TRAC® SUPPORT CIRCUIT TRAC-S2 ISSUE 1 - JANUARY 2000 DEVICE DESCRIPTION The TRAC family of Field Programmable Analog Devices offers an integrated path from signal processing problems to working silicon solutions - in minutes! The Totally Reconfigurable Analog Circuit is a highly flexible single chip solution to the signal processing problems found in many markets. FEATURES & BENEFITS Introducing a Top-Down, Structured design discipline, TRAC enables rapid implementation, prototyping and product release. Rather than working at the component level, TRAC champions the Computational Approach, providing designers with benefits formerly associated only with programmable digital devices. TRAC brings a truly integrated Signal Processing problem solving process, offering a path to Custom Silicon for higher volume users. TRAC devices have to be loaded with program data at power-up and run from a split 5V supply. By integrating the loading interface circuitry, voltage regulation, supply monitoring and thermal protection, the TRAC support circuit (TRAC-S2) further simplifies circuit integration and interface with memory devices. An adjustable frequency oscillator clocks program data out of a serial output memory device and into any number of cascaded TRAC devices. By monitoring the bit stream pattern, TRAC-S2 can sense when loading is complete and stop clocking automatically. Makes designing TRAC circuits easier, production prototyping quicker Reduces component manufacturing costs count and Enables simple connection of a serial output EEPROM or other memory device to TRAC Compatible with current and future TRAC devices Automatic program loading at power-up Supply monitor function reloads program after power failure or fluctuation Frequency of on-chip oscillator user-defined Senses number of cascaded TRAC devices automatically Automatically stops clocking when program loading complete Simplifies generation of TRAC supply voltages Ground voltage user defined Thermal shutdown function protects against overloading due to circuit failures Full industrial temperature range ORDERING INFORMATION An adjustable ‘rail-splitter’ generates the ground supply rail, and the supply monitoring function initiates program load on power-up, and after power failure or serious fluctuation. Thermal shutdown further protects the device against overheating. 1 PART NUMBER PACKAGE PART MARK TRAC-S2Q16 QSOP16 TRAC-S2 TRAC-S2 ABSOLUTE MAXIMUM RATINGS Supply Voltage Supply Current Operating Temperature Range Storage Temperature Range 0V to +7V 50mA -40°C to 85°C -55°C to 125°C ELECTRICAL CHARACTERISTICS Test Conditions: Temperature=25°C, VDD=5V, VSS=0V, CLCR_IN=0V, 100nF between AGND_OUT and VSS, unless otherwise stated. PARAMETER CONDITIONS Supply Voltage Operating Range Supply Current Standby (CLCR_IN = 0V) Clocking (CLCR_IN = 5V) MIN TYPICAL 4.8V 5.0V MAX 5.2V 1.5mA 2.9mA 1.9mA 3.7mA 2.8mA 5.5mA 50nA 200nA 2.50V 2.00V 2.51V 2.01V RAIL SPLITTER SETV(Input Current) SETV = 2.50V AGND_OUT (Output Voltage) SETV = 2.50V (No Load) SETV = 2.0V (No Load) AGND_OUT (Output Voltage) SETV = 2.50V; ISINK = 20mA SETV = 2.50V; ISOURCE= 20mA 2.49V 1.99V AGND_OUT + 0.010V AGND_OUT - 0.010V SUPPLY MONITOR RESET_OUT (Threshold Voltage) High State Output (VDD increasing) 4.35V Low State Output (VDD decreasing) 4.35V RESET_OUT (Hysteresis) 0.01V 4.67V 4.65V 4.75V 4.75V 0.02V 0.08V RESET_OUT (Onstate output sink current) VDD = RESET_OUT = 4V 0.14mA RESET_OUT (Offstate output current) VDD = RESET_OUT = 5V 0.18mA PROPAGATION DELAY VDD step from 5.0V to 4.0V 1S PROGRAMMING LOGIC CLK_OUT (Frequency) 2.2nF between CAP and VSS CLCR_IN = 5V 7kHz 10kHz 15kHz 200kHz CLK_OUT 47pF between CAP and VSS (Max Programming Frequency) CLCR_IN = 5V CLK_OUT (High output voltage) 2.2nF between CAP and VSS CLCR_IN = 5V 3.90V 4.10V 4.50V NOT CLK_OUT(Frequency) 2.2nF between CAP and VSS CLCR_IN = 5V 7kHz 10kHz 15kHz NOT CLK_OUT(High output voltage) 2.2nF between CAP and VSS CLCR_IN = 5V 4.00V 4.20V 4.60V 2 TRAC-S2 ELECTRICAL CHARACTERISTICS Test Conditions: Temperature=25°C, VDD=5V, VSS=0V, CLCR_IN=0V, 100nF between AGND_OUT and VSS, unless otherwise stated. DATA_OUT(Frequency) 2.2nF between CAP and VSS CLCR_IN = 5V 1.7kHz 2.5kHz 4.0kHz DATA_OUT(High output voltage) 2.2nF between CAP and VSS CLCR_IN = 5V 3.90V 4.10V 4.50V SELECT (Output Voltage) 2.2nF between CAP and VSS CLCR_IN = 5V 4.8V 4.99V 5.00V DESCRIPTION OF PIN FUNCTIONS Inputs SETV CLCR_IN CAP Defines the AGND_OUT voltage. Normally set by potential divider Active high to enable clock Capacitor to VSS sets clock frequency Outputs AGND_OUT SELECT CLK_OUT NOT CLK_OUT DATA_OUT RESET_OUT Analog Ground. Able to source and sink current Active high when CLCR_IN is logic high. Enables memory device Fed to EEPROM clock input Fed to TRAC clock input CLK_OUT divided by four. Fed to serial output memory device Reset for TRAC Support Circuit and TRAC devices General notes for the TRAC Support Circuit An on-chip oscillator produces the output CLK_OUT and NOT CLK_OUT. CLCR_IN must be logic high (VDD) to activate CLK_OUT and NOT CLK_OUT The CLK_OUT output frequency is divided by four to give the DATA_OUT output. Therefore CLCR_IN must be logic high (VDD) to activate DATA_OUT For AGND_OUT stability under load, a 100nF capacitor is required between AGND_OUT and VSS 3 TRAC-S2 4 TRAC-S2 5 TRAC-S2 BLOCK DIAGRAM Description of the TRAC Support Circuit 1) Rail Splitter This section provides the analog ground rail between the 5V supply. An external potential divider can be connected to the SETV pin which enables AGND_OUT to be set to the desired potential. The output stage of the rail splitter has been designed to provide power capabilities for 4 TRAC devices and accompanying circuitry. The circuit has low output resistance enabling a drive capability of +/20mA. 2) Supply Monitor This section utilises the precision ZSM560 supply monitor design. The RESET_OUT provides a signal to reset all the devices included in the programming and operation of TRAC . This ensures that all devices are switched on and off simultaneously. 3) Programming Logic This section provides TRAC and memory with the signals required for programming. The clock is generated on chip, with the frequency set by an external capacitor. The DATA_OUT signal is generated by dividing the clock frequency by 4. This provides the code to initialise an EEPROM and prompt it to output data. The SELECT pin enables EEPROM chip select. This section also takes an input signal from the final TRAC device, CLCR_IN. This signal is normally ‘high’ and goes ‘low’ when programming is complete, and is used to terminate the CLK_OUT and DATA_OUT signals. 6 TRAC-S2 APPLICATION CIRCUIT Connections between the support circuit, the EEPROM and the TRAC device are shown above. For a more detailed explanation of the circuit see the application note AN27, “How to use the TRAC support chip”. This also shows the circuit required to program multiple TRAC devices. LIST OF COMPATIBLE MEMORY DEVICES ST9346CB1 (SGS-Thomson) 93LC46B (Microchip) NM92C46 (National Semiconductor) 7 TRAC-S2 PACKAGE DIMENSIONS A IDENTIFICATION RECESS FOR PIN 1 C E J B D F PIN No.1 G K QSOP16 PIN Millimetres Inches MIN MAX MIN MAX A 4.80 4.98 0.189 0.196 B 0.635 C 0.177 0.267 0.007 0.011 D 0.20 0.30 0.008 0.012 E 3.81 3.99 0.15 0.157 F 1.35 1.75 0.053 0.069 G 0.10 0.25 0.004 0.01 J 5.79 6.20 0.228 0.244 K 0° 8° 0° 8° 0.025 NOM Zetex plc. Fields New Road, Chadderton, Oldham, OL9-8NP, United Kingdom. Telephone: (44)161 622 4422 (Sales), (44)161 622 4444 (General Enquiries) Fax: (44)161 622 4420 Zetex GmbH Streitfeldstraße 19 D-81673 München Germany Telefon: (49) 89 45 49 49 0 Fax: (49) 89 45 49 49 49 Zetex Inc. 47 Mall Drive, Unit 4 Commack NY 11725 USA Telephone: (631) 543-7100 Fax: (631) 864-7630 Zetex (Asia) Ltd. 3510 Metroplaza, Tower 2 Hing Fong Road, Kwai Fong, Hong Kong Telephone:(852) 26100 611 Fax: (852) 24250 494 These are supported by agents and distributors in major countries world-wide Zetex plc 2000 Internet:http://www.zetex.com This publication is issued to provide outline information only which (unless agreed by the Company in writing) may not be used, applied or reproduced for any purpose or form part of any order or contract or be regarded as a representation relating to the products or services concerned. The Company reserves the right to alter without notice the specification, design, price or conditions of supply of any product or service. 8