TS432IRF TSC [Taiwan Semiconductor Company, Ltd], TS432IRF Datasheet - Page 3

• Manufacturer Part Number: TS432IRF
• Description: Adjustable Precision Shunt Regulator
• Manufacturer: TSC [Taiwan Semiconductor Company, Ltd]

Test Circuits
Additional Information – Stability
When The TS432I/432AI/432BI is used as a shunt regulator, there are two options for selection of C
stability:
A) No load capacitance across the device, decouple at the load.
B) Large capacitance across the device, optional decoupling at the load.
The reason for this is that TS432I/432AI/432BI exhibits instability with capacitances in the range of 10nF to 1uF (approx.) at light
cathode current up to 3mA (typ). The device is less stable the lower the cathode voltage has been set for. Therefore while the
device will be perfectly stable operating at a cathode current of 10mA (approx.) with a 0.1uF capacitor across it, it will oscillate
transiently during start up as the cathode current passes through the instability region. Select a very low capacitance, or alternatively
a high capacitance (10uF) will avoid this issue altogether. Since the user will probably wish to have local decoupling at the load
anyway, the most cost effective method is to use no capacitance at all directly across the device. PCB trace/via resistance and
inductance prevent the local load decoupling from causing the oscillation during the transient start up phase.
Note: if the TS432I/432AI/432BI is located right at the load, so the load decoupling capacitor is directly across it, then this capacitor
will have to be ≤1nF or ≥10uF.
Applications Examples
Figure 1: Vka = Vref
Figure 4: Voltage Monitor
Figure 2: Vka > Vref
3/12
Adjustable Precision Shunt Regulator
Figure 5: Output Control for Three Terminal
Fixed Regulator
Figure 3: Off-State Current
L
, are recommended for optional
TS432I
Version: A07