DC1562A-I

DEMO CIRCUIT 1562A QUICKLTC699X START GUIDE LTC699X-X TimerBlox: Oscillators, One Shots, PWM, and Delay DESCRIPTION Demonstration circuit 1562A is an engineering tool to design and evaluate the LTC699X-X family of TimerBlox circuits. The center section of the board contains a pre-configured TimerBlox function. DC1562A comes in twelve timing function variations as outlined in Table 1. Surrounding the center board is a ”playground” prototyping area. The prototyping area has pads for Dip-8, S8, MS8, or S6 packages with bread boarding connections to each pin and two convenient power buses and ground bus surrounding the entire area. This area is for conditioning signals to control the timer function and for adding loads controlled in time. The center part of the board can be broken away on its own as a convenience for adding a timing function to a pre-existing circuit. For application flexibility a provision is made for buffering and inverting the output of the timer. An optional NC7W04P6X SC70 package dual inverter can be added at U2 to provide this functionality. Design files for this circuit board are available. Call the LTC factory. L, LTC, LTM, LT, Burst Mode, OPTI-LOOP, Over-The-Top and PolyPhase are registered trademarks of Linear Technology Corporation. Adaptive Power, C-Load, DirectSense, Easy Drive, FilterCAD, Hot Swap, LinearView, µModule, Micropower SwitcherCAD, Multimode Dimming, No Latency ∆Σ, No Latency Delta-Sigma, No RSENSE, Operational Filter, PanelProtect, PowerPath, PowerSOT, SmartStart, SoftSpan, Stage Shedding, SwitcherCAD, ThinSOT, UltraFast and VLDO are trademarks of Linear Technology Corporation. Other product names may be trademarks of the companies that manufacture the products. USING THE DEMO BOARD To understand the simplicity and flexibility of the TimerBlox function download the appropriate datasheet from the LTC Website, www.linear.com for the device to be used. To change the board from the supplied default configuration is a simple matter of determining a few new resistor values. Simply select a pair of resistor values for the DIV value from the data sheet DIV Table, calculate the value of RSET required, replace the resistor on the board, apply power, and go! Single supply power between 2.25V and 5.5V and ground must be supplied directly to the center board. The outer prototyping section of the board can be used with Single or Dual supplies as required. When using the prototyping area, the outermost trace, which is ground, must be connected (hand wired) to the ground on the center board section. All input and output holes are sized for 65 mil. turret terminals, or wires can be soldered in the holes directly. To experiment with different timer configurations requires changing resistor values on the center board. The through hole resistor lead holes can take pressed in IC socket pins from DIP sockets or resistors can soldered directly in the holes. Pads for 0805 surface mount resistors are also included at each position where a leaded resistor could be used. Pads are also included for three 25-turn trim 1 LTC699X pots which can be used to replace RSET (R8) for master oscillator frequency adjustment, PSF in (R10) for voltage controlled options, and RDEV (R7) for frequency divider control to permit real-time adjustments while running. A TimerBlox part, decoupling cap and a bulk decoupling 10µF Tantalum cap are already placed on the board. Resistors are also provided to configure each device for a representative function to start evaluating these unique timing functions. TABLE 1. STANDARD CONFIGURATION FOR EACH VERSION Demo Board Number DC1562A-A DC1562A-B DC1562A-C DC1562A-D DC1562A-E DC1562A-F DC1562A-G DC1562A-H DC1562A-I DC1562A-J DC1562A-K DC1562A-L * ** 2 LTC Part Number LTC6990 LTC6991 LTC6992-1 LTC6992-2 LTC6992-3 LTC6992-4 LTC6993-1 LTC6993-2 LTC6993-3 LTC6993-4 LTC6994-1 LTC6994-2 Part Marking LTDWW LTDWY LTDXB LTDXD LTFCQ LTFCS LTDXG LTDXJ LTFMH LTFMK LTFCV LTFCX Rising Edge Triggered Falling Edge Triggered Function Configured Function HF OSC LF OSC PWM PWM PWM PWM One-Shot One-Shot One-Shot One-Shot Delay Delay 1KHz to 10 KHz Voltage Controlled Oscillator 1 Hz ( 1Sec ) Fixed Frequency Oscillator 10KHz 0 – 100% Duty Cycle PWM 10KHz 5 – 95% Duty Cycle PWM 10KHz 0 – 95% Duty Cycle PWM 10KHz 5 – 100% Duty Cycle PWM RET* 100 ms Positive Output Pulse RET* Re-Triggerable 100 ms Positive Output Pulse FET** Positive 100 ms Output Pulse FET** Re-Triggerable 100 ms Positive Output Pulse Output Falling Edge Delayed 100 ms from Input Falling Edge Output Rise/Fall Edges Delayed 100 ms from Input Rise/Fall Edges LTC699X DC1562A-X EXTERNAL CONNECTION DIAGRAM 3 LTC699X DC1562A-X CENTER BOARD CONNECTION DIAGRAM 4 LTC699X DEFAULT CIRCUIT CONFIGURATIONS FOR EACH VERSION DC1652A-A, 1KHZ TO 10KHZ VCO DC1652A-B, 1HZ (1SEC PERIOD) FIXED FREQUENCY OSCILLATOR DC1652A-C, 10KHZ 0% TO 100% DUTY CYCLE PWM 5 LTC699X DEFAULT CIRCUIT CONFIGURATIONS FOR EACH VERSION DC1652A-D, 10KHZ 5% TO 95% DUTY CYCLE PWM DC1652A-E, 10KHZ 0% TO 95% DUTY CYCLE PWM DC1652A-F, 10KHZ 5% TO 100% DUTY CYCLE PWM 6 LTC699X DEFAULT CIRCUIT CONFIGURATIONS FOR EACH VERSION DC1652A-G, RISING EDGE TRIGGERED 100MS POSITIVE OUTPUT PULSE ONE SHOT DC1562A-H, RISING EDGE RE-TRIGGERABLE 100MS POSITIVE OUTPUT PULSE ONE SHOT DC1562A-I, FALLING EDGE TRIGGERED 100MS POSITIVE OUTPUT PULSE ONE SHOT 7 LTC699X DEFAULT CIRCUIT CONFIGURATIONS FOR EACH VERSION DC1562A-J, FALLING EDGE RE-TRIGGERABLE 100MS POSITIVE OUTPUT PULSE ONE SHOT DC1562A-K, 100MS DELAYED OUTPUT FALLING EDGE FROM INPUT FALLING EDGE DC1562A-L, 100MS DELAYED OUTPUT EDGE FROM INPUT EDGE, BOTH RISING AND FALLING EDGES 8 LTC699X 9