OKI Semiconductor ML9298 FEDL9298-01 Issue Date: Jul. 11, 2005 12-Hour System Clock IC for 1/2 Duty Fluorescent Display Tubes GENERAL DESCRIPTION The ML9298 is a 12-hour system clock IC that drives 1/2 duty fluorescent display tubes. It has a wide range of power supply using an oscillation source of 4.194304 MHz. The ML9298 has a time adjustment function in hour, minute and 30-minute units, and the function has two adjustment modes, 1 Push 1 ADJ and 2Hz fast forward. Additionally, it has a brightness adjustment function for the fluorescent display tube, providing four levels of brightness settings. FEATURES • • • • • • 12-hour system Wide power supply range from 4 to 18V (built-in voltage regulator circuit) Designed for 1/2 duty fluorescent display tubes 4.194304MHz (crystal oscillation) Four levels of brightness settings Package: 32-pin plastic SSOP (SSOP32-P-430-1.00-K) (ML9298MB) 1/12 FEDL9298-01 OKI Semiconductor ML9298 BLOCK DIAGRAM Logic circuits VDDIN F64HZ Power-on reset circuit RESET XT Grid decoder DIM1 DIM2 Grid driver Frequency divide circuit XT GR1 GR2 HS ZA BLANK A/C 4b, 4c, 2b 2f Minute counter Segment decoder Hour counter 2c, col Segment driver MS Time adjustment 2a, 2d Second counter 2e 2g 3d, 1d 3e, 1e 3c, 1c 3g, 1g RESET 3f, 1f COLSEL 3b, 1b 3a, 1a TEST VDDOUT 3V regulator VCC High voltage circuit 2/12 FEDL9298-01 OKI Semiconductor ML9298 PIN CONFIGURATION (TOP VIEW) VCC 1 32 GR2 VDDOUT 2 31 GR1 VDDIN 3 30 2a, 2d TEST 4 29 4b, 4c, 2b DIM1 5 28 2f DIM2 6 27 2c, col BLANK 7 26 2e HS 8 25 2g MS 9 24 3d, 1d ZA 10 23 3e, 1e A/C 11 22 3c, 1c XT 12 21 3g, 1g XT 13 20 3f, 1f (NC) 14 19 3b, 1b F64HZ 15 18 3a, 1a GND 16 17 COLSEL 3/12 FEDL9298-01 OKI Semiconductor ML9298 PIN DESCRIPTION DIM1 DIM2 I I Pull-up/ Pull-down Pull-down Pull-down A/C I Pull-up ZA HS MS BLANK I I I I Pull-up Pull-up Pull-up Pull-down COLSEL I XT XT TEST F64Hz GR1 GR2 1a, 3a to 2b, 4b, 4c VCC GND I O I O Pull-up IC testing pin. Leave this pin open or fix it to a “H” level. 64Hz signal output pin for oscillation frequency adjustment. O Output pins for the 1/2 duty fluorescent display tube grids. O VDDOUT O VDDIN I Output pins for the 1/2 duty fluorescent display tube anodes. Power supply pin for high voltage. Ground pin. built-in regulator output pin for logic circuits. Connect the pin to the VDDIN pin. Power supply pin for logic circuits. Connect the pin to the VDDOUT pin. NC pin. Leave the pin open. Pin NC I/O Description Brightness switching pin. Input pin with a pull-up resistor to reset the circuits inside this LSI at a “L” level. Set the reset pulse width to 2 ms or more. Zero adjust pin. Hour digit adjustment pin. Minute digit adjustment pin. Blank input pin. Display disappears at a “L” level. This is the input pin for selecting flashing or lighting of the colon output. "L" level : Flashing, "H" level : Lighting Crystal oscillation pin to connect a crystal and capacitors Cx and Cy externally. 4/12 FEDL9298-01 OKI Semiconductor ML9298 ABSOLUTE MAXIMUM RATINGS Parameter Symbol Condition Rating Unit VCC Ta = 25°C –0.3 to 20 V VDDIN Ta = 25°C –0.3 to 6.5 V VHI Ta = 25°C –0.3 to VCC +0.3 V VLI Ta = 25°C –0.3 to VDDIN+0.3 V VHO Ta = 25°C –0.3 to VCC +0.3 V VLO Ta = 25°C –0.3 to VDDIN+0.3 V IHO Ta = 25°C –30 to 3 mA Output current (Logic) ILO Ta = 25°C –5 to 5 mA Power dissipation PD Ta ≤ 85°C 350 mW TSTG — –55 to 150 °C Power supply voltage (High voltage) Power supply voltage (Logic) Input voltage (High voltage) Input voltage (Logic) Output voltage (High voltage) Output voltage (Logic) Output current (High voltage) Storage temperature RECOMMENDED OPERATING CONDITIONS Parameter Power supply voltage (High voltage) Power supply voltage (Logic) Operating temperature Crystal frequency Symbol Condition Min. Typ. Max. Unit VCC — 4.0 12.0 18.0 V VDDIN — 2.8 3.2 3.6 V Ta — –40 25 85 °C f(X'tal) — 4.194304 MHz 5/12 FEDL9298-01 OKI Semiconductor ML9298 ELECTRICAL CHARACTERISTICS DC Characteristics Parameter Applicable pin Symbol (Vcc = 4.0 to 18.0 V, VDDIN = 2.8 to 3.6 V, Ta = −40 to 85°C) Condition Min. Typ. Max. Unit "H" input voltage *1) VIH VCC = 4 to 18 V VCC×0.8 — — V "L" input voltage *1) VIL — — VCC×0.2 V DIM1, DIM2, BLANK, COLSEL IIH1 20 65 200 µA −2 — 2 µA ZA, HS , MS , A/C, TEST IIH2 VCC = 4 to 18 V VCC = 12 V VIN = VCC VCC = 12 V VIN = 0 V VCC = 12 V VIN = VCC VCC = 12 V VIN = 0 V VCC = 12 V VIN = VCC VCC = 12 V VIN = 0 V VCC = 12 V IOH1 = −1 mA VCC = 12 V IOL1 = 0.55 mA VCC = 12 V IOH2 = −2 mA VCC = 12 V IOL2= 0.55 mA VCC = 12 V IOH3 = −15 mA VCC = 12 V IOL3 = 0.55 mA VDDIN = 3.0V IOH4 = −0.1mA −2 — 2 µA –200 –65 –20 µA –2 — 2 µA –2 — 2 µA VCC–2.0 — — V — — 2 V VCC–2.0 — — V — — 2 V VCC–2.0 — — V — — 2 V VDDIN–0.5 — — V VDDIN = 3.0V IOL4 = 0.1mA — — 0.5 V *4) — 400 600 µA Input current IIL1 IIL2 IIH3 COLSEL IIL3 VOH1 *2) VOL1 VOH2 *3) VOL2 Output voltage VOH3 GRID1, GRID2 VOL3 VOH4 F64HZ VOL4 Dynamic supply current VCC ICC * 1) Applicable to the following pins: DIM1, DIM2, BLANK, TEST, ZA, HS, MA, A/C, and COLSEL * 2) Applicable to the following SEGMENT output pins: 1a and 3a, 1b and 3b, 1c and 3c, 1d and 3d, 1e and 3e, 1f and 3f, 1g and 3g, 2g, 2e, and 2f * 3) Applicable to the following SEGMENT output pins: 2a, 2d, 2b and 4b, 4c and 2c, and col *4) f = 4.194304 MHz, Cg = Cd = 33pF, VCC = 12V, open input, and non-loaded output 6/12 FEDL9298-01 OKI Semiconductor ML9298 FUNCTIONAL DESCRIPTION Time Base Built-in 4.194304MHz crystal oscillation circuit (AMP, feedback resistor) * Keep crystal and external capacitors as close to this LSI as possible to minimize connection wiring. * The values of external components, such as crystal and capacitors, should be determined including capacitance of user's circuit boards. It is recommended to contact a crystal manufacturer. 7-Segment Display Format A B F G (7 segments) C E D Display Device Dynamic drive 4-digit fluorescent display tube (with colon) Relationship Between Anode/Grid Output and Display 3a GR2 GR1 2a 1a col 4b 4c 3f 3g 3e 3b 2f 2g 2e 3c 2b 1f 1b 1g 1c 2c 1e col digit4 3d digit3 colon 2d digit2 1d digit1 Brightness Switching Function 4-level brightness settings (frequency = 256 Hz, gap between GR1 and GR2 at 1/2 duty = 32 µs) Switch pin name DIM1 DIM2 Operating mode L L f = 256 Hz, 1/2 duty (50% display) H L f = 256 Hz, 1/4 duty (25% display) L H f = 256 Hz, 1/8 duty (12.5% display) H H f = 256 Hz, 1/16 duty (6.25% display) Display Mode 4-digit hour and minute display in 12-hour system Hour display ·················· 1 to 12 Minute display ············ 00 to 59 No time display when the most significant digit is 0 (Most Significant Digit Zero Suppress function) 7/12 FEDL9298-01 OKI Semiconductor ML9298 Time Adjustment Hour/Minute Fast-forwarding Function Hour and minute can be fast-forwarded separately. The HS (Hours Set) pin fast-forwards the hour digits, and the MS (Minutes Set) pin fast-forwards the minute digits individually at 2Hz. One push counts one hour or one minute. When continuously pushed, hour or minute is incremented at 2Hz. The HS and MS pins are held at a “H” level by a pull-up resistor in the open state, being in the no active state. These pins are placed in the active state by driving them at a “L” level externally. The fast-forwarding of the hour and minute digits can be performed simultaneously. When fast-forwarding the hour digits, the lower counter continues a regular operation, but the carry-over from the minute to the hour is not performed. When fast-forwarding the minute digits, carry over to the hour digits is not performed. Zero Adjustment Function (±30 minute reset to zero) The ZA (Zero Adjust) pin is held at a “H” level by a pull-up resistor in the open state, being in the no active state. This pin is placed in the active state by driving it at a “L” level externally so that hours, minutes and seconds can be adjusted to zeros. If the minute digits is less than 30 minutes, the minute and second digits are reset to 00’00”. Also, if the minute digits exceed 30 minutes, the minute and second digits are reset to 00’00”, and the hour digits are carried over. Moreover, the counter below seconds is reset up to 8 Hz. <Examples of Zero Adjustments> (X−1) hours 30 minutes 00 seconds X hours 00 minutes 00 seconds (X) hours 29 minutes 59 seconds (X) hours 30 minutes 00 seconds X hours 59 minutes 59 seconds (X+1) hours 29 minutes 59 seconds → X hours 00 minutes 00 seconds → (X+1) hours 00 minutes 00 seconds Blanking of Display Blanking occurs in display by driving the BLANK pin at a “L” level externally. Inputs from HS, MS, and ZA pins are disabled during blanking. F64Hz Pin This is the output pin for oscillation frequency adjustment, and constantly outputs a 64Hz signal. External Reset This device can be reset by placing the A/C pin at a “H” level. After reset, the display starts at “1: 00”. Built-in Regulator Circuit The built-in regulator circuit reduces the power supply voltage (VCC) for the high voltage to the power supply voltage for logic , which is output to the VDDOUT pin. Power is supplied to logic circuitry by connecting the VDDOUT pin to the VDDIN pin. Power-on Reset The power-on reset circuit built in this device eliminates the need for providing an external reset circuit. * Do the followings to operate the power-on reset circuit properly: - Make a slope of a rise time of VCC to a voltage equal to or larger than 8V/ms. - Connect a smoothing capacitor of 1000 pF±20% or more between the VDDOUT pin and GND. 8/12 FEDL9298-01 OKI Semiconductor ML9298 TEST pin This is the pin for testing this device. This pin should be left open or fixed at a “H” level when not used. Removal of Chatters Three MS, HS and ZA input pins are connected to the chatter removing circuits internally, and therefore chatters within 15.625 msec for each pin can be removed inside the device. Colon Flashing/Lighting Select Function Flashing or lighting of a colon can be selected by this COLSEL pin. COLSEL L H Operating mode Flashing at 1 Hz Lighting 9/12 FEDL9298-01 OKI Semiconductor ML9298 PACKAGE DIMENSIONS (Unit: mm) SSOP32-P-430-1.00-K Mirror finish 5 Package material Lead frame material Pin treatment Package weight (g) Rev. No./Last Revised Epoxy resin 42 alloy Solder plating (≥5µm) 0.60 TYP. 3/Dec. 5, 1996 Notes for Mounting the Surface Mount Type Package The surface mount type packages are very susceptible to heat in reflow mounting and humidity absorbed in storage. Therefore, before you perform reflow mounting, contact Oki’s responsible sales person for the product name, package name, pin number, package code and desired mounting conditions (reflow method, temperature and times). 10/12 FEDL9298-01 OKI Semiconductor ML9298 REVISION HISTORY Document No. Date Page Previous Current Edition Edition Description PEDL9298-01 Dec. 1, 2004 – – Preliminary edition 1 FEDL9298-01 July. 11, 2005 – – Final edition 1 11/12 FEDL9298-01 OKI Semiconductor ML9298 NOTICE 1. The information contained herein can change without notice owing to product and/or technical improvements. Before using the product, please make sure that the information being referred to is up-to-date. 2. The outline of action and examples for application circuits described herein have been chosen as an explanation for the standard action and performance of the product. When planning to use the product, please ensure that the external conditions are reflected in the actual circuit, assembly, and program designs. 3. When designing your product, please use our product below the specified maximum ratings and within the specified operating ranges including, but not limited to, operating voltage, power dissipation, and operating temperature. 4. Oki assumes no responsibility or liability whatsoever for any failure or unusual or unexpected operation resulting from misuse, neglect, improper installation, repair, alteration or accident, improper handling, or unusual physical or electrical stress including, but not limited to, exposure to parameters beyond the specified maximum ratings or operation outside the specified operating range. 5. Neither indemnity against nor license of a third party’s industrial and intellectual property right, etc. is granted by us in connection with the use of the product and/or the information and drawings contained herein. No responsibility is assumed by us for any infringement of a third party’s right which may result from the use thereof. 6. The products listed in this document are intended for use in general electronics equipment for commercial applications (e.g., office automation, communication equipment, measurement equipment, consumer electronics, etc.). These products are not, unless specifically authorized by Oki, authorized for use in any system or application that requires special or enhanced quality and reliability characteristics nor in any system or application where the failure of such system or application may result in the loss or damage of property, or death or injury to humans. Such applications include, but are not limited to, traffic and automotive equipment, safety devices, aerospace equipment, nuclear power control, medical equipment, and life-support systems. 7. Certain products in this document may need government approval before they can be exported to particular countries. The purchaser assumes the responsibility of determining the legality of export of these products and will take appropriate and necessary steps at their own expense for these. 8. No part of the contents contained herein may be reprinted or reproduced without our prior permission. Copyright 2005 Oki Electric Industry Co., Ltd. 12/12