AP2004
PWM Buck Controller
Anachip Corp.
www.anachip.com.tw Rev. 0.4 Apr 6, 2004
3/8
Recommended Operating Conditions
Symbol Parameter Min. Max. Unit
VCC Supply voltage 3.6 27 V
VI Amplifier input voltage 1.05 1.45 V
VO Collector output voltage Vcc-1.5 V
IFB Current into feedback terminal 45 µA
RF Feedback resistor 100 kΩ
CT Timing capacitor 100 6800 pF
FOSC Oscillator frequency 10 300 KHz
TOP Operating free-air temperature -20 85 ºC
Electrical Characteristics (TA=25ºC, VCC=6V, f=200 Khz)
Reference (REF)
Symbol Parameter Conditions Min. Typ. Max. Unit
Comp connect to FB 1.225 1.25 1.275 V
TA = -20ºC ~ 25ºC -0.1 ±1 %
VREF Output voltage change with
temperature TA = 25ºC ~ 85ºC -0.2 ±1 %
Under voltage lockout (UVLO)
Symbol Parameter Conditions Min. Typ. Max. Unit
VUT Upper threshold voltage (VCC) 2.9 V
VLW T Lower threshold voltage (VCC) 2.4 V
VHT Hysteresis (VCC)
IO(REF) = 0.1mA
TA = 25ºC 500 mV
Short-circuit protection (SCP) control
Symbol Parameter Conditions Min. Typ. Max. Unit
VIT Input threshold voltage TA = 25ºC 0.60 0.67 0.75 V
VSTB Standby voltage No pull up 100 130 160 mV
VLT Latched input voltage No pull up 50 100 mV
ISCP Input (source) current VI = 0.7V, TA = 25ºC -10 -15 -20 µA
VCT Comparator threshold voltage
(COMP) 1.5 V
Oscillator (OSC)
Symbol Parameter Conditions Min. Typ. Max. Unit
FOSC Frequency CT =270 pF 200 KHz
Standard deviation of frequency CT =270 pF 10
∆FOSC Frequency change with voltage VCC=3.6V ~ 20V 1
%