UT01VS50L Voltage Supervisor Data Sheet January 9,

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Standard Products UT01VS50L Voltage Supervisor Data Sheet January 9, 2017 www.aeroflex.com/voltsupv The most important thing we build is trust FEATURES 4.75V to 5.5V Operating voltage range Power supply (V DD ) monitor set by the internal voltage reference at 4.65V Precision Input Voltage Monitor using an internal 1.25V voltage reference Watchdog Timer Circuit monitoring activity on WDI input - Nominal timeout 1.6s output responding to the V DD monitor and the manual reset input MR - Nominal pulse width 200ms level valid for V DD >=1.2V Operating Temperature Range -55 o C to +125 o C Low Power, Typical 400uA Operational environment: - Total dose: 300 krad(si) - SEL Immune: <110 MeV-cm 2 /mg @125 o C - SET Immune: <80 MeV-cm 2 /mg Packaging options: - 8-lead dual-in-line flatpack Standard Microelectronics Drawing (SMD) 5962-11213 - QML Q and V INTRODUCTION The UT01VS50L s function is to monitor vital supply and signal voltages in microprocessor systems. It provides for safe reset during power up, power down and brownout conditions by using an internal precision voltage reference. The UT01VS50L monitors activity at an independent watchdog input by employing an internal timer and a watchdog output that goes low if the input is not toggled within 1.6s. It provides for precision voltage threshold detection on an independent voltage input which could be used for battery or supply-low monitoring of a supply voltage other than V DD. The UT01VS50L includes an active low manual reset with an internal pull-up. APPLICATIONS Voltage Supervisor function for various systems including microprocessors, microcontrollers, DSPs and FPGAs Critical battery and power supply monitoring Replacement of older discrete solutions to improve reliability, accuracy and reduce complexity of the systems WDO MR & DIGITAL CONTROL VDD + GND - 4.65 V 1.25 V VREF WDI TIMER WDI TRANSITION DETECTOR OSC WDI PFI - + PFO Figure 1. UT01VS50L Functional Block Diagram 1

PIN DESCRIPTIONS Number Pins Type Description 1 MR Digital Input TTL/CMOS compatible Manual Reset Input with an internal pull-up. Active low. MR low forces the reset output low. Required minimum MR pulse width is 150ns. is held low for duration of the reset timer. 2 VDD Supply Power supply. Operating voltage range is 4.75V to 5.5V. V DD level is monitored internally by a dedicated comparator circuit, which employs an internal bandgap voltage reference nominally equal to 1.25V. Every time V DD falls below the threshold voltage, nominally 4.65V, and WDO outputs are forced low. (See WDO and descriptions.) (Figure 4.) 3 GND Supply ASIC Ground. This pin should be tied to ground and establishes the reference for voltage detection. 4 PFI Analog Input Threshold detector input. Voltage on this input is fed directly to an internal comparator where it is compared to the bandgap voltage reference of 1.25V. It can be used for detection of low battery or power failure of voltage supplies other than V DD. When voltage at PFI input drops below its threshold value of 1.25V, PFO output is forced low, otherwise, stays high. 5 PFO Digital Output Threshold detector output. Active low, push-pull output driver. It responds directly to PFI input. If PFI voltage is below the bandgap reference voltage, PFO is low. If PFI is above the reference voltage, PFO output is high. 6 WDI Digital Input Watchdog timer input pin. This pin is typically used to monitor microprocessor activity. It can assume three states: low, high and float. If WDI is floating or connected to a high impedance three state buffer, the watchdog timer is not active, and the corresponding watchdog output WDO is high. Watchdog timer is also not active any time is low. Providing that is not asserted, any change of state at WDI that is longer than 50ns will start the timer, or restart it, if the timer is already running (Figure 3.). If there is no activity within the timeout period, nominally 1.6sec, the timer will stop running and WDO output will go low (Figure 3). 7 Digital Output Reset output. Active low, push-pull output driver. This output responds to both: V DD monitoring circuits and the manual reset input MR. On power up, is guaranteed to be logic low for all V DD values from 1.2V up to the reset threshold, nominally 4.65V. Once this threshold is reached, an internal timer is activated. During the countdown output is kept low. It is raised high upon completion of countdown, typically after 200ms. If a brown out condition occurs during the reset timer countdown, the reset timer would be reset and another countdown would start after V DD levels were restored above the reset threshold. On power down, when V DD falls below the threshold voltage, goes low and is guaranteed to stay low until V DD drops below 1.2V. If MR is asserted low, is forced low and the reset timer is kept reset. When MR is released high, the timer is activated and is kept low until completion of the reset timeout, when it is raised high. 2

Number Pins Type Description 8 WDO Digital Output Watchdog output. Active low, push-pull output driver. This pin is usually connected to a non-maskable interrupt input of a microprocessor. On power up, WDO responds to V DD monitoring circuitry. It stays low until the reset threshold, 4.65V nominally, is reached. At that point, WDO is raised high. The internal watchdog timer is activated after is released. If there is no activity on WDI input, WDO goes low after the watchdog timer times out, which is typically after 1.6sec. Any activity on WDI will force WDO output to go high and the watchdog timer will be activated. If WDI is floating or connected to a high impedance buffer output, the timer is kept in a reset state and WDO stays high. When VDD drops below 4.65V, WDO goes low regardless of whether the watchdog timer has timed out or not. goes low simultaneously which prevents an interrupt. If WDI input is left unconnected, WDO can be used as a low line output. Since a floating WDI disables the internal watchdog timer, WDO goes low when V DD drops below 4.65V, thus, functioning as a low line output. (Figure 4.) Figure 2. UT01VS50L Pin Configuration 3

OPERATIONAL ENVIRONMENT PARAMETER LIMIT UNITS Total Ionizing Dose (TID) 300 krad(si) Single Event Latchup Immune (SEL) <110 MeV-cm 2 /mg Single Event Transient Immune (SET) <80 MeV-cm 2 /mg ABSOLUTE MAXIMUM RATINGS 1 (Referenced to GND) SYMBOL PARAMETER LIMITS UNITS V DD Voltage supply 7.2 V T J Maximum junction temperature 175 C T Storage temperature -65 to +150 C P D Power dissipation 2.5 W V in Input voltages -0.3V to (V DD +0.3V) V T iead Lead Temperature (soldering, 10 seconds) +300 C Θ JC Thermal resistance, junction-to-case 15 C/W V ESD ESD HBM 1000 V Notes: 1. Stresses outside the listed absolute maximum ratings may cause permanent damage to the device. This is a stress rating only, and functional operation of the device at these or any other conditions beyond limits indicated in the operational sections of this specification is not recommended. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. RECOMMENDED OPERATING CONDITIONS SYMBOL PARAMETER LIMITS UNITS V DD Positive supply voltage 4.75 to 5.5 V T C Case temperature range -55 to +125 C GND Negative supply voltage 0.0 V 4

ELECTRICAL CHARACTERISTICS 1,2 (V DD = 4.75V to 5.5V:-55 C < T C < +125 C) SYMBOL PARAMETER CONDITION MIN MAX UNIT Power Supply I DD V DD supply current V DD =5.5V 530 µa Digital Inputs and Outputs (MR,, WDI, WDO, PFO) V IL Digital input low V DD =4.75V 0.8 V V IH Digital input high V DD =5.5V 3.5 V VIL_MR Manual reset input low V DD =4.75V 0.8 V VIH_MR Manual reset input high V DD =5.5V 2.0 V V OL 3 Digital output low V DD =4.75V, I OL =3.2mA 0.4 V V OH 3 Digital output high V DD =4.75V, I OH =800µA V DD - 1.5 V Timing and Threshold Voltages t RST-ASSRT 4 V DD falling reset assertion V DD < 4.5V 0.2 0.8 µs t RS Reset pulse width V DD =4.75V 140 280 ms t WD Watchdog time-out period V DD =5.5V 1.0 2.25 s t WP Watchdog input pulse width V DD =4.75V, V IL = 0.4V, V IH =0.8XV DD 50 ns V RT Reset threshold voltage 4.5 4.75 V V RTHYS Reset threshold voltage hysteresis 20 mv t MR t MD Analog Input PFI 4 I PFI V PFI Manual reset (MR) input pulse width Manual reset (MR) to reset out delay Threshold detector input (PFI) current Threshold detector input (PFI) threshold voltage V DD =4.75V 150 ns V DD =4.75V 100 ns V DD =5.5V -20 20 na V DD =5.0V 1.20 1.30 V I MR Manual reset pull-up current V DD =5.5V, MR=0.0V -500-100 µa I WDI Watchdog input (WDI) current WDI pin = V DD = 5.5V WDI pin = 0V; V DD = 5.5V -35 35 µa µa t RPFI t FPFI PFI rising threshold crossing to PFO delay PFI falling threshold crossing to PFO delay 15 µs 35 µs 5

Notes: 1. For devices procured with a total ionizing dose tolerance guarantee, the post-irradiation performance at 25 o C per MIL-STD-883 Method 1019, Condition A, up to the maximum TID level procured (see ordering information). 2. Unless otherwise specified, V DD = 4.75V to 5.5V, -55 C < T C < +125 C. is the only parameter operable within 1.2V and the minimum recommended operating supply voltage. 3. V OL, V OH characteristics apply to WDO, PFO and 4. Guaranteed by design, but not tested.

t MR MR V DD GND t WP t WD t WD WDI V DD GND t WD WDO V DD GND t MD t RS V DD GND Figure 3. WDI and WDO timing waveforms. Reset externally triggered by MR. Figure 4. and WDO are driven low for V DD <4.65 volts. WDO is driven high when MR is low. 7

VDD 5V VIN_ANALOG 1 MR WDO 8 VDD up R1 2 VDD 7 3 GND WDI 6 I/O R2 4 PFI PFO 5 VTH= (R1+R2)/R2 ) * VPFI VPFI=1.25V +/- 50mV Figure 5. UT01VS50L Under Voltage Monitor and Detection Shown in Figure 5 is an application for monitoring the under voltage of a power supply connected to a microprocessor or ASIC. If the analog voltage monitored falls below the desired threshold value, the PFO output connected to the MR input will transition low causing the output to be asserted low indicating an under voltage condition. 3.3V_REG VDD_IO VDD 5V VREG 3.3V VIN VOUT UT01VS50L EN 1 MR WDO 8 VTH= (R1+R2)/R2 ) * VPFI VPFI=1.25V +/- 50mV R1 R2 2 VDD 7 3 GND WDI 6 4 PFI PFO 5 WDI OPEN VREG 2.5V VIN VOUT 2.5V_REG VDD 1 MR WDO 8 EN 5V Tolerant CMOS AND GATE VTH= (R3+R4)/R4 ) * VPFI VPFI=1.25V +/- 50mV R3 2 VDD 3 GND 7 WDI 6 R7 3.3V REG LED R6 R4 4 PFI PFO 5 UT01VS50L 2.5V REG LED Figure 6. Under Voltage Monitoring and sequencing of 3.3V and 2.5V Power Supplies Shown in Figure 6 are two Voltage Supervisors configured to monitor both the 3.3V and 2.5V power supplies of a system. The 3.3V regulated supply is monitored by the PFI pin of the top Voltage Supervisor, while the 2.5 V regulated supply is monitored by the PFI 8

VDD 5V VDD 1 MR WDO 8 up R1 2 VDD 7 3 GND WDI 6 I/O R2 4 PFI PFO 5 VTH= (R1+R2)/R2 ) * VPFI VPFI=1.25V +/- 50mV Figure 7. UT01VS50L Over Voltage Power Supply Monitoring and Reset Shown in Figure 7 is an application to monitor and detect power supply over voltage through the use of the PFI pin. When the voltage at the PFI input, (VTH) exceeds VREF, (1.2 to 1.3V) the PFO output transitions from low to high causing the MR output to transition from high to low. This asserts a indicating the voltage being monitored has exceeded the over voltage monitor limit. 9

VDD 5V VDD 1 MR WDO 8 up R1 2 VDD 7 3 GND WDI 6 I/O R2 4 PFI PFO 5 UT01VS50L UNDER VOLTAGE MONITOR 5V AND GATE VTH_UND= (R1+R2)/R2 ) * VPFI VPFI=1.25V +/- 50mV 1 MR WDO 8 R3 2 VDD 7 3 GND WDI 6 I/O R4 4 PFI PFO 5 UT01VS50L OVER VOLTAGE MONITOR VTH_OV= (R3+R4)/R4 ) * VPFI VPFI=1.25V +/- 50mV Figure 8. UT01VS50L Over Voltage Power Supply Monitoring and Reset Shown in Figure 8 is an application using two UT01VS50L Voltage Supervisors to monitor both under voltage and over voltage of a power supply. In this application the top Voltage Supervisor monitors the under-voltage of a 5V power supply while the bottom Voltage Supervisor monitors the over voltage of the same 5V power supply. The 5V supply is monitored through the PFI input of both Voltage Supervisors. Resistor values for both under voltage and over voltage monitoring can be set to accommodate a range of power supply voltages. During normal operation where VDD is within the allowed range (VDD_UND < VDD < VDD_OV), of both Voltage Supervisors will be at logic high level. The Table 1 below shows the truth table for functional, under voltage detection and over voltage detection. 10

Table 1. Under Voltage Over Voltage Truth Table VDD PFO_UND PFO_OV _UND _OV up or ASIC Mode Normal Operation HIGH LOW HIGH HIGH HIGH Normal VDD < VDD_UND LOW LOW LOW HIGH LOW Reset Asserted VDD > VDD_OV HIGH HIGH HIGH LOW LOW Reset Asserted 11

Figure 5. 8-pin Dual-In-Line Flatpack 12

ORDERING INFORMATION UT01VS50L VOLTAGE SUPERVISOR UT****** * * * * * Lead Finish: (Notes: 1) (C) = Gold Screening Level: (Notes: 2 and 3) (P) = Prototype Flow (C) = HiRel Flow (Temperature range -55 o C to +125 o C) Case Outline: (X) = 8-lead Ceramic Flat Package TID Tolerance: (-) = None Device Type (L) = Active low push-pull Generic part number: (01VS50) Notes: 1. Lead finish is "C" (Gold) only. 2. Prototype flow per Aeroflex Manufacturing Flows Document. Devices are tested at 25 C only. Radiation neither tested nor guaranteed. 3. HiRel Flow per Aeroflex Manufacturing Flows Document. Radiation neither tested nor guaranteed. 13

UT01VS50L VOLTAGE SUPERVISOR SMD 5962 * ***** ** * * * Lead Finish: (NOTE: 1) (C) = Gold Case Outline: (X) = 8-Lead Ceramic Flatpack Screening Level: (Q) = QML Class Q (V) = QML Class V Device Type: (13) = UT01VS50L (Temperature Range: -55 o C to +125 o C) Drawing Number: 11213 = 5.0V Single Channel Voltage Supervisor Total Dose: (R) = 100 krad(si) (F) = 300 krad(si) Federal Stock Class Number: No Options Notes: 1. Lead finish is C (gold) only. 14

C o b h a m S e m i c o n d u c t o r S o l u t i o n s - D a t a s h e e t D e f i n i t i o n A d v a n c e d D a t a s h e e t - P r o d u c t I n D e v e l o p m e n t P r e l i m i n a r y D a t a s h e e t - S h i p p i n g P r o t o t y p e D a t a s h e e t - S h i p p i n g Q M L & R e d u c e d H i - R e l The following United States (U.S.) Department of Commerce statement shall be applicable if these commodities, technology, or software are exported from the U.S.: These commodities, technology, or software were exported from the United States in accordance with the Export Administration Regulations. Diversion contrary to U.S. law is prohibited. Cobham Semiconductor Solutions 4350 Centennial Blvd. Colorado Springs, CO 80907 E: info-ams@cobham.com T: 800 645 8862 Aeroflex Colorado Springs Inc., DBA Cobham Semiconductor Solutions, reserves the right to make changes to any products and services described herein at any time without notice. Consult Aeroflex or an authorized sales representative to verify that the information in this data sheet is current before using this product. Aeroflex does not assume any responsibility or liability arising out of the application or use of any product or service described herein, except as expressly agreed to in writing by Aeroflex; nor does the purchase, lease, or use of a product or service from Aeroflex convey a license under any patent rights, copyrights, trademark rights, or any other of the intellectual rights of Aeroflex or of third parties. 15

DATA SHEET REVISION HISTORY REV Revision Date Description of Change 1 12-16 Cobham Datasheet format added along with edit to SMD Ordering on Device Type and Gold Finish. Author RL 16