Microcontroller Supervisory Circuit with Push-Pull Output

MCP100/101 Microcontroller Supervisory Circuit with Push-Pull Output FEATURES • Holds microcontroller in reset until supply voltage reaches stable operating level • Resets microcontroller during power loss • Precision monitoring of 3V, 3.3V, and 5V systems • 7 voltage trip points available • Active low RESET pin (MCP100) or active high RESET (MCP101) • Push-pull output • Holds RESET/RESET for 350 ms (typical) • Guaranteed RESET/RESET to VDD = 1.0V • Accuracy of ±125mV for 5V systems and ±75mV for 3V systems over temperature • 45 µA typical operating current • Temperature range: - Industrial (I): -40°C to +85°C PACKAGES TO-92 with ‘D’ Bondout TO-92 with ‘H’ Bondout RST OR RST VDD VSS VDD RST OR VSS RST MCP100 MCP101 MCP100 MCP101 SOT-23-3 RST OR DESCRIPTION The Microchip Technology Inc. MCP100/101 is a voltage supervisory device designed to keep a microcontroller in reset until the system voltage has reached the proper level and stabilized. It also operates as protection from brown-out conditions when the supply voltage drops below a safe operating level. Both devices are available with a choice of seven different trip voltages and both have push-pull outputs. The MCP100 has a low active RESET pin and the MCP101 has a high active RESET pin. The MCP100/101 will assert the RESET/RESET signal whenever the voltage on the VDD pin is below the trip-point voltage. RST VDD MCP100 MCP101 VSS BLOCK DIAGRAM VDD Comparator + - Delay Circuit Output Driver RESET or RESET Bandgap Reference © 1999 Microchip Technology Inc. Preliminary DS11187D-page 1 MCP100/101 1.0 1.1 ELECTRICAL CHARACTERISTICS Maximum Ratings* *Notice: Stresses above 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 those or any other conditions above those indicated in the operational listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. VDD ..................................................................................7.0V All inputs and outputs w.r.t. VSS ............... -0.6V to VDD +1.0V Storage temperature .....................................-65°C to +150°C Ambient temp. with power applied ................-65°C to +125°C Soldering temperature of leads (10 seconds) ............. +300°C ESD protection on all pins .................................................. ≥ 2 kV DC AND AC CHARACTERISTICS All parameters apply at the specified temp and voltage ranges unless otherwise noted. PARAMETER Operating Voltage Range VDD Value to Guarantee RESET/ RESET Operating current MCP10X-270 MCP10X-300 MCP10X-315 MCP10X-450 MCP10X-460 MCP10X-475 MCP10X-485 MCP100-270 MCP100-300 MCP100-315 MCP100-450 MCP100-460 MCP100-475 MCP100-485 VOL VDD = 1.0 - 5.5V Industrial (I):-40°C to +85°C SYMBOL VDD VDDMIN IDD 2.55 2.85 3.0 4.25 4.35 4.50 4.60 MIN 1.0 1.0 45 2.625 2.925 3.075 4.375 4.475 4.625 4.725 60 2.7 3.0 3.15 4.50 4.60 4.75 4.85 0.4 TYP MAX 5.5 UNITS V V µA V VDD = 5.5V (no load) TEST CONDITIONS VDD Trip Point VTRIP V IOL = 3.2mA, VDD = VTRIPMIN RESET Low Level Output Voltage (MCP100) 0.6 IOL = 8.5mA, VDD = VTRIPMIN RESET High Level MCP100-XXX Output Voltage (All VTRIP Points) (MCP100) MCP101-270 MCP101-300 MCP101-315 MCP101-450 MCP101-460 MCP101-475 MCP101-485 MCP101-XXX (All VTRIP Points) VDD-0.7 VOH 0.4 V IOH = 3mA,VDD > VTRIPMAX V IOL = 3.2mA, VDD > VTRIPMAX RESET Low Level Output Voltage (MCP101) VOL 0.6 IOL = 8.5mA, VDD > VTRIPMAX RESET High level Output Voltage (MCP101) VDD-0.7 VOH VHYS tRPU tRPD 150 50 350 10 700 V IOH = 3mA,VDD = VTRIPMIN Threshold Hysteresis VDD Detect to RESET/RESET Inactive VDD Detect to RESET/RESET mV ms µs VDD ramped from VTRIPMAX + 250mV down to VTRIPMIN 250mV DS11187D-page 2 Preliminary © 1999 Microchip Technology Inc. MCP100/101 VTRIP VDD tRPU tRPD RESET (MCP100) VOH VOL RESET (MCP101) VOL FIGURE 1-1: MCP100/101 Timing Diagram 2.0 2.1 APPLICATIONS INFORMATION The Need for Supervisory Circuits 5V SUPPLY VOLTAGE VTRIPMAX VTRIPMIN (VTRIPMIN - VDD) TRANSIENT DURATION For many of today’s microcontroller applications, care must be taken to prevent low power conditions that can cause many different system problems. The most common causes are brown-out conditions where the system supply drops below the operating level momentarily, and the second, is when a slowly decaying power supply causes the microcontroller to begin executing instructions without enough voltage to sustain SRAM and producing indeterminate results. VDD MICROCONTROLLER bypass capacitor 0 0 TIME VDD 10 TA = +25°C TRANSIENT DURATION (µS) MCP100 VSS VDD RST MCLR OR RESET 8 6 Transients above the curve will cause a reset 4 VSS 2 Transients below the curve will NOT cause a reset 0 0 1 2 3 4 5 VTRIP - VDD (V) FIGURE 2-1: Typical Application 2.2 Negative Going V DD Transients FIGURE 2-2: Typical Transient Response Many system designers implementing POR circuits are concerned about the minimum pulse width required to cause a reset. Figure 2-2 shows typical transient duration vs. reset comparator overdrive for which the MCP100/101 will not generate a reset pulse. It shows that the farther below the trip point the transient pulse goes, the duration of the pulse required to cause a reset gets shorter. A 0.1 µF bypass cap mounted as close as possible to the VDD pin provides additional transient immunity. © 1999 Microchip Technology Inc. Preliminary DS11187D-page 3 MCP100/101 2.3 NORMALIZED THRESHOLD* (VTRIP) Effect of Temperature on Timeout Period (tRPU) 1.002 The timeout period (tRPU) determines how long the device remains in the reset condition. This is controlled by an internal RC timer and is effected by both VDD and temperature. The graph shown in Figure 2-3 shows typical response for different VDD values and temperatures. 1.000 0.998 0.996 0.994 700 0.992 TIMEOUT PERIOD (TRPU) (MS) 600 VDD = 6V 500 VDD = 5V 400 0.997 -40 -20 0 20 40 60 80 100 TEMPERATURE (°C) * Multiply value at 25°C by this factor to determine the value at temperature 300 VDD = 4V 200 VDD = 3V FIGURE 2-5: Normalized VTRIP vs. Temperature 800 100 -40 VDD = 2.5V -20 0 20 40 60 80 100 700 VDD = 1.5V 600 VDD = 3.5V TEMPERATURE (°C) VOL (mV) FIGURE 2-3: Typical tRPU vs. Temperature 500 400 300 VDD = 4.5V 60 VDD = 5V VDD = 5.5V 200 100 TA = +25°C 0 0 2 4 6 8 10 12 14 16 18 20 50 Operating Current (µA) 40 IOL (mA) 30 VDD = 4V 20 VDD = 3V FIGURE 2-6: VOL vs. IOL 10 1.3 0 -40 -20 0 20 40 60 80 100 1.2 TEMPERATURE (°C) 1.1 NORMALIZED IOL* FIGURE 2-4: IDD vs. Temperature 1.00 0.9 0.8 0.7 -40 -20 0 20 40 60 80 100 TEMPERATURE (°C) * Multiply value at 25°C by this factor to determine the value at temperature FIGURE 2-7: Normalized IOL vs. Temperature DS11187D-page 4 Preliminary © 1999 Microchip Technology Inc. MCP100/101 1.08 800 VDD = 2.5V 700 VDD - VOH (mV) 600 NORMALIZED VOH* 500 400 300 200 100 TA = +25°C 0 0 2 4 6 8 10 0.88 -40 -20 0 20 40 60 80 100 VDD = 5V VDD = 3.5V 1.06 1.04 1.02 1.00 0.98 0.96 0.94 0.92 0.90 VDD=3V IOH=3.2mA VDD=4.5V IOH=8.5mA TEMPERATURE (°C) * Multiply value at 25°C by this factor to determine the value at temperature IOH (mA) FIGURE 2-8: VDD - VOH vs. IOH FIGURE 2-9: Normalized VOH vs. Temperature © 1999 Microchip Technology Inc. Preliminary DS11187D-page 5 MCP100/101 NOTES: DS11187D-page 6 Preliminary © 1999 Microchip Technology Inc. MCP100/101 MCP100/101 PRODUCT IDENTIFICATION SYSTEM MCP100/101—xxx b I /pp Package: Temperature Range Bondout Option (TO-92 only) TO = TO-92 (3-lead) [offered in bags only] TT = SOT-23 (3-lead) [offered in tape & reel only] I = –40°C to +85°C (only offered in I) D = D Bond Option (see bond option chart below) H = H Bond Option 270 300 315 450 460 475 485 = = = = = = = 2.55 ≤ VTRIP ≤ 2.70 2.85 ≤ VTRIP ≤ 3.00 3.00 ≤ VTRIP ≤ 3.15 4.25 ≤ VTRIP ≤ 4.50 4.35 ≤ VTRIP ≤ 4.60 4.50 ≤ VTRIP ≤ 4.75 4.60 ≤ VTRIP ≤ 4.85 RESET/RESET VTRIP Voltage Device: MCP100 = Supervisor circuit with active low RESET output MCP100T = Supervisor circuit with active low RESET output (tape & reel) MCP101 = Supervisor circuit with active high RESET output MCP101T = Supervisor circuit with active high RESET output (tape & reel) Product Identification Options for MCP100/101 TO-92 with TO-92 with SOT-23-3 ‘D’ Bondout ‘H’ Bondout RST RST RST V VSS DD MCP100-xxxD I/TO MCP101-xxxD I/TO OR OR VDD RST VSS RST MCP100-xxxH I/TO MCP101-xxxH I/TO OR RST VDD VSS MCP100-xxx I/TT MCP101-xxx I/TT Example of Product Identification: For the MCP100 (active low RESET pin) with VTRIP range of 2.55V 2.70V in T0-92 package with ‘H’ bond option in industrial temp range, the part number would be: MCP100-270H I/TO. Sales and Support Data Sheets Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following: 1. 2. 3. Your local Microchip sales office The Microchip Corporate Literature Center U.S. FAX: (480) 786-7277. The Microchip Worldwide Site (www.microchip.com) Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using. New Customer Notification System Register on our web site (www.microchip.com/cn) to receive the most current information on our products. © 1999 Microchip Technology Inc. Preliminary DS11187D-page 7 WORLDWIDE SALES AND SERVICE AMERICAS Corporate Office Microchip Technology Inc. 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 602-786-7200 Fax: 602-786-7277 Technical Support: 602-786-7627 Web Address: http://www.microchip.com AMERICAS (continued) Toronto Microchip Technology Inc. 5925 Airport Road, Suite 200 Mississauga, Ontario