SGP100 Datasheet, PDF (1/14 Pages) Fairchild Semiconductor – Primary-side-control PWM Controller

Primary-side-control PWM Controller
Product Specification
SGP100
FEATURES
„ Constant-voltage (CV) and constant-current (CC)
control without secondary-feedback circuitry
„ Green-mode function: PWM frequency linearly
decreasing
„ Fixed PWM frequency at 42kHz with frequency
hopping to solve EMI problems
„ Low start-up current: 10μA (typical)
„ Low operating current: 6.5mA (typical)
„ Peak-current-mode control in CV mode
„ Cycle-by-cycle current limiting
„ V_DD over-voltage protection with latch (OVP)
„ V_DD under-voltage lockout (UVLO)
„ Gate output maximum voltage clamped at 18V
„ Fixed over-temperature protection with latch
APPLICATIONS
„ Battery chargers for cellular phones, cordless phones,
PDA, digital cameras, and power tools
„ Replacement for linear transformer and RCC SMPS
applications. The result is a low-cost, smaller and lighter
charger than a conventional design or a linear transformer.
To minimize the standby power consumption, the
proprietary green-mode function provides off-time
modulation to linearly decrease PWM frequency under
light-load conditions. This green-mode function allows
the power supply to meet power conservation
requirements. The start-up current is only 10µA, which
allows large start-up resistance for further power saving.
A charger can be implemented with few external
components and minimal cost. A typical output CV/CC
characteristic envelope is shown in Figure 1.
Vo(V)
+/- 10%
DESCRIPTION
This highly integrated PWM controller provides several
features to enhance the performance of low-power
flyback converters. The patented topology of SGP100
enables simplified circuit design for battery charger
+/- 10%
Io(mA)
Figure 1. Typical Output V-I Characteristic
TYPICAL APPLICATION
© System General Corp.
Version 1.1.1 (IAO33.0042.B1)
-1-
www.sg.com.tw • www.fairchildsemi.com
September 26, 2007