EERINT oe MM5456, MIM5457 National Semiconductor Digital Clocks | J MM5456, MM5457 Digital Alarm Clocks General Description The MM5456, 57 digital alarm clock radio chips are monolithi MOS integrated circuits utilizing N-chan- nel, low threshold, enhancement mode and ion-im- planted depletion mode devices. Each circuit contains all the logic necessary for a digital clock with sleep and alarm control and is intended for clock-radio applications. Real time and alarm time are displayed in hours-minutes and sleep time is displayed in minutes, when setting the sleep counter. An alarm output is provided that beeps a 50% duty cycle, 700 Hz signal gated at 2 Hz rate: when the alarm set time and the real time matches. A sleep output that provides a DC level is used to control the radio. (t is activated with the alarm output or programmed via the sleep counter to turn OFF from 0 to 59 minutes after the sleep counter is set. The MM5456, MM5457 are bonded in a 22-pin package. The MM5457 has a 24-hour/50 Hz option and the MMS456 has the 12-hour/50 Hz or 12-hour/60 Hz options. Features Duplex LED display drive Fast/slow set capability 24-hour alarm Snooze function (9 minutes) On-chip alarm oscillator Alarm tone output gated at a 2 Hz rate Power fail indicationentire display flashes at a 1 Hz rate Automatic power-on reset PM display indicator Presettable 59 minute sleep timer A snooze feature is provided for a 9-minute recurrence Applications of the alarm after it has sounded. = Alarm clocks , . = Desk clocks Setting is done via the standard fast and slow set buttons - @ Clock radios when in the time set, alarm set or sleep set modes. = Aut bile clock These control inputs are TRI-STATE inputs to reduce utomobtle clocks pin count. | Stopwatches / @ Industrial clocks The 50/60 Hz clock selects what segment data is on Portable clocks the outputs, i.e., a duplex LED display interface. = Timers Block Diagram sono v yv +50 0R REAL TIME > +60 COUNTER ~ | . me SEGMENT OUTPUTS SLEEP COUNTER wep oceene M5456; 12 OUTPUTS + COMPARATOR MM5457: 13 OUTPUTS SNOOZE LOGIC q 4 ALARMCOUNTER Li q y. TIME SET/RUN/ +0 Voo ALARM SET FAST SET/RUN/ CONTROL SLOW SET f J +O Vs RC ALARMOFF/ SLEEP ALARM ALARMON/ = OUT TONE OUT SLEEP SET 5-70Absolute Maximum Ratings (Exceeding the following ratings may result in pernianent damage to the device) Vgg to Vgg +12V -26C to +70C ~65C to +150C 300C Voltage at Any Pin Operating Temperature Storage Temperature Lead Temperature (Soldering, 10 seconds) Electrical Characteristics power supply voltage should not exceed a maximum of 12V under any circumstances. Ta within operating range, VDD = 7V to 11V PARAMETER CONDITIONS MIN Tye MAX UNITS Power Supply Voltage Output Driving Display 9 11 Vv Functional Count Operating 7 11 Vv Power Supply Current No Output Loads Vpop =7V 4 mA Vop = 11V 5 mA 50/60 Hz Input Frequency oc _ 50/60 10k Hz Logical 0, Low Level Vss Vss Vgs+0.5 Vv Logical '1, High Level 0.7 VpD Vpb Vpp Vv Input Leakage VIN = Vpb or Vss 10 pA All Other input Voltages Logicat 0, Low Level Vss Vss Vggt0.5 Vv Logical 1'', High Level Vop71 VoD VoD Vv Power Failure Detect Voltage (Vpp Voltage) 1 5 Alarm Output, Sleep Output Vpo = 11V Sourcing, Logical 1 High VOH = VoD 1V 1 uA Sinking, Logical 0 Low VoL=Vsst 6V 5 mA Alarm Output Frequency R = 68k, C = 0.1uF 700 Hz Segment Outputs (Except Vop = 10V HTADEG) Output Sink, Logical 0 Low Vo. = Vss+2V 20 mA Leakage, Logical 1'' High VOH = VDD 10 uA Segment Output (HTADEG) Vpp = 10V Output Sink, Logical '0 Low VoL = Vsst+2V 40 mA Leakage, Logical 1 High VOH = VoD 10 uA Functional Description 50 or 60 Hz input:A shaping circuit is provided inter- nally to- square the 50 or 60 Hz input. This circuit allows use of a half sinewave input. A resistor in series must be used to limit current into the MOS device. 24-Hour/50 Hz, 12-Hour/60 Hz, 12-Hour/50 Hz (MM5456): When this input is connected to Vpp,. the display will be 12 hours with 50 Hz input. If left floating, the display will be 12 hours with 60 Hz input. (The MM5457 is internally bonded to select the 24-hour/50 Hz mode. The MM5456 selects the 12-hour/50 Hz or the 12-hour/60 Hz modes.) Steep Set/Alarm Enable/Alarm OFF: Whenever this input is connected to Vss, the sleep counters will display and be set to 59 minutes, if previously at 00 minutes. Fast set or slow set may be used to preset time other than 59 minutes. When the alarm sounds, the snooze can be activated by momentarily con- necting fast set pin .to Vpp. This will turn off the alarm for 9-10 minutes, after which the alarm will again be sounded. The snooze alarm feature may be repeatedly used for up to 59 minutes or until alarm OFF is activated by momentarily connecting this pin to Vpp. When alarm OFF is activated, the alarm latch will reset and silence the alarm. The alarm will auto- matically sound again in 24 hours (or at a new alarm setting). If it is desired to silence the alarm for a day or more, the alarm OFF input should remain at Vpp. The alarm can be enabled again by allowing the input to float. , External RC: The resistor and capacitor on this pin set the frequency of the alarm tone. The frequency is 5-71 ISYSWI 8, MM5457 - Functional Description (continued) nominally set to 1400 Hz in order to produce a 700 Hz (50% duty cycle) tone at the alarm output. Time Set/Run/Alarm Set: This input must be activated in order to set the time counter and alarm counter. When connected to Vpp, the time counter will be displayed and may be set with the fast-slow input. Upon release of fast and slow set, the time counter will be in a hotd mode. If time set/alarm set is left floating, the time counter will be displayed, and the fast-slow input will be disabled (normal run mode). When this input is con- nected to Vsg, the alarm counter will be displayed and may be set with the fast-slow input. Fast Set/Run/Slow Set: Whenever this input is con- nected to Vpp and time set or alarm set is activated, the appropriate counter will advance at a 60 Hz rate. If connected to Vgg,the minutes counter will advance at 2 Hz with carry into the hours counter. If left floating, the clock will keep normat time. When connected to Vbp and sleep set is activated, the sleep counter wil! count downward at a 10 Hz rate. If connected to Vss, the sleep counter will count downward at the slower rate; 2 Hz. Alarm Output: This output remains at Vpp when inac- tive. When the alarm latch becomes set, the alarm Typical Application 700 Hz tone will be gated by a 20% duty. cycle 2 Hz signal (i.e., the alarm tone will be ON for 100.ms and OFF for 400 ms). This output contains an internal pull-up to Vpp in order to turn OFF the external PNP transistor driver when the alarm is inactive. Sleep Output: This output. remains at Vpp when inactive. When the alarm latch becomes set or the sleep counter is at other than O00 minutes, the sleep output will be ON. Snooze or alarm OFF function will dis- able this output simultaneously with alarm output if activated by alarm latch. Snooze function will disable this output at any time if activated by sleep counter being set. This output contains an internal pull-up to Vpp in order to turn OFF the external PNP trans- istor switch when the output is inactive. Segment Outputs: All segment outputs are open- drain devices with all sources common to Vgs. Power ON and Power Failure: After power ON or power fail, the display will flash at 1 Hz rate and time, alarm, and seconds counters will be reset to 0:00:00 (12:00:00). The alarm output will be held OFF also. The power fail can be reset by enabling time set allow. QUPLEX DISPLAY / JE Ey feo J EZ [i | [3 |s E E E |s Jo [u jz = 50/60. Hz an SLEEP INPUT sucer our 47s f~__ oRive v Vs 20 he WA ms EXT AC M5456 ak | ALARM 1 4k 7 TONE GUT ie 7 eve : 7 - WA Yop te . AA oe ol time | 4 ALARM steep | 17 ALARM Fast | 13 SLOW 4k seT SET SET OFF SET SET snooze Vop + oF bE A tlf--o ree > a 100uF T 25VDC 5-72Connection Diagrams | (buat-in-Line Packages, Top Views) 12-Hour/50 or 60 Hz Clock HUB, HUG 41 22 - HTB, PM HUC, HUD 4 2 21/ HTC, HUE HUA, HUF =43 20 - SLEEP OUT Vsg] 4 19 b~ 12/60, 12/50 MTF, MTA45 18 f= 50/60 Hz INPUT MTB, MTG46 MMS456 17 p= ALARM OFF/ALARM ON/ MTD, MTC 47 16} EXT. RC MTE, MUE =] 8 15}= Yop MUB, MUG 4 9 14}- TIME SET/RUN/ALARM SET MuUc, MUD 4 10 13 Jo FAST SET (SNOOZE)/ RUN /SLOW SET MUA, MUF 11 12 b= ALARM TONE OUT Order Number MM5456N See Package 22 24-Hour/50 Hz Clock HUB, HUG41 22 HTB, PM HUC, HUD 42 21; HTADEG HUA, HUF =i 3 20 Fo HTC, HUE Vss] 4 19 == SLEEP OUT. MTF, MTA45 18 - 50 Hz INPUT MTB, MTG16 MMS4S7_ 17; ALARM OFF/ALARM ON/ MTD, MTC == 7 16 EXT. RC MTE, MUE === 15F Yoo MUB, MUG 19 14} TIME SET/RUN/ALARM SET MUC, MUD 10 13 J FAST SET (SNOOZE)/RUN/SLOW SET MUA, MUF ] 11 12 } ALARM TONE OUT Order Number MM5457N See Package 22 } 5-73