DEMO MANUAL DC2254A LTC2956 Wake-Up Timer with Pushbutton Control Description Demonstration circuits 2254A-A and 2254A-B feature the LTC2956-1 and LTC2956-2, respectively. The LTC®2956 is a micropower, wide input voltage range, configurable wake-up timer with pushbutton control. It periodically wakes up and turns on a connected system to perform tasks like monitoring temperature or capturing images. After completing the task, the LTC2956 turns the system off to conserve power. The wake-up timer period can be adjusted from 250ms to 39 days. The DC2254A allows easy access to all the pins necessary to configure the device. Onboard jumpers, and an 8-pin DIP switch provide a range of value options, to set the wake-up timer, wake-up timer period and long power down time. Turrets are also present, allowing direct access to all the pins present on the LTC2956 to allow easy interfacing with a system with arbitrary requirements. Design files for this circuit board are available at http://www.linear.com/demo/DC2254A L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Board Photo + PSU – I/O TO SCOPE OR µP Figure 1. Test Equipment Setup dc2254af 1 DEMO MANUAL DC2254A DC2254A TURRET AND JUMPER DEFINITIONS JUMPER AND SWITCH SETTINGS RANGE TIME PERIOD (JP2): Sets the time period between enable signal assertions. The two available options present on the board are 250ms and 1s. See Applications Information in the LTC2956 data sheet and replace R11 and/or R12 if another time is desired. AWAKE TIMER (JP1): Sets the time the enable signal stays asserted. The onboard capacitor can be used for an awake time of 19.9ms or an external arbitrary capacitor can be used to set a user defined enable time. The maximum allowed awake time is set at 13.3ms/nF. LDO_IN (JP3): Choose the input to the onboard LT3060 regulator. It can either be set to INT to have it connected to the VIN pin, or EXT in order to have it driven by the LDO_IN turret. See the Operating Principles section. Only for LED/Monitor circuitry. SW1: This 8 pin DIP switch can be used to initialize the part in either RUN or SHUTDOWN mode and also allows configuration of the tLONG time. See Applications Information in the LTC2956 data sheet for more information. SW2: This pushbutton switch controls the input to the PB pin. This is an active low input with a 900kΩ pull up to an internal 3.3V regulated supply. When the pushbutton is pressed, EN/EN pin gets asserted after an initial debounce time of 32ms. EXTERNAL CONNECTIONS Signal connections are made via the row of turret posts along the edges of the board. GND: (3 Turrets) These turrets are connected directly to the ground planes. VIN: Connect a 1.6V to 36V power supply to this turret. ONMAX: Connect a capacitor from this turret to GND if an arbitrary awake time is desired. Use the relationship tAWAKETIME = 13.3ms/nF. Set the AWAKE TIMER jumper to EXTERNAL if using this turret. 2 PB: This turret is already driven by the pushbutton present on the demoboard, however if needed it can be driven by an external signal to simulate a pushbutton press. LDO_IN: Can be used to provide the LT3060 with power when the LDO_IN jumper is set to EXT. LDO_OUT: Output from the LT3060. The state of this turret can be monitored by the LED labelled “LED SUPPLY”. DIGITAL CONNECTIONS EN/EN: Active high (LTC2956-1) or active low (LTC2956-2) signal. Should go active either with a debounced pushbutton press or after a valid time period set by the RANGE TIME PERIOD jumper. ONALERT: This turret pulls low whenever the part goes from SHUTDOWN mode to RUN mode. The signal stays low while the EN/EN pin is asserted and it can be used as an input to a system to request for initial boot up routine. This turret may be left open if unused. OFFALERT: This turret pulls low for 1 second whenever the part goes from RUN mode to SHUTDOWN mode. This pin can be connected to the interrupt input (with a pullup resistor to the system supply) of a system to alert the system before shutdown. This pin may be left open if unused. SLEEP: This turret is an input and is active during RUN mode. In the Awake state, a falling edge at the SLEEP input will de-assert EN/EN and put the system into the Sleep state. If the SLEEP input goes high during the Sleep state, the LTC2956 reenters the Awake state and re-asserts EN/EN to turn a system on. Holding this turret high for more than tLONG (which is set by SW1) will force the LTC2956 into SHUTDOWN mode. See data sheet for more details. PBOUT: This turret follows the debounced PB input. This turret may be left open if unused. dc2254af DEMO MANUAL DC2254A OPERATING PRINCIPLES Connect a 1.6V to 36V power supply to VIN. If VIN is less than 5.5V then set the LDO_IN jumper to EXTERNAL and connect a 5.5V to 35V supply to the LDO_IN turret. The LTC2956 will still operate with no power applied to LDO_IN, but monitor LEDs will not function. On power up, the LTC2956 can be initialized to either of these two modes. SW1 provides 8 different options to initialize the part as shown in Table 1. Table 1. SW1 Configuration Table SW1 POSITION MODE TLONG 1 SHUTDOWN 0.128s 2 SHUTDOWN 0.512s The LTC2956 has two modes of operation: RUN mode and SHUTDOWN mode. 3 SHUTDOWN 1.024s 4 SHUTDOWN 2.048s In RUN mode, the LTC2956 cycles between the Awake state and the Sleep state with a period of tPERIOD which is set by the RANGE TIME PERIOD jumper. During the Awake state, the EN/EN pin is asserted to turn the system on, and the tONMAX timer runs. The tONMAX timer can be configured with the AWAKE TIMER jumper. The LTC2956 exits the Awake state when a falling edge is detected on the SLEEP pin or if the tONMAX timer expires. In the Sleep state the EN/EN output stays de-asserted. The LTC2956 only returns to the Awake state when the tPERIOD time is reached, pushbutton is pressed or if a logic high is detected on the SLEEP pin. The LTC2956 can be put into SHUTDOWN mode if the pushbutton is held low for longer than a user defined tLONG period. 5 RUN 0.128s 6 RUN 0.512s 7 RUN 1.024s 8 RUN 2.048s RUN AND SHUTDOWN MODE The SHUTDOWN mode is a very low power mode with the timer disabled, entered through a press of the pushbutton or a high pulse at the SLEEP input which lasts longer than tLONG. A short press on the pushbutton brings the LTC2956 back into RUN mode. ONALERT AND OFFALERT SIGNALS The ONALERT signal pulls low when the LTC2956 enters RUN mode from SHUTDOWN. This signal is useful to allow connected systems to run initialization tasks. The OFFALERT signal pulls low when the LTC2956 enters SHUTDOWN mode from RUN mode. When the PB pin is held low for a time longer than tLONG during RUN mode, the LTC2956 first pulls the OFFALERT pin low which lasts for tOFF (1s typ). Once the tOFF timer completes, the LTC2956 transitions to the SHUTDOWN mode. dc2254af 3 DEMO MANUAL DC2254A OPERATING PRINCIPLES PBOUT 250ms TIME PERIOD EN 20ms AWAKE TIME Figure 2. LTC2956-1, Awake Time Set to 20ms, Time Period Set to 250ms 4 dc2254af DEMO MANUAL DC2254A OPERATING PRINCIPLES PBOUT EN ONALERT Figure 3. LTC2956-1, Awake Time Set to 20ms, Time Period Set to 250ms, Showing Proper Turn On Sequence with ONALERT Signal dc2254af 5 DEMO MANUAL DC2254A OPERATING PRINCIPLES PBOUT EN 1 SEC OFFALERT ONALERT Figure 4. LTC2956-1, Awake Time Set to 20ms, Time Period Set to 250ms, Showing Proper Shutdown Sequence with OFFALERT Signal 6 dc2254af DEMO MANUAL DC2254A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER Required Circuit Components 1 1 C1 CAP., X7R, 1500pF, 25V, 10%, 0603 AVX, 06033C152KAT2A 2 1 C2 CAP., X7R, 0.1µF, 50V, 5%, 0603 AVX, 06035C104JAT2A 3 0 C3 CAP., 0603 OPT 4 1 C4 CAP., X7R, 2.2µF, 10V, 20%, 0603 MURATA, GRM188R71A225ME15D 5 1 C5 CAP., X5R, 1µF, 50V, 10%, 0603 NIC, NMC0603X5R105K50TRPF 6 1 C6 Cap., X7R, 0.01µF, 10V, 10%, 0603 AVX, 0603ZC103KAT2A 7 13 E1-E13 TP, TURRET, 0.064", PAD120-064 MILL-MAX, 2308-2-00-80-00-00-07-0 8 3 JP1, JP2, JP3 HD1X3-079 SAMTEC, TMM103-02-L-S 9 2 LED1, LED5 LED, GREEN ROHM, SML-010FTT86L 10 2 LED2-LED4 LED, YELLOW ROHM, SML-010YTT86M 11 1 LED3 LED, RED ROHM, SML-010VTT86L 12 2 R1, R12 Res., Chip 9.76k, 1/16W, 1%, 0402 VISHAY, CRCW04029K76FKED 13 1 R2 Res., Chip 26.1k, 1/16W, 1%, 0402 VISHAY, CRCW040226K1FKED 14 1 R3 Res., Chip 35.7k, 1/16W, 1%, 0402 VISHAY, CRCW040235K7FKED 15 1 R4 Res., Chip 47.5k, 1/16W, 1%, 0402 VISHAY, CRCW040247K5FKED 16 1 R5 Res., Chip 127k, 1/16W, 1%, 0402 VISHAY, CRCW0402127KFKED 17 1 R6 Res., Chip 210k, 1/16W, 1%, 0402 VISHAY, CRCW0402210KFKED 18 1 R7 Res., Chip 280k, 1/16W, 1%, 0402 VISHAY, CRCW0402280KFKED 19 1 R8 Res., Chip 383k, 1/16W, 1%, 0402 VISHAY, CRCW0402383KFKED 20 6 R9, R10, R13, R19, R21, R23 Res., Chip 100k, 1/16W, 1%, 0402 VISHAY, CRCW0402100KFKED 21 1 R11 Res., Chip 17.4k, 1/16W, 1%, 0402 VISHAY, CRCW040217K4FKED 22 2 R14, R15 Res., Chip 1k, 1/16W, 1%, 0402 VISHAY, CRCW04021K00FKED 23 0 R16 Res, 0402 OPT 24 3 R20, R22, R24 Res., Chip 430, 1/16W, 5%, 0402 VISHAY, CRCW0402430RJNED 25 1 R25 Res., Chip 158k, 1/16W, 1%, 0402 VISHAY, CRCW0402158KFKED 26 1 R26 Res., Chip 470, 1/16W, 5%, 0402 VISHAY, CRCW0402470RJNED 27 1 R27 Res., Chip 49.9k, 1/16W, 1%, 0402 VISHAY, CRCW040249K9FKED 28 1 SW1 SWITCH, 8 Position DIP C&K Components, BD08 29 1 SW2 SWITCH, Pushbutton PANASONIC, EVQPE105K 30 1 U2 I.C., LT3060ETS8, TS8 LINEAR TECH., LT3060ETS8 31 4 MH1-MH4 STAND-OFF, NYLON 0.25" TALL KEYSTONE, 8831(SNAP ON) dc2254af 7 DEMO MANUAL DC2254A Parts List ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER DC2254A-A Required Circuit Components 1 1 2 1 Q1 DC2254A1-GENERAL BOM MOSFET, N-CH, SOT23 FAIRCHILD SEMI., 2N7002 3 0 R17 RES., 0402 OPT 4 1 R18 RES., CHIP, 430, 1/16W 5%, 0402 VISHAY, CRCW0402430RJNED 4 1 U1 I.C., QFN12UD-3X3 LINEAR TECH., LTC2956IUD-1 DC2254A-B Required Circuit Components 1 1 2 0 DC2254A1-GENERAL BOM Q1 MOSFET, N-CH, SOT23 OPT 3 1 R17 RES., CHIP, 430, 1/16W, 5%, 0402 VISHAY, CRCW0402430RJNED 4 0 R18 RES., 0402 OPT 4 1 U1 I.C., QFN12UD-3X3 LINEAR TECH., LTC2956IUD-2 8 dc2254af Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. A B C D * E11 E10 E12 E13 E5 127k 210k 280k 383k R5 R6 R7 R8 JP3 LDO_IN 1 INT 2 3 EXT 47.5k R4 C5 1uF 5 ADJ SHDN LT3060ETS8 REF/BYP OUT IN 2 3 GND 4 GND GND 1 U2 JP2 RANGE TIME PERIOD 1 1s 2 3 250ms 0.128s SHUT DOWN 0.512s SHUT DOWN 1.024s SHUT DOWN 2.048s SHUT DOWN 0.128s RUN 0.512s RUN 1.024s RUN 2.048s RUN 1 2 3 4 5 6 7 8 ON 8 7 6 R12 9.76k R11 17.4k BD08 SW1 1 C6 0.01uF 16 15 14 13 12 11 10 9 C3 OPT C2 0.1uF R14 1k R13 100k R9 100k LTC2956 - 2 A B 5 U1 LTC2956 - 1 ASSY 2 1 SUFFIX EN EN E7, LED1 4 OPT 430 R17 OPT Q1 2N7002 OPT 430 R18 3 PB R15 1k 2 C4 2.2uF * R17 1 10 11 12 * * * LED1 L ED1 GREEN * R18 Q1 U1 LTC2956 - 3 THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. CUSTOMER NOTICE LED SUPPLY LED5 GREEN R26 470 R16 OPT PBOUT OFFALERT SLEEP R10 100k 2 SCALE = NONE SAL H. KIM T. R21 100k __ ECO 1 OFFALERT LED3 RED R22 430 E9 E8 E7 E6 E4 E3 GND LDO_OUT 2.5V, 100mA * PBOUT OFFALERT SLEEP ONALERT SAL H. E2 DATE 0 8 - 1 1 -1 4 APPROVED PBOUT LED4 YELLOW R24 430 1 DATE: N/A SIZE 1 LTC2956IUD-1 / 2 DEMO CIRCUIT 2254A Monday, August 11, 2014 IC NO. SHEET 1 1 OF 1 REV. WAKE UP TIMER WITH PUSH BUTTON CONTROL 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only R23 100k PRODUCTION DESCRIPTION REVISION HISTORY TECHNOLOGY REV TITLE: SCHEMATIC ONALERT LED2 YELLOW R20 430 2 APPROVALS R19 100k LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES. VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APP ENG. APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. SW2 EVQPE105K 1 VIN PERIOD RANGE R27 49.9k R25 158k 6 5 4 AWAKE TIMER EXTERNAL 3 2 13.3ms/nF 1 19.9ms C1 JP1 1500pF 1. ALL RESISTORS ARE IN OHMS, 0402. ALL CAPACITORS ARE IN MICROFARADS, 0603. NOTE: UNLESS OTHERWISE SPECIFIED GND LDO_IN 5V - 36V PB GND VIN 1.6V - 36V 26.1k 35.7k R3 9.76k R2 R1 EP 13 LONG E1 8 GND 2 ONMAX PB 1 ONALERT EN/EN 9 ONMAX 2 3 2 1 3 2 1 4 2 1 7 1 2 2 1 5 A B C D DEMO MANUAL DC2254A Schematic Diagram dc2254af 9 DEMO MANUAL DC2254A DEMONSTRATION BOARD IMPORTANT NOTICE Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions: This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations. If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES. The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or agency certified (FCC, UL, CE, etc.). No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance, customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind. LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive. Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and observe good laboratory practice standards. Common sense is encouraged. This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer. Mailing Address: Linear Technology 1630 McCarthy Blvd. Milpitas, CA 95035 Copyright © 2004, Linear Technology Corporation 10 Linear Technology Corporation dc2254af LT 0914 • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2014