G680 ETC
Document overview
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Technical content
Features
High ±±±±2% Voltage Threshold Accuracy Independently Adjustable High- and Low- Voltage Thresholds Fully Specified Over Temperature Available in Three Output Configurations Push-Pull RESET Output (G680L) Push-Pull RESET Output (G680H) Open-Drain RESET Output (G681L) 140ms min Power-On Reset Pulse Width 4µA Supply Current Power Supply Transient Immunity 5-Pin SOT23-5 Packages
Applications
Computers Controllers Intelligent Instruments Critical µP and µC Power Monitoring Portable / Battery-Powered Equipment Automotive General Description The G680/G681 are microprocessor (µP) supervisory circuits used to monitor the power supplies in µP and digital systems. High- and Low- voltage thresholds can be adjusted independently, allowing for wide hystere- sis. Voltage detection thresholds are accurate to 2%. These circuits perform a single function: they assert a reset signal whenever the V CC supply voltage declines below the low-voltage threshold, keeping it asserted for at least 140ms after V CC has risen above the high-voltage threshold. The G681L has an open-drain output stage, while the G680 have push-pull outputs. The G681L’s open-drain RESET output requires a pull-up resistor that can be connected to a voltage higher than V CC. The G680L have an active-low RESET output, while the G680H has an active-high RESET output. The reset com- parator is designed to ignore fast transients on thresh- old input. The IC’s power supply is separate from the detector inputs, allowing the G680/G681 to be powered from a down-stream supply. Low supply current (4µA, typical) makes the G680/G681 ideal for use in portable equipment. The G680/G681 are available in 5 pin SOT 23-5 packages.
Ordering Information
PART TEMP. RANGE PIN-PACKAGE G680H(L)T1 -40°C ~ +105°C SOT23-5 G681LT1 -40°C ~ +105°C SOT23-5 P i n C o n f i g u r a t i o n T y p i c a l O p e r a t i n g C i r c u i t Vcc RESET(RESET) SOT23-5 1HTH GND LTH G680/G681 () is for G680H RESET INPUT GND µP VCC RESET (RESET) GND G680/G681 VCC RPULL-UP VCC *G681 ONLY HTH LTH Vcc RESET(RESET) SOT23-5 1HTH GND LTH G680/G681 () is for G680H Vcc RESET(RESET) SOT23-5 1HTH GND LTH G680/G681 () is for G680H RESET INPUT GND µP VCC RESET (RESET) GND G680/G681 VCC RPULL-UP VCC *G681 ONLY HTH LTH RESET INPUT GND µP VCC RESET (RESET) GND G680/G681 VCC RPULL-UP VCC *G681 ONLY HTH LTH
Ver: 03 Preliminary Jan 25 2002 TEL: 886-3-5788833 http://www.gmt.com.tw G680/G681 Global Mixed-mode Technology Inc. Absolute Maximum Ratings Terminal Voltage (with respect to GND) Continuous Power Dissipation (TA = +70°C) Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress rat- ings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational se ctions of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Electrical Characteristics
(VCC = full range, TA = -40°C to +105°C, unless otherwise noted. Typical values are at TA = +25°C, VCC = 3.3V (Note 1) PARAMETER SYMBOL CONDITION MIN TYP MAX UNITS VCC Range 2.5 5.5 V Supply Current (SOT23) ICC VCC<5.5V 4 7.5 µA Reset Threshold V TH 1.225 1.25 1.272 V Reset Threshold Tempco 70 ppm/°C VLTH to Reset Delay (Note 2) V LTH = VTH to VTH – 100mV 15 µs Reset Active Timeout Period 120 420 860 ms RESET (RESET) Output Current Low IOL VCC = 2.5V, V RESET (VRESET) = 0.5V, RESET Asserted or RESET not asserted 8 mA RESET Output Current High (push-pull G680) IOH VCC = 2.5V, V RESET (VRESET) = 2V, RESET not asserted or RESET asserted. 2 mA RESET Open-Drain Output Leakage Current (G681L) VHTH>VTH, RESET deasserted 1 µA Note 1: Production testing done at TA = +25°C; limits over temperature guaranteed by design. Note 2: RESET output is for G680L/G681L; While RESET output is for G680H. Selector Guide PART / SUFFIX OUTPUT TYPE TOP MARK G680LT1 Push-pull RESET 680A G680HT1 Push-pull RESET 680B G681LT1 Open-Drain RESET 681A
Ver: 03 Preliminary Jan 25 2002 TEL: 886-3-5788833 http://www.gmt.com.tw G680/G681 Global Mixed-mode Technology Inc. Timing Diagram Functional Diagram VBATT VRESET VRESET Propagation delays not shown for clarity. VHTH VLTH tRST tRST A VOH VOL VOH VOL VBATT VRESET VRESET Propagation delays not shown for clarity. VHTH VLTH tRST tRST A VOH VOL VOH VOL High-Voltage Detect Delay Line RQ SQ One Shot Low-Voltage Detect + 1.24V Bandgap Reference GND G680/G681 RESET RESET VDD LTH HTH High-Voltage Detect Delay Line RQ SQ One Shot Low-Voltage Detect + 1.24V Bandgap Reference GND G680/G681 RESET RESET VDD LTH HTH
Ver: 03 Preliminary Jan 25 2002 TEL: 886-3-5788833 http://www.gmt.com.tw G680/G681 Global Mixed-mode Technology Inc. Typical Operating Characteristics (VCC = full range, TA = -40°C to +105°C, unless otherwise noted. Typical values are at TA = +25°C, VCC = 5V for 463/438/400 versions, VCC= 3.3V for 308/293 versions, and VCC = 3V for 263 version.) Power -Down Reset Delay vs. Temperature - 4 0 - 2 00 2 04 06 08 0 Temperature(°C) Power-Down Reset Delay(μS) VOD=10mV VOD=VTH-VLTH VOD=100mV VOD=200mV Supply Current vs. Temperature 0.5 1.5 2.5 3.5 4.5 - 4 0 - 2 00 2 04 06 08 0 Temperature (°C) Supply Current (uA) Vcc=5V Vcc=3.3V Vcc=2.5V Normalized Reset Threshold vs. Temperature 0.986 0.988 0.99 0.992 0.994 0.996 0.998 1.002 - 4 0 - 3 0 - 2 0 - 1 00 1 02 02 73 04 05 06 07 08 09 0 Temperature (°C) Normalized Reset Threshold (V) Reset Timeout Period vs. Temperature 100 200 300 400 500 600 700 800 - 4 0 - 3 0 - 2 0 - 1 00 1 02 03 04 05 06 07 08 09 0 Temperature (°C) Reset Timeout Period (ms) VCC=5.5V VCC=3V
Ver: 03 Preliminary Jan 25 2002 TEL: 886-3-5788833 http://www.gmt.com.tw G680/G681 Global Mixed-mode Technology Inc. Pin Description PIN NAME FUNCTION
1 HTH
High-Voltage Theshold (Input): Analog input to a comparator. When the level on this pin initially rises above VTH, the delay generator cycles and the RESET remains low or RESET remains high for a minimum of 140ms.
2 GND Ground
3 LTH
Low-Voltage Threshold (Input): Analog input to a comparator. This is the voltage monitor input assigned to detect a low voltage condition. When the level on this pin falls below V TH, RESET or RESET is asserted and the condition is latched until VHTH > VTH.
4 RESET (RESET)
Reset (Output): Push-pull output. This output is asserted and latched when V LTH <VTH, indicating a low voltage condition. This state remains latched until V HTH > V TH. The polarity of this signal (active-high or low) is determined by the part number suffix. See ordering information. 5 V CC Power Supply (Input): Independent supply input for internal circuitry. Detailed Description A microprocessor’s (µP’s) reset input starts the µP in a known state. The G681L/G680L/G680H assert reset to prevent code-execution errors during power-up, power-down, or brownout conditions. They assert a reset signal whenever the threshold voltage declines below V TH, keeping it asserted for at least 140ms after threshold voltage input has risen above the reset threshold. The G681L uses an open-drain output, and the G680L/G680H have a push-pull output stage. Connect a pull-up resistor on the G681L’s RESET out- put to any supply between 0 and 5.5V. Battery voltage is monitored by a comparator via a voltage divider network. The divided voltage is com- pared to an internal reference voltage. When the volt- age at the LTH input pin drops below the internal ref- erence voltage, the output is asserted. At this point, the voltage at HTH is assumed to be below the refer- ence voltage. Figure1. Maximum Transient Duration without Causing a Reset Pulse vs. Reset Com- parator Overdrive Applications Information Negative-Going VCC Transients In addition to issuing a reset to the µP during power-up, power-down, and brownout conditions, the G681L/G680H/G680L are relatively immune to short- duration negative-going V LTH transients (glitches). Figure1. shows typical transient duration vs. reset comparator overdrive, for which the G681L/G680H/ G680L do not generate a reset pulse. The graph was generated using a negative-going pulse applied to V LTH, starting 0.1V above the actual reset threshold and ending below it by the magnitude indicated (reset comparator overdrive). The graph indicates the maxi- mum pulse width a negative-going V LTH transient can have without causing a reset pulse. As the magnitude of the transient increases (goes farther below the reset threshold), the maximum allowable pulse width de- creases. Typically, a V LTH transient that goes 100mV below the reset threshold and lasts 7µs or less will not cause a reset pulse. A 0.1µF bypass capacitor mounted as close as possible to the V LTH pin provides additional transient immunity. Programming the Thresholds The low-voltage threshold is calculated using: R1+R2+R3 VBAT (Io) = VREF R2+R3 The low-voltage threshold is calculated using: R1+R2+R3 VBAT (hi) = VREF R3 where, for both equations: V BAT (hi) = 1.245V In order to provide the additional criteria needed to solve for the resistor values, the resistors can be se- lected such that they have a given total value, that is, R1 + R2 + R3 = R TOTAL. 200 400 600 800 1000 1200 1400 1 10 100 1000 Reset Comparator Overdrive, Vth-Vcc (mV) Maximun Transient Duration ( u s) G69__308/293/263 G69__463/438/400
Ver: 03 Preliminary Jan 25 2002 TEL: 886-3-5788833 http://www.gmt.com.tw G680/G681 Global Mixed-mode Technology Inc.
Package Information
Note: 1. Package body sizes exclude mold flash protrusions or gate burrs 2. Tolerance ±0.1000 mm (4mil) unless otherwise specified 3. Coplanarity: 0.1000mm 4. Dimension L is measured in gage plane DIMENSIONS IN MILLIMETERS SYMBOLS MIN NOM MAX A 1.00 1.10 1.30 A1 0.00 ----- 0.10 A2 0.70 0.80 0.90 b 0.35 0.40 0.50 C 0.10 0.15 0.25 D 2.70 2.90 3.10 E 1.40 1.60 1.80 H 2.60 2.80 3.00 θ1 1º 5º 9º Taping Specification E e D H L C b A E e D H L C b A Feed Direction Feed Direction