Datasheet

UCC28600
www.ti.com SLUS646J –NOVEMBER 2005– REVISED JULY 2011
ELECTRICAL CHARACTERISTICS
VDD = 15 V, 0.1-μF capacitor from VDD to GND, 3.3-nF capacitor from SS to GND charged over 3.5 V, 500-Ω resistor from
OVP to -0.1 V, FB = 4.8 V, STATUS = not connected, 1-nF capacitor from OUT to GND, CS = GND, T
A
= -40°C to 105°C,
(unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Overall
I
STARTUP
Startup current VDD = V
UVLO
-0.3 V 12 25
μA
I
STANDBY
Standby current V
FB
= 0 V 350 550
Not switching 2.5 3.5
I
DD
Operating current mA
130 kHz, QR mode 5.0 7.0
VDD clamp FB = GND, I
DD
= 10 mA 21 26 32 V
Undervoltage Lockout
VDD
(uvlo)
Startup threshold 10.3 13.0 15.3
Stop threshold 6.3 8 9.3 V
ΔVDD
(uvlo)
Hysteresis 4.0 5.0 6.0
PWM (Ramp)
(1)
D
MIN
Minimum duty cycle V
SS
= GND, V
FB
= 2 V 0%
D
MAX
Maximum duty cycle QR mode, f
S
= max, (open loop) 99%
Oscillator (OSC)
f
QR(max)
Maximum QR and DCM frequency 117 130 143
f
QR(min)
Minimum QR and FFM frequency V
FB
= 1.3 V 32 40 48 kHz
f
SS
Soft start frequency V
SS
= 2.0 V 32 40 48
dT
S
/dFB VCO gain T
S
for 1.6 V < V
FB
< 1.8 V -38 -30 -22 μs/V
Feedback (FB)
R
FB
Feedback pullup resistor 12 20 28 kΩ
V
FB
FB, no load QR mode 3.30 4.87 6.00
Green-mode ON threshold V
FB
threshold 0.3 0.5 0.7
Green-mode OFF threshold V
FB
threshold 1.2 1.4 1.6
Green-mode hysteresis V
FB
threshold 0.7 0.9 1.1 V
FB threshold burst-ON V
FB
during green mode 0.3 0.5 0.7
FB threshold burst-OFF V
FB
during green mode 0.5 0.7 0.9
Burst Hysteresis V
FB
during green mode 0.13 0.25 0.42
Status
R
DS(on)
STATUS on resistance V
STATUS
= 1 V 1.0 2.4 3.8 kΩ
I
STATUS(leakage)
STATUS leakage/off current V
FB
= 0.44 V, V
STATUS
= 15 V -0.1 2.0 μA
(1) R
SCT
and C
CST
are not connected in the circuit for maximum and minimum duty cycle tests, current sense tests and power limit tests.
Copyright © 2005–2011, Texas Instruments Incorporated 3