Datasheet CS5171, CS5172, CS5173, CS5174 (ON Semiconductor) - 5

CS5171, CS5172, CS5173, CS5174 PACKAGE PIN DESCRIPTION Package Pin Pin # Symbol Function
6 AGND Analog ground. This pin provides a clean ground for the controller circuitry and should not be in the path of large currents. The output voltage sensing resistors should be connected to this ground pin. This pin is connected to the IC substrate. 7 PGND Power ground. This pin is the ground connection for the emitter of the power switching transistor. Connection to a good ground plane is essential. 8 VSW High current switch pin. This pin connects internally to the collector of the power switch. The open voltage across the power switch can be as high as 40 V. To minimize radiation, use a trace as short as practical. VCC Thermal Shutdown Shutdown 2.0 V V Regulator SW Delay Oscillator S PWM Latch Q Driver Switch Timer R Sync SS Frequency Shift 5:1 ×5 200 k Slope Compensation Negative 2.0 V Error Amp 63 mW NFB 250 k + Ramp PGND CS5172/4 − Summer only PWM Compar- ator −0.65 V Detector + − 0.4 V Detector FB − CS5171/3 + only Positive 1.276 V Error Amp AGND VC
Figure 2. Block Diagram www.onsemi.com 5