CN312

CN312 is a low-power voltage detector IC with adjustable hysteresis. The chip integrates a voltage comparator, bandgap reference, delay circuit, and hysteresis control circuit. During the tRESET period (minimum 25ms) after power-up, the LBO pin outputs high and the pin outputs low. If the monitored voltage falls below the CN312 falling threshold, after a brief delay (typical 13us), the output goes low and LBO goes high. If the monitored voltage exceeds the CN312 rising threshold for longer than the delay tD (minimum 25ms), the output goes high and LBO goes low. The difference between the rising threshold and falling threshold is the hysteresis of the CN312 comparator, which eliminates detection output glitches caused by noise on the monitored supply or battery voltage instability due to sudden load transients. Since the rising and falling thresholds of CN312 can be set independently, a relatively large hysteresis is achievable. CN312 is especially suited for monitoring single-cell or multi-cell Li-ion batteries, multi-cell alkaline batteries, NiCd batteries, NiMH batteries, and multi-cell lead-acid battery voltages.

Applications

• Battery-powered systems
• Single-cell or multi-cell lithium battery monitoring
• Multi-cell alkaline, NiCd, and NiMH battery monitoring
• Multi-cell lead-acid battery monitoring

Key features

• Threshold detection accuracy: ±1%
• Hysteresis eliminates detection output chattering
• Hysteresis adjustable via external resistor
• Power-on valid output delay: 35ms (typical)
• CMOS output
• Available in active-low and active-high detection outputs
• Operating current 2.7μA at VCC = 3V
• Filtering of short-duration power supply transients
• Operating temperature range: -40°C to +85°C
• 6-pin SOT23 package
• Lead-free, RoHS compliant, halogen-free
• Upgraded version of CN302