Kingbor Technology Co.,Ltd
TEL:(86)0755-83095458 FAX:(86)0755-88364052
KB809
Microprocessor Reset circuits
Features
• Under-voltage monitor
• Power-on reset generation (180ms Typ)
• Choice of threshold voltages (contact Kingbor regarding
availability)
• Active-low reset output
• No external components required
• Rejects brief input transients
• Industry standard package and pinout
• 3-pin SOT23-3 package
General Description
The KB809 is a power supply supervisor that provides
under-voltage monitoring and power-on reset generation in
an industry standard 3-pin SOT package and pinout. The
reset output is asserted at power-on and any time the input
voltage drops below the programmed threshold. It remains
asserted for 180ms (typ.) after the input subsequently rises
back above the threshold boundary. The KB809 has an
active-low reset output. Hysteresis is included to prevent
chattering due to noise, and the KB809 is inherently
immune to brief power supply transients. Typical supply
current is a low 3µA. For those applications that require a
manual reset function, see the KB811/812. For those appli-
cations that require a longer reset timeout, see the
KB809. (The KB809 is identical to the industry-
standard KB809 with the exception of a shorter reset timout.)
Applications
• Monitoring processor, ASIC, or FPGA core and I/O
voltages
• PDAs, hand-held PCs
• Embedded controllers
• Telecommunications systems
• Power supplies
• Wireless / Cellular systems
• Networking hardware
Ordering Information
Part Number
KB809-293
Part Number
KB809-263
Marking**
ADAA C956
Marking**
AFAA C756
Typical
Application
Voltage*
3.3V
±5%
Typical
Application
Voltage*
3.3V
±10%
Nominal
Threshold
Voltage
2.93
Nominal
Threshold
Voltage
2.63
T
RST
(ms)
180
T
RST
(ms)
180
Junction
Temperature
Range
–40°C to +85°C
Junction
Temperature
Range
–40
°C
to +85°C
Package
SOT23-3
Package
SOT23-3
Top Marking:
ADAA & AFAA: To manufacture marking after 2007-3-15
C956 & C756: Before 2007-3-15
Typical Application
V
CC
VCC
KB809
Block Diagrams
VCC
µP
/RESET
/RESET
Typical Operating Circuit
March 2007
1
KB809
KINGBOR [ KINGBOR TECHNOLOGY CO ]
