MDT75C277 OTP Encoder 1. General Description The MDT75C277 is an OTP Encoder using CMOS technology. It has a maximum of 20 bits addressing code providing up to one million codes. It can reduce any code collision and unauthorized code scanning possibilities. 2. Features CMOS technology. Wide range of Operating Voltage : Vdd = 3.0V ~ 12V. Up to 4 data pins. Total 1048576 address codes. Built-in RC oscillator with single external resistor. Available in DIP and SOP package. Automatically enter sleep mode if press button over 3 ~ 5 sec 3. Pin Assignment MDT75C277P / 75C277S 8 pin DIP / SOP OSCR 1 8 Vdd 2 7 Vss 3 6 TXD 4 5 K3 K2 K1 K0 4. Pin Function Description Symbol I/O OSCR I Function Description Connect a resistor to Vdd to adjust internal RC freq. Vdd Positive power supply 3.0V ~ 12 V. Vss Ground. TXD O Data output pin. K0 I Data input with pull low Resistor. K1 I Data input with pull low Resistor. K2 I Data input with pull low Resistor. K3 I Data input with pull low Resistor. 1 of 1 2006/10/11 Ver. 1.5 This specification is subject to be changed without notice. Please visit our web site for the most updated information. http://www.mdtic.com.tw MDT75C277 OTP Encoder 5.Output Data Reporting Output data frame Preamble C0 ~ C19 ( 1048576 address codes ) D0 D1 D2 D3 Preamble : 4 Ick 124 Ick for 75C277 Data High : 12 Ick 4 Ick Data Low : 4 Ick 12 Ick Note : 1 Ick = 8 OSC clocks 6. Key 0 ~ 3 combination table K3 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 K2 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 K1 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 K0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 D3 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 2 of 2 D2 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 D1 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 D0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 2006/10/11 Ver. 1.5 This specification is subject to be changed without notice. Please visit our web site for the most updated information. http://www.mdtic.com.tw MDT75C277 OTP Encoder 7. Absolute Maximum Rating Symbol Vdd Parameter Conditions Supply Voltage Rating Unit -0.3 ~ 13 V Vi Input Voltage -0.3 ~ Vdd+0.3 V Vo Output Voltage -0.3 ~ Vdd+0.3 V Tst Storage Temp. -40 ~ 125 Top Operating Temp. -20 ~ 70 Pdis Max. Power dissipation Vdd = 12V 300 mV 8. DC Electrical Characteristics (TA=0℃ to 70℃) Symbol Parameters Vdd Operating Voltage Isb Stand by current Conditions Min. Typ. Max. Unit 3.0 5 12 V 1 20 uA 0.6 1.0 mA Vdd = 12V, OSC stop K0 ~ K3 = Low Output Unloaded Iop Operating current Ioh Source current Vdd =12V, Voh = 6V 4.5 mA Iol Sink Current Vdd =12V, Vol = 6V 4.5 mA Fop Operating Freq Vdd =12V Vdd=11V, Rext=390K ~ 510K ohm 3 of 3 80K HZ 2006/10/11 Ver. 1.5 This specification is subject to be changed without notice. Please visit our web site for the most updated information. http://www.mdtic.com.tw MDT75C277 OTP Encoder 9. External oscillator resistor selection table (Vdd=11V) Rext (ohm) Freq. (Hz) Operating Current 1.2 M ( Max ) 33.9 K 476 µA 1M 36.9 K 482 µA 680 K 51.4 K 517 µA 620 K 55.0 K 520 µA 560 K 59.6 K 523 µA 510 K 64.7 K 525 µA 470 K 69.2 K 528 µA 430 K 73.2 K 532 µA 390 K 78.2 K 535 µA 360 K 82.3 K 539 µA 330 K 88.5 K 545 µA 300 K ( Min ) 96.2 K 553 µA 4 of 4 2006/10/11 Ver. 1.5 This specification is subject to be changed without notice. Please visit our web site for the most updated information. http://www.mdtic.com.tw MDT75C277 OTP Encoder F (hz) Different Rosc (F & V) 100.0K 95.0K 90.0K 85.0K 80.0K 75.0K 70.0K 65.0K 60.0K 55.0K 50.0K 560K 510K 470K 430K 6V 7V 8V 9V 10V 11V 12V 560K 77.1K 73.2K 70.3K 67.8K 65.8K 64.1K 62.9K 510K 85.1K 80.6K 77.1K 74.4K 72.1K 70.2K 69.0K 470K 88.9K 84.4K 81.0K 78.6K 76.2K 74.4K 73.2K 430K 95.8K 91.2K 87.4K 84.0K 81.6K 79.8K 78.0K Voltage Rosc = 470K 120.0K 115.0K 110.0K 105.0K 100.0K 95.0K 90.0K 85.0K 80.0K 75.0K 70.0K 65.0K 60.0K - 40℃ - 20℃ 0℃ 25℃ 50℃ 80℃ 3V 4V 5V 6V 7V 8V 9V 10V 11V 12V 5 of 5 2006/10/11 Ver. 1.5 This specification is subject to be changed without notice. Please visit our web site for the most updated information. http://www.mdtic.com.tw MDT75C277 OTP Encoder 10. Application circuit ( Reference ) Vdd ROSC 1 2 + 4.7u 3 0.1u R1 1MΩ 4 OSCR K3 VDD K2 VSS K1 TXD K0 8 SW3 7 SW2 6 SW1 5 SW0 Vss Transmitter Circuit (a). If encoder circuit has one switch only to control ON/OFF power & key data together, then circuit must add R1 resister 1MΩ . (b). To increase the stability of RC oscillator can add 100 pF capacitor at Rosc in parallel . (c). To increase the stability of K3 ~ K0 key data can increase pull low resister 100K connect key and Vss , K3 ~ K0 internal pull low resister is 450K (Vdd=9V), 6 of 6 2006/10/11 Ver. 1.5 This specification is subject to be changed without notice. Please visit our web site for the most updated information. http://www.mdtic.com.tw MDT75C277 OTP Encoder TXD 7 of 7 2006/10/11 Ver. 1.5 This specification is subject to be changed without notice. Please visit our web site for the most updated information. http://www.mdtic.com.tw