HMC1060LP3E Datasheet, PDF (10/16 Pages) Hittite Microwave Corporation – QUAD LOW NOISE HIGH PSRR

v00.1211
HMC1060LP3E
QUAD LOW NOISE HIGH PSRR
LINEAR VOLTAGE REGULATOR
Theory Of Operation
HMC1060LP3E is a four output ultra low noise regulator. The four outputs can be configured to supply anywhere from
1.8 V to 5.2 V. Three outputs (VR1, VR2, and VR3) are configured to supply 3.3 V by default, and have a different
maximum current rating. VR1 is rated at 100 mA maximum, and VR2 and VR3 are rated at a maximum of 50 mA
each. The fourth output, VR4, is configured to supply 5 V by default, and is rated at 300 mA maximum current. Details
specifying various configuration options are available in Output Voltage Configuration section. Default configuration
is shown in Application Schematic section.
The HMC1060LP3E includes a number of features including:
• Thermal Protection feature that disables the outputs of the HMC1060LP3E when the device temperature reaches
a critical temperature. More details are available Thermal Protection section.
• PTAT (Proportional To Absolute Temperature) feature that can be enabled or disabled via an external PTATB pin
of the HMC1060LP3E. PTAT feature, when enabled, scales the output voltage with device temperature in order to
supply optimal supply voltage and current at each temperature in order to maximize the performance of devices
supplied by the HMC1060LP3E. More information about PTAT feature is available in PTAT Feature and Benefits
of PTAT sections.
Thermal Protection
The thermal protection circuitry of the HMC1060LP3E disables the outputs when junction temperature rises to
approximately +150°C. The outputs are kept disabled until the junction temperature cools down by approximately
15°C. The outputs are then re-enabled.
In cases where ambient temperature and/or power dissipation are sufficiently high to re-heat the HMC1060LP3E
repeatedly to +150°C, the thermal protection feature of the HMC1060LP3E will repeat. As a result the thermal
protection feature will cycle the outputs On and Off, protecting the HMC1060LP3E and the components it supplies
from damage. After the overloads, or other fault conditions are removed/changed, the HMC1060LP3E output will
return to normal operation.
If a momentary short-circuit occurs at the output, the associated increase in temperature may activate the thermal
protection circuitry, protecting the HMC1060LP3E and the components it supplies. The device is not protected from
short circuit events lasting longer than 10 seconds.
Operation at Absolute Maximum Ratings levels may damage the HMC1060LP3E immediately. Reliable, long term
operation requires adherence to Electrical Specifications.
Stability Considerations
A regulator is a feedback system. A large capacitor with low ESR (Equivalent Series Resistance) may affect the
feedback dynamics and can result in unstable operation or noise peaking. Two approaches are recommended to
ensure regulator stability:
1. If only one decoupling capacitor is used at the output, the chosen capacitor must have an ESR as defined in
the Stability Requirements table below. This guarantees stability over all loading conditions with the chosen
decoupling capacitor.
2. In the case where several capacitors are connected at the output (which is often the case with noise and spurious
emission sensitive circuits), the recommended approach is to insert a small resistor in series with the load after
the 100 nF feedback capacitor (0.1 Ω resistances shown in the Application Schematic). Recommended ESR
values are shown in the Stability Requirements table below.
Stability Requirements
Total Capacitance at VRx
0.1 µF to 1 µF
> 1 µF
Recommended Equivalent Series
Resistance
200 mΩ
100 mΩ
For price, delivery and to place orders: Hittite Microwave Corporation, 2 Elizabeth Drive, Chelmsford, MA 01824
Phone: [phone] Fax: [phone] Order On-line at www.hittite.com
10
Application Support: Phone: [phone] or [e-mail]