the display or data source. Data transfer is accomplished by sending clock and serial data signals, without any need of an external load signal. This method provides a non-multiplexed, direct drive to the LED display. The data transfer format uses a leading "1" followed by 35 data bits. These 35 data bits are latched after the 36th has been transferred. In this way, data output (refers to the currently displayed characters) changes only if the serial data bits differ from those previously transferred. Display brightness is controlled by the output current for LED displays. A 1nF capacitor should be connected to brightness control pin to prevent oscillations. Figure 1 shows the block diagram of this driver. The output current is set via an external variable resistor, and is typically 27 times greater than the current in brightness control pin. Input data format, as in Figure 4, shows a leading "1" followed by 35 data bits. When the 36th is transferred, a LOAD signal is generated synchronously with the clock high state, thus, the 35 bits of data are loaded into the latches. The low state of the clock is used to generate a RESET signal to clear all shift registers for the next set of data. To allow continuous operation, all shift registers are static master-slaves, with no clear for the master portion of the first register.
LED Display Driver
-6-
VersionA.025
SILICON TOUCH TECHNOLOGY INC.
ST2225A
Note that a complete set of 36 clocks must be sent in order to clear the shift registers. When ST2225A is powered ON, reset signal is generated internally to reset all registers and all latches. Then, the START bit and the first clock make it return to its normal operation. Figure 2 shows the pin-out of the package for ST2225A. Figure 3 shows the pad-assignment of the bare chip for ST2225A.The timing relationships between data, clock and DATA ENABLE is shown in Figure 4, with maximum clock frequency of 0.5 MHz assumed. When this driver is used for applications with lesser number of outputs, the current per output can be increased, or the part can be operated at higher than 1V (Vout). The following equation can be used for calculations. Tj = (Vout) (ILED) (NO. of segments) (82/W)+TA Where: Tj = junction temperature (150 max) Vout = the voltage at the LED driver outputs ILED = the LED current 82/W = thermal resistance of the package TA = ambient temperature The above equation was used to plot Figure 6-8.
CLOCK
DATA 300 nS MIN DATA ENABLE 100 nS MIN
Figure 4
LED Display Driver
-7-
VersionA.025
SILICON TOUCH TECHNOLOGY INC.
ST2225A
1 CLOCK START BIT 1 DATA LOAD (INTERNAL) RESET
36
37
BIT 34 BIT 35
Figure 5 Input Data Format
Output Current v.s. Number of Segments 180
3.00
Vout v.s. ILED
Ta = 85
160
Vout = 1V
140 Output Current (mA) 120 100
Ta = 85 Tj = 150 (max.)
2.50
20 SEGM Vout = 1.5V
Vout (Volt) 2.00
30 SEGM
Vout = 2V
80 60 40
1.50
1.00
35 SEGM
0.50
20 0 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 Figure 6 Number of Segments
0.00 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35
Figure 7
ILED (mA)
Power dissipation v.s. Temperature 2.0 1.8 1.6 1.4 1.2 Pdiss (W) 1.0 0.8 0.6 0.4 0.2 0.0 0 5 10 15 20 25 30 35 40 45 50 55 Figure 8 Temp('C) 60 65 70 75 80 85
35 Segments Vout = 1V 15 mA/Segment
Safe Operating Area
LED Display Driver
-8-
VersionA.025
SILICON TOUCH TECHNOLOGY INC.
ST2225A
Typical Applications
LED DISPLAY
AM
FM
35 ST2225A DISPLAY DRIVER
KEYBOARD
ELECTRONIC TUNING CONTROLLER
PLL SYNTHESIZER
STATION DETECT, ETC
Figure 9 Basic Electronically Tuned Radio System
VLED=3.0V VLED VLED
VLED=3.0V
9-12, 2-8, 48 40-47 31-35, 14-17 37-39 ST2225A 19 27 28 21 1, 13 36 29 18
CLOCK IN DATA IN BRIGHTNESS CONTROL 100K TYP
VDD
Figure 10 Duplexing 8 Digits with One ST2225A
LED Display Driver
-9-
VersionA.025
SILICON TOUCH TECHNOLOGY INC.
ST2225A
Package Outline ( SSOP48 ) for ST2225A-SS3
48
25
C
E1
E
1
24
D
GAUGE PLANE
Hx45
A
0.010 INCH
L
SYMBOL A A1 b C e E E1 H L N
DIMENSION IN MM MIN. NOM. MAX. 2.413 2.591 2.794 0.203 0.305 0.406 0.203 0.343 0.127 0.254 0.635 BASIC 10.033 10.668 7.391 7.493 7.595 0.381 0.635 0.508 1.016 0 8 D DIMENSION (IN INCH)
0.620 0.625
A1 DIMENSION IN INCH MIN. NOM. MAX. 0.095 0.102 0.110 0.008 0.012 0.016 0.008 0.0135 0.005 0.010 0.025 BASIC 0.395 0.420 0.291 0.295 0.299 0.015 0.025 0.020 0.040 0 8 JEDEC
MO-118(AA) 0.630
e
b
48
LED Display Driver
-10-
VersionA.025
SILICON TOUCH TECHNOLOGY INC.
ST2225A
The products listed herein are designed for ordinary electronic applications, such as electrical appliances, audio-visual equipment, communications devices and so on. Hence, it is advisable that the devices should not be used in medical instruments, surgical implants, aerospace machinery, nuclear power control systems, disaster/crime-prevention equipment and the like. Misusing those products may directly or indirectly endanger human life, or cause injury and property loss. Silicon Touch Technology, Inc. will not take any responsibilities regarding the misusage of the products mentioned above. Anyone who purchases any products described herein with the above-mentioned intention or with such misused applications should accept full responsibility and indemnify. Silicon Touch Technology, Inc. and its distributors and all their officers and employees shall defend jointly and severally against any and all claims and litigation and all damages, cost and expenses associated with such intention and manipulation.
LED Display Driver
-11-
VersionA.025

▲Up To Search▲

Price & Availability of ST2225A

	To Download ST2225A Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .