MIC2194_05 Datasheet, PDF (2/10 Pages) Micrel Semiconductor – 400kHz SO-8 Buck Control IC

MIC2194
Ordering Information
Part Number
Standard
MIC2194BM
Lead-Free
MIC2194YM
Output Voltage
Adjustable
Micrel
Frequency Junction Temp. Range Package
400kHz
–40°C to +125°C
8-lead SOP
Pin Configuration
COMP 1
FB 2
EN/UVLO 3
CS 4
8 VIN
7 OUTP
6 GND
5 VDD
8 Lead SOIC (M)
Pin Description
Pin Number
1
2
3
4
5
6
7
8
Pin Name
COMP
FB
EN/UVLO
CS
VDD
GND
OUTP
VIN
Pin Function
Compensation (Output): Internal error amplifier output. Connect to a
capacitor or series RC network to compensate the regulator’s control loop.
Feedback (Input): The circuit regulates this pin to 1.245V.
Enable/Undervoltage Lockout (Input): A low level on this pin will power down
the device, reducing the quiescent current to under 0.5µA. This pin has two
separate thresholds, below 1.5V the output switching is disabled, and below
0.9V the device is forced into a complete micropower shutdown. The 1.5V
threshold functions as an accurate undervoltage lockout (UVLO) with
hysteresis.
The (–) input to the current limit comparator. A built-in offset of 110mV
between VIN and CSL in conjunction with the current sense resistor sets the
current limit threshold level. This is also the (–) input to the current amplifier.
3V internal linear-regulator output. VDD is also the supply voltage bus for the
chip. Bypass to GND with 1µF.
Ground.
High current drive for the synchronous N-channel MOSFET. Voltage swing
is from ground to VIN. On-resistance is typically 3Ω @ 5V_IN.
Input voltage to the circuit. Also the high side input to the current sense
amplifier supplies power to the gate drive circuit.
MIC2194
2
April 2005