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Technical content

Features

 Two low power high accuracy comparators  Precise Threshold: ±2%  7.5% Hysteresis to Eliminate the Output Chatter  Open-Drain Outputs  11µA Supply Current @VCC=3.7V  Power Supply Transient Immunity  Operating Temperature Range -40°C to +85°C  Available in SOT23-6  Lead-free, Rohs-compliant and Halogen-free Pin Assignment VCCOV GND CN305 3 4

6 UVIN

w w w . c o n s o n a n c e - e l e c . c o m 3 R e v 1 . 0 Figure 3 Monitor the Voltage Higher Than 6V Ordering Information： Part No. Package Shipping Operating Temperature Range CN305 SOT23-6 Tape and Reel, 3000/Reel －40℃ to 85 ℃

w w w . c o n s o n a n c e - e l e c . c o m 4 R e v 1 . 0 Block Diagram Figure 4 Block Diagram Pin Description Pin No. Symbol Description 1 OVIN Overvoltage Input. Generally OVIN pin should be tied to an external resistor divider to sense the voltage being monitored.

2 GND Negative Terminal of Power Supply(Ground)

Overvoltage Detect Output. Open-Drain outp ut. When the voltage at OVIN pin rises above the rising overvoltage threshold, becomes low; When the voltage at OVIN pin falls below the falling overvoltage threshold, becomes high. 4 VCC Positive Terminal of Power Supply. This pin is the power supply to internal circuit. Undervoltage Detect Output. Open-Drain output. When the voltage at UVIN pin falls below the falling undervoltage threshold, becomes low; When the voltage at UVIN pin rises above the rising undervoltage threshold, becomes high. Undervoltage Detect Input. Generally UVIN pin should be tied to an external resistor divider to sense the voltage being monitored.

w w w . c o n s o n a n c e - e l e c . c o m 5 R e v 1 . 0 ABSOLUTE MAXIMUM RATINGS Terminal Voltage (With respect to GND) Input/Output Current Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

Electrical Characteristics

(VCC＝3V , TA＝－40℃ to 85 ℃, Typical values are at TA＝25℃, unless otherwise noted.) Parameters Symbol Test Conditions M i n T y p M a x U n i t Operating V oltage Range V C C 1 . 9 6 V Operating Current I VCC VCC＝1.9V 5 1 0 1 5 uA VCC＝3.0V 6 1 1 1 6 VCC＝5.0V 7 1 2 1 7 OVIN Rising Threshold V OVTH+ OVIN voltage rises 1.187 1.211 1.235 V OVIN Falling Threshold V OVTH- OVIN voltage falls 1.09 1.12 1.15 UVIN Rising Threshold V RTH2 UVIN voltage rises 1.187 1.211 1.235 UVIN Falling Threshold V FTH2 UVIN voltage falls 1.09 1.12 1.15 OVIN Leakage Current I IN1 －100 0 100 nA UVIN Leakage Current I IN2 －100 0 100 nA OVIN to Delay tPD1 30mV Overdrive 15 us UVIN to Delay tPD2 30mV Overdrive 15 us and Low V oltage VOL VCC＝2V , ISINK＝1.5mA 0.3 V VCC＝3V , I SINK＝3.2mA 0 . 3 VCC＝5V , I SINK＝6mA 0 . 3 and High V oltage VOH VCC＝2V , ISOURCE=1.5mA VCC－0.4 V VCC＝3V , ISOURCE＝3mA VCC－0.4 VCC＝5V , VLBI＝1.5V ISOURCE＝5mA VCC－0.4 Startup Delay 2.5 ms Note: During power-up, VCC must exceed 1.9V for the startup delay time before the output is in the correct state.

w w w . c o n s o n a n c e - e l e c . c o m 6 R e v 1 . 0 Detailed Description The CN305 is a single adjustable window detector with separate under/overvoltage outputs. It consists of 2 comparators, a voltage reference and hysteresis control circuit, and is specially designed for monitoring single or multi lithium-ion (Li+) cells, multi-cell alkaline, NiCd, NiMH and multi-cell lead acid batteries. The CN305 comparators’ threshold accuracy is ±2%, and offers 7.5% hysteresis which eliminates the output chatter sometimes associated with battery voltage monitors, usually due to input voltage noise or battery terminal voltage recovery after load removal. The CN305 has 2 inputs that can be configured by the external resistor divider. When the voltage at OVIN rises above the rising overvoltage threshold(V OVTH+), goes low; When the voltage at OVIN falls below the falling overvoltage threshold(VOVTH-), becomes high . When the voltage at UVIN rises above the rising under voltage threshold(VUVTH+), is driven to high. When the voltage at UVIN falls below the falling under voltage threshold(VUVTH-), is driven to low. The operation of the device can be best understood by referring to figure 5. UVIN VUVTH- VUVTH+ UV OVIN OV VOVTH+ VOVTH- Figure 5 Timing waveform Applications Information Resistor Divider Selection Choosing the proper external resistors is a balance between accuracy and current consumption. There is a leakage current into OVIN(UVIN), and the current travels through the resistor divider, which introduces error. If extremely high resistor values are used, this current introduces significant error. With extremely low resistor value, this error becomes negligible, but the resistor divider draws more current from the monitored power supply. For the application circuit shown in Figure 1, and ’s trip points are shown in Figure 6:

w w w . c o n s o n a n c e - e l e c . c o m 9 R e v 1 . 0

Package Information

Consonance does not assume any responsibility for use of any circuitry described. Consonance reserves the right to change the circuitry and specifications without notice at any time.