IMP8 1 1 , IMP81 2 POWER MANAGEMENT 4-Pin µ P Volt ag e Super visor wit h Manual R eset The IMP811/IMP812 are low-power supervisors designed to monitor voltage levels of 3.0V, 3.3V and 5.0V power supplies in low-power microprocessor (µP), microcontroller (µC) and digital systems. Each features a debounced manual reset input. The IMP811/812 are improved drop-in replacements for the Maxim MAX811/812 with extended temperature specifications to 105°C. Key Features ◆ Improved Maxim MAX811/MAX812 replacement — Specified to 105°C — New 4.0V threshold option ◆ 6µA supply current ◆ Monitor 5V, 3.3V and 3V supplies ◆ Manual reset input A reset signal is issued if the power supply voltage drops below a preset threshold and is asserted for at least 140ms after the supply has risen above the reset threshold. The IMP811 has an active-low output RESET that is guaranteed to be in the correct state for VCC down to 1.1V. The IMP812 has an active-high output RESET. The reset comparator is designed to ignore fast transients on VCC . ◆ 140ms min. reset pulse width Low power consumption makes the IMP811/IMP812 ideal for use in portable and battery-operated equipment. Available in a compact 4-pin SOT143 package, the devices use minimal board space. ◆ No external components ◆ Guaranteed over temperature ◆ Active-LOW reset valid with 1.1V supply (IMP811) ◆ Small 4-pin SOT-143 package ◆ Power-supply transient-immune design Six voltage thresholds are available to support 3V to 5V systems: Reset Threshold Suffix Voltage (V) L ◆ ◆ ◆ ◆ ◆ ◆ 4.63 M 4.38 J 4.00 T 3.08 S 2.93 R 2.63 Applications Computers and controllers Embedded controllers Battery operated systems Intelligent instruments Wireless communication systems PDAs and handheld equipment Block Diagrams VCC VCC IMP811 (IMP812) MR Manual Reset RESET (RESET) GND VCC µC or µP RESET Input GND 811/12_01.eps IMP, Inc. San Jose, CA 408-432-9100/www.impweb.com IMP8 1 1 , IMP81 2 Pin Configuration SOT143 GND 1 4 VCC 3 MR IMP811 (IMP812) (RESET) RESET 2 811/12_02.eps Ordering Information Part Number 1 Reset Threshold (V) Temperature Range IMP811 Active LOW Reset with Active LOW Manual Reset Pin-Package Package Marking2 (XX Lot Code) AMXX IMP811LEUS-T 4.63 – 40°C to +105°C 4-SOT143 IMP811MEUS-T 4.38 – 40°C to +105°C 4-SOT143 ANXX IMP811JEUS-T 4.00 – 40°C to +105°C 4-SOT143 AOXX IMP811TEUS-T 3.08 – 40°C to +105°C 4-SOT143 APXX IMP811SEUS-T 2.93 – 40°C to +105°C 4-SOT143 AQXX IMP811REUS-T 2.63 – 40°C to +105°C 4-SOT143 ARXX IMP812 Active HIGH Reset with Active LOW Manual Reset IMP812LEUS-T 4.63 – 40°C to +105°C 4-SOT143 ASXX IMP812MEUS-T 4.38 – 40°C to +105°C 4-SOT143 ATXX IMP812JEUS-T 4.00 – 40°C to +105°C 4-SOT143 AUXX IMP812TEUS-T 3.08 – 40°C to +105°C 4-SOT143 AVXX IMP812SEUS-T 2.93 – 40°C to +105°C 4-SOT143 AWXX IMP812REUS-T 2.63 – 40°C to +105°C 4-SOT143 AXXX Notes: 1. Tape and Reel packaging is indicated by the -T designation. 2. Devices may also be marked with full part number: 811L, 812M etc. XX refers to lot. Absolute Maximum Ratings Pin Terminal Voltage with Respect to Ground VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to 6.0V RESET,RE SET andM R . . . . . . . . . . . . . . . . . –0.3V to (VCC + 0.3V) Input Current at VCC andM R . . . . . . . . . . . 20mA Output Current: RESET orRE SET . . . . . . 20mA Rate of Rise at VCC . . . . . . . . . . . . . . . . . . . . 100V/µs These are stress ratings only and functional operation is not implied. Exposure to absolute maximum ratings for prolonged time periods may affect device reliability 2 Power Dissipation (TA = 70°C) . . . . . . . . . . 320mW (Derate SOT-143 4mW/°C above 70°C) Operating Temperature Range . . . . . . . . . . –40°C to 105°C Storage Temperature Range . . . . . . . . . . . . . –65°C to 160°C Lead Temperature (soldering, 10 sec) . . . . . 300°C IMP8 1 1 , IMP8 1 2 Electrical Characteristics Unless otherwise noted VCC is over the full voltage range, TA = –40°C to 105°C. Typical values at TA = 25°C, VCC = 5V for L/M/J devices, VCC = 3.3V for T/S devices and VCC = 3V for R devices. Parameter Symbol Conditions Input Voltage (VCC) Range VCC Supply Current (Unloaded) ICC Reset Threshold VTH TA = 0°C to 70°C TA = – 40°C to 105°C TA = – 40°C to 85°C TA = – 40°C to 85°C TA = 85°C to 105°C TA = 85°C to 105°C L devices M devices J devices T devices S devices R devices Reset Threshold Temp. Coefficient VCC to Reset Delay VOL MR Minimum Pulse Width MR Glitch Immunity MR to RESET Propagation Delay MR Input Threshold tMR tMD VIH VIL VIH VIL MR Pull-up Resistance Low RESET Output Voltage (IMP811) VOL High RESET Output Voltage (IMP811) VOH Low RESET Output Voltage (IMP812) VOL High RESET Output Voltage (IMP812) VOH Typ 1.1 1.2 VCC < 5.5V, L/M/J VCC < 3.6V, R/S/T VCC < 5.5V, L/M/J VCC < 3.6V, R/S/T TA = 25°C TA = – 40°C to 85°C TA = 85°C to 105°C TA = 25°C TA = – 40°C to 85°C TA = 85°C to 105°C TA = 25°C TA = – 40°C to 85°C TA = 85°C to 105°C TA = 25°C TA = – 40°C to 85°C TA = 85°C to 105°C TA = 25°C TA = – 40°C to 85°C TA = 85°C to 105°C TA = 25°C TA = – 40°C to 85°C TA = 85°C to 105°C 6 5 4.56 4.50 4.40 4.31 4.25 4.16 3.93 3.89 3.80 3.04 3.00 2.92 2.89 2.85 2.78 2.59 2.55 2.50 TCVTH Reset Active Timeout Period Notes: Min VCC = VTH to (VTH - 125mV), L/M/J devices VCC = VTH to (VTH - 125mV), R/S/T devices TA = 0°C to 70°C TA = – 40°C to 105°C Note 3 Note 2 VCC > VTH (MAX), IMP811/812L/M/J 4.63 4.38 4.00 3.08 2.93 2.63 Max Units 5.5 5.5 15 10 25 20 4.70 4.75 4.86 4.45 4.50 4.56 4.06 4.10 4.20 3.11 3.15 3.23 2.96 3.00 3.08 2.66 2.70 2.76 V 30 40 20 140 100 10 µA V ppm/°C µs 560 840 ms µs ns µs V 100 0.5 2.3 0.8 VCC > VTH (MAX), IMP811/812R/S/T 0.7VCC 10 VCC = VTH min., ISINK = 1.2mA, IMP811R/S/T VCC = VTH min., ISINK = 3.2mA, IMP811L/M/J VCC > 1.1V, ISINK = 50µA VCC > VTH max., ISOURCE = 500µA, IMP811R/S/T 0.8VCC VCC > VTH max., ISOURCE = 800µA, IMP811L/M/J VCC -1.5 VCC = VTH max., ISINK = 1.2mA, IMP812R/S/T VCC = VTH max., ISINK = 3.2mA, IMP812L/M/J 1.8V < VCC < VTH min., ISOURCE = 150µA 0.8VCC 20 0.25VCC 30 0.3 0.4 0.3 kΩ V V 0.3 0.4 V V 1. Production testing done at TA = 25°C. Over temperature specifications guaranteed by design only using six sigma design limits. 2.R ESET output is active LOW for the IMP811 and RESET output is active HIGH for the IMP812. 3. Glitches of 100ns or less typically will not generate a reset pulse. 3 IMP8 1 1 , IMP81 2 Pin Descriptions Pin Number Name 1 GND Function 2 (IMP811) RESET RESET is asserted LOW if VCC falls below the reset threshold and remains LOW for the 140ms minimum after the reset conditions are removed. In addition, RESET is active LOW as long as the manual reset is low. 2 (IMP812) RESET RESET is asserted HIGH if VCC falls below the reset threshold and remains HIGH for the 140ms minimum after the reset conditions are removed. In addition, RESET is active HIGH as long as the manual reset is low. 3 MR Manual Reset Input. A logic LOW on MR asserts RESET. RESET remains active as long as MR is LOW and for 180ms after MR returns HIGH. The active low input has an internal 20kΩ pull-up resistor. The input should be left open if not used. It can be driven by TTL or CMOS logic or shorted to ground by a switch.. 4 VCC Power supply input voltage (3.0V, 3.3V, 5.0V) Ground Related Products Max. Supply Current Package Pins Manual RESET input Package Type Active-HIGH RESET output Active-LOW RESET output 4 IMP809 IMP810 IMP811 IMP812 15µA 3 15µA 3 SOT-23 SOT-23 ■ 15µA 4 ■ SOT-143 15µA 4 ■ SOT-143 ■ ■ ■ IMP8 1 1 , IMP8 1 2 Detailed Description Reset Timing and Manual Reset (MR) The reset signal is asserted–LOW for the IMP811 and HIGH for the IMP812 – when the VCC signal falls below the threshold trip voltage and remains asserted for 140ms minimum after the VCC has risen above the threshold. MR may be connected to a normally-open switch connected to ground without an external debounce circuit. For added noise rejection, a 0.1µF capacitor from MR to Ground can be added. A logic low on MR asserts RESET LOW on the IMP811 and HIGH on the IMP812. MR is internally pulled high through a 20kΩ resistor and can be driven by TTL/CMOS gates or with open collector/drain outputs. MR can be left open if not used. 5V VTH VCC 0V Active Reset Timeout Period 140ms minimum 5V MR 0V Active Reset Timeout Period 5V RESET IMP811 0V 5V RESET IMP812 0V 811/12_03.eps Figure 1. Reset Timing and Manual Reset (MR) 5 IMP8 1 1 , IMP81 2 Application Information RESET Output Operation In µP/µC systems it is important to have the processor begin operation from a known state or be able to return the system to a known state. A RESET output to a processor is provided to prevent improper operation during power supply sequencing or low voltage – brownout – conditions. The IMP811/812 are designed to monitor the system power supply voltages and issue a RESET signal when levels are out of range. RESET outputs are guaranteed to be active for VCC above 1.1V. When VCC exceeds the reset threshold, an internal timer keeps RESET active for the reset timeout period, after which RESET becomes inactive (HIGH for the IMP811 and LOW for the IMP812). If VCC drops below the reset threshold, RESET automatically becomes active. Alternatively, external circuitry or a human operator can initiate this condition using the Manual Reset (MR) pin. There is an internal pullup on MR so it can be left open if it is not used. MR can be driven by TTL/CMOS logic or even an external switch, since it is already debounced. If the switch is at the end of a long cable, it might require a bypass (100nF) at the pin if noise pickup is a problem. Six voltage thresholds are available to support 3V and 5V systems: Reset Threshold Suffix Voltage (V) L 4.63 M 4.38 J 4.00 T 3.08 S 2.93 R 2.63 Valid Reset with VCC under 1.1V Negative VCC Transients To ensure that logic inputs connected to the IMP811 RESET pin are in a known state when VCC is under 1.1V, a 100kΩ pull-down resistor at RESET is needed. The value is not critical. Typically short duration transients of 100mV amplitude and 20µs duration do not cause a false RESET. A 0.1µF capacitor at VCC increases transient immunity. A similar pull-up resistor to VCC is needed with the IMP812. VCC VCC 100kΩ IMP811 Power Supply MR Power Supply MR RESET 100kΩ GND 811/12_04.eps Figure 2. RESET Valid with VCC Under 1.1V 6 IMP812 RESET GND 811/12_05.eps Figure 3. RESET Valid with VCC Under 1.1V IMP8 1 1 , IMP8 1 2 Bi-directional Reset Pin Interfacing The IMP811/812 can interface with µP/µC bi-directional reset pins by connecting a 4.7kΩ resistor in series with the IMP809/810 reset output and the µP/µC bi-directional reset pin. BUF Buffered RESET VCC IMP811 Power Supply µC or µP 4.7kΩ MR RESET RESET Input GND GND Bi-directional I/O Pin (Example: 68HC11) 811/12_06.eps Figure 4. Bi-directional Reset Pin Interface Package Dimensions Plastic SOT-143 (4-Pin) Inches B e1 Min E H A 0.031 0.047 0.787 1.194 A1 0.001 0.005 0.025 0.127 B 0.014 0.022 0.356 0.559 B1 0.030 0.038 0.762 0.965 C 0.0034 0.006 0.086 0.152 e D 0.105 0.120 2.667 3.048 D E 0.047 0.055 1.194 1.397 e 0.070 0.080 1.778 2.032 e1 0.071 0.079 1.803 2.007 H 0.082 0.098 2.083 2.489 I 0.004 0.012 0.102 0.305 B1 a = 0°-8° A A1 Millimeters Max Min Max Plastic SOT-143 (4-Pin) e C L SOT-143 (4-Pin).eps 7 IMP8 1 1 , IMP81 2 IMP, Inc. Corporate Headquarters 2830 N. First Street San Jose, CA 95134-2071 Tel: 408-432-9100 Tel: 800-438-3722 Fax: 408-434-0335 Fax-on-Demand: 1-800-249-1614 (USA) Fax-on-Demand: 1-303-575-6156 (International) e-mail: [email protected] http://www.impweb.com The IMP logo is a registered trademark of IMP, Inc. All other company and product names are trademarks of their respective owners. 8 © 1998 IMP, Inc. Printed in USA Preliminary Part No.: IMP811-812 Document Number: IMP811-6-6/98