PT7A7511-15/7521-25/7531-35 μP Supervisor Circuits ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Features Description Precision supply-voltage monitor 4.63V (PT7A7511, 7521, 7531) 4.38V (PT7A7512, 7522, 7532) 3.08V (PT7A7513, 7523, 7533) 2.93V (PT7A7514, 7524, 7534) 2.63V (PT7A7515, 7525, 7535) 200ms reset pulse width Debounced TTL/CMOS-compatible manualreset input Independent watchdog timer 1.6sec time-out (not available for PT7A7531 - 7535) Reset output signal: - Active-low only (PT7A7511 - 7515) - Active-high only (PT7A7521 - 7525) - Active-high and active-low (PT7A7531 - 7535) The PT7A751X/752X/753X family microprocessor (P) supervisory circuits are targeted to improve reliability and accuracy of power-supply circuitry in P’s systems. These devices reduce the complexity and number of components required to monitor power-supply and battery functions. The main functions are: 1. Asserting reset output during power-up, powerdown and brownout conditions for P system. 2. Detecting power failure or low-battery conditions with a 1.25V threshold detector. 3. Watchdog functions (not for PT7A753x) Applications Voltage monitor for power-fail or low battery Power-supply circuitry in P systems warning Guaranteed RESET/RESET valid at VCC=1.2V PT7A7511P-7515P PT7A7521P-7525P PT7A7521W-7525W 8-Pin PDIP/8-Pin SOIC PT7A7511W-7515W Pin Configuration 8-Pin PDIP/8-Pin SOIC PT7A7531P-7535P PT7A7531W-7535W 8-Pin PDIP/8-Pin SOIC MR 1 8 WDO MR 1 8 WDO MR 1 8 RESET V CC 2 7 RESET V CC 2 7 RESET V CC 2 7 RESET GND 3 6 WDI GND 3 6 WDI GND 3 6 NC PFI 4 5 PFO PFI 4 5 PFO PFI 4 5 PFO Top View PT7A7511W-7515W PT7A7521W-7525W 2014-03-0004 PT7A7531W-7535W PT0082-9 1 03/26/14 PT7A7511-15/7521-25/7531-35 μP Supervisor Circuits ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Pin Description Pin Type MR I VCC Power Supply Voltage. GND Ground Ground Reference for all signals. PFI I Power-Fail Voltage Monitor Input. When PFI is less than 1.25V, PFO goes low. Connect PFI to GND or Vcc when not used. PFO O Power-Fail Output: it gets low and sinks current when PFI is less than 1.25V; otherwise PFO stays high. WDI I Watchdog Input: If WDI remains high or low for 1.6sec, the internal watchdog timer runs out and WDO goes low. Floating WDI or connecting WDI to a high-impedance three-state buffer disables the watchdog feature. The internal watchdog timer clears whenever reset is asserted. WDI is three-stated, or WDI sees a rising or falling edge. RESET O WDO RESET O O Description Manual-Reset: triggers a reset pulse when pulled below 0.8V, active low. It has an internal 250µA pullup current and be driven from a TTL or CMOS logic line as well as shorted to ground with a switch. Reset Output pulses: low for 200ms when triggered, and stays low whenever Vcc is below the reset threshold. It remains low for 200ms after Vcc rises above the reset threshold or MR goes from low to high. A watchdog timeout will not trigger RESET unless WDO is connected to MR. Watchdog Output: pulls low when the internal watchdog timer finishes its 1.6sec count and does not go high again until the watchdog is cleared. WDO also goes low during low-line conditions. Whenever Vcc is below the reset threshold, WDO stays low; however, unlike RESET, WDO does not have minimum pulse width. As soon as Vcc rises above the reset threshold, WDO goes high with no delay. The inverse of RESET, active high. Whenever RESET is high, RESET is low. Block Diagram Block Diagram of PT7A7511-7515/7521-7525 WDI Watchdog Transition Detector Watchdog Timer Vcc WDO Timebase for Reset & Watchdog 250uA MR RESET Reset Generator (RESET) Vcc V RST PFI PFO 1.25V 2014-03-0004 PT0082-9 2 03/26/14 PT7A7511-15/7521-25/7531-35 μP Supervisor Circuits ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Block Diagram of PT7A7531-35 Vcc 250uA RESET MR Reset Generator RESET Vcc VRST PFI PFO 1.25V Maximum Ratings Storage Temperature ............................................................-65oC to +150oC Ambient Temperature with Power Applied.......................... -40oC to +85oC Supply Voltage to Ground Potential (Vcc to GND) ..............-0.3V to +7.0V DC Input Voltage (All inputs except Vcc and GND)......-0.3V to VCC+0.3V DC Output Current (All outputs) ..........................................................20mA Power Dissipation .......................................... 500mW (Depend on package) Note: Stresses greater than those listed under 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 above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Recommended Operation Conditions Sym VCC Description Supply Voltage for 75x1,75x2 Supply Voltage for 75x3,75x4 Supply Voltage for 75x5 Test Conditions - VIH1 MR Input High Voltage VIH2 WDI Input High Voltage VIL1 MR Input Low Voltage VIL2 WDI Input Low Voltage VCC > 4.0V VCC ≤ 4.0V VCC > 4.0V VCC ≤ 4.0V - TA Operating Temperature - 2014-03-0004 Min 4.5 3.0 2.7 2.0 0.7VCC 0.7VCC - Typ 5.0 3.3 3.0 2.4 - -40 - PT0082-9 3 Max 5.5 5.5 5.5 0.8 0.2VCC 0.3VCC 85 Unit V V V V V V V V ℃ 03/26/14 PT7A7511-15/7521-25/7531-35 μP Supervisor Circuits ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| DC Electrical Characteristics (VCC = VRN + 5% to 5.5V, TA= -40~85ºC, unless otherwise noted.)(Note 1) Symbol ICC Description Supply Current Test Conditions 75x1/x2 Vcc = 5V, 75x3/x4 Vcc = 3.3V, 75x5 Vcc = 3.0V, Left WDI unconnected (No output load) Min Typ Max Unit - 30 200 µA VIH Input High Voltage Pin: MR, WDI 0.7VCC - - V VIL Input Low Voltage Pin: MR, WDI TA= 25ºC - - 0.3VCC V VRN - 1.5% VRN VRN + 1.5% 75x1 4.560 4.630 4.699 75x2 4.314 4.380 4.446 75x3 3.034 3.080 3.126 75x4 2.886 2.930 2.974 75x5 2.590 2.630 2.669 VCC Varies between VRN - 5% - 70 - Vcc 4.5V Isource=800µA Vcc-1.5 - - Vcc 2.7V Isource=500µA 0.8×Vcc - - Vcc 1.8V Isource=150µA 0.8×Vcc - - Vcc 4.5V Isink=3.2mA - - 0.4 Vcc 2.7V Isink=1.2mA - - 0.3 Vcc 1.2V Isink=100µA VPFI varies from 1.0V to 1.5V - - 0.3 1.23 1.25 1.27 VPFI varies from 0V to 1.0V 1.20 1.25 1.30 PFI connected to Vcc - - 2.00 PFI connected to GND -2.00 - - WDI connected to VCC - 30 100 WDI connected to GND -100 -30 - VRST VRTH＋ VOH VOL Reset Threshold Voltage (Note 2) Reset Threshold Voltage (Note 2) Output High Voltage Output Low Voltage VPFT PFI Input Threshold IPFI PFI Input Current IWDI Average WDI Input Current (Note 3) V mV V V V µA µA IMR -600 -250 -100 µA MR input Current MR=0, Vcc = 5V Note: 1. Parameters of room temperature guaranteed by production test and parameters of full-temperature guaranteed by design. 2. Valid for both RESET and RESET. VRST is the Reset threshold voltage when VCC from high to low level, VRN is nominal reset threshold voltage. 3. WDI is internally serviced within the watchdog period if WDI is left unconnected. 2014-03-0004 PT0082-9 4 03/26/14 PT7A7511-15/7521-25/7531-35 μP Supervisor Circuits ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| AC Electrical Characteristics Symbol Description Test Conditions Min Typ Max Unit tRS Reset Pulse Width MR from low to High, TA=25℃ 160 200 280 ms tWD Watchdog Timeout Period WDI, MR tied to Vcc, Vcc>VRN+5% , TA=25℃ 1.2 1.6 2.25 s tMR MR Pulse Width - 200 - - ns tMD MR to RESET Delay WDI Pulse Width Vcc=5V - - 250 ns 150 - - ns tWP - Watchdog Timing Diagram tWP tWD tWD tWD 5V WDI 0V 5V WDO 0V 5V Externally Triggered by MR RESET 0V tRS 5V RESET 0V Watchdog Timing Diagram VCC VRT VRT 5V tRS tRS 0V 5V RESET 0V MR 5V 0V tMD tMR 5V WDO 0V 2014-03-0004 PT0082-9 5 03/26/14 PT7A7511-15/7521-25/7531-35 μP Supervisor Circuits ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Functional Description The PT75xx family can assert reset output during power-up, power-down and brownout conditions for P system, detect power failure or low-battery conditions with a 1.25V threshold detector and have watchdog functions. Refer to Function Table of PT7A75xx Family for their individual features. The typical application see Figure 4. Reset Output The supervisory circuits can assert reset for a microprocessor during power-up, power-down and brownout to prevent code execution errors. On power-up, once Vcc reaches about 1.2V, RESET is a guaranteed logic low of 0.4V or less. As Vcc rises, RESET stays low. When Vcc rises above the reset threshold, an internal timer releases RESET after about 200ms. RESET pulses low whenever Vcc drops below the reset threshold, i.e. brownout condition. If brownout occurs in the middle of a previously initiated reset pulse, the pulse continues for at least another 140ms. On power-down, once Vcc falls below the reset threshold, RESET stays low and is guaranteed to be 0.4V or less until Vcc drops below 1.0V. The PT7A752x and PT7A753x active-high RESET output is simply the inverse of the RESET output, and is guaranteed to be valid with Vcc down to 1.2V. Some Ps, such as Intel’s 80C51, require an active-high reset pulse. Watchdog Timer The watchdog circuit monitors the P activity. If the P does not toggle the watchdog input (WDI) within 1.6sec and WDI is not in high impedance, WDO goes low. As long as RESET is asserted or the WDI input is in high impedance, the watchdog timer will stay cleared and will not count. As soon as reset is released and WDI is driven high or low, the timer will start counting. Pulses as short as 50ns can be detected. Typically, WDO will be connected to the non-maskable interrupt input (NMI) of a P. When VCC drops below the reset threshold, WDO will go low whether or not the watchdog timer has timed out yet. Normally this would trigger an NMI interrupt, but RESET goes low simultaneously, and thus overrides the NMI interrupt. If WDI is left unconnected, WDO can be used as a low-line output. Since floating WDI disables the internal timer, WDO goes low only when V CC falls below the reset threshold, thus functioning as a low-line output. Manual Reset The manual-reset input (MR) allows reset to be triggered by a push button switch. The switch is effectively debounced by the 140ms minimum reset pulse width. MR is TTL/CMOS logic compatible, so it can be driven by any logic reset output. Power-Fail Comparator The power-fail comparator will send out a Low signal once detects a voltage lowered than 1.25V. It can be used for various purposes because its output and non-inverting input are not internally connected. The inverting input is internally connected to a 1.25V reference.. Typical Application Circuit IN DC Linear Regulator P OUT Vcc Vcc RESET P Supervisory Circuit PFI WDI WDO MR PFO 2014-03-0004 RESET I/O Line NMI Interrupt PT0082-9 6 03/26/14 PT7A7511-15/7521-25/7531-35 μP Supervisor Circuits ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Mechanical Information W (SOIC-8L) 2014-03-0004 PT0082-9 7 03/26/14 PT7A7511-15/7521-25/7531-35 μP Supervisor Circuits ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Ordering Information Note: Part Number Package Code PT7A751xWE W PT7A752xWE W PT7A753xWE W • “x” refers to voltage range, see below Function Comparison Table. • E=Lead-free or Lead-free and Green • Adding X suffix=Tape/Reel • Contact Pericom for availability. Package Lead free and Green SOIC-8L Lead free and Green SOIC-8L Lead free and Green SOIC-8L Function Comparison Table Part No. PT7A7511 PT7A7521 PT7A7531 PT7A7512 PT7A7522 PT7A7532 PT7A7513 PT7A7523 PT7A7533 PT7A7514 PT7A7524 PT7A7534 PT7A7515 PT7A7525 PT7A7535 Reset Threshold 4.63V 4.63V 4.63V 4.38V 4.38V 4.38V 3.08V 3.08V 3.08V 2.93V 2.93V 2.93V 2.63V 2.63V 2.63V Reset Active Low or High LOW HIGH LOW, HIGH LOW HIGH LOW, HIGH LOW HIGH LOW, HIGH LOW HIGH LOW, HIGH LOW HIGH LOW, HIGH Nom. Reset Time (ms), tRS 200 200 200 200 200 200 200 200 200 200 200 200 200 200 200 Nom. Watch dog Time (sec), tWD 1.6 1.6 unavailable 1.6 1.6 unavailable 1.6 1.6 unavailable 1.6 1.6 unavailable 1.6 1.6 unavailable Power Fail Comp. 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector 1.25V detector Manual Reset Input Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Pericom Semiconductor Corporation 1-800-435-2336 www.pericom.com Pericom reserves the right to make changes to its products or specifications at any time, without notice, in order to improve design or performance and to supply the best possible product. Pericom does not assume any responsibility for use of any circuitry described other than the circuitry embodied in Pericom product. The company makes no representations that circuitry described herein is free from patent infringement or other rights, of Pericom. 2014-03-0004 PT0082-9 8 03/26/14