MIC26903Z

The Micrel MIC26903-ZA is a constant-frequency, synchronous buck regulator featuring a unique adaptive ON-time control architecture. The MIC26903-ZA operates over an input supply range of 4.5V to 28V and provides a regulated output of up to 9A of output current. The output voltage is adjustable down to 0.6V with a guaranteed accuracy of ±1%, and the device operates at a switching frequency of 600kHz.

Hyper Speed Control™ architecture allows for ultra-fast transient response while reducing the output capacitance and also makes (High VIN)/(Low VOUT) operation possible. This adaptive tON ripple control architecture combines the advantages of fixed-frequency operation and fast transient response in a single device.

The MIC26603-ZA offers a full suite of features to ensure protection of the IC during fault conditions. These include under voltage lockout to ensure proper operation under power-sag conditions, internal soft-start to reduce inrush current, foldback current limit, "hiccup mode" short-circuit protection, and thermal shutdown. An open-drain Power Good (PG) pin is provided.

Features
  • Hyper Speed Control™ architecture enables
  • High Delta V operation (VIN = 28V and VOUT = 0.6V)
  • Small output capacitance
  • 4.5V to 28V voltage input
  • 9A output current capability and 95% peak efficiency
  • Adjustable output voltage from 0.6V to 5.5V
  • ±1% feedback accuracy
  • Any Capacitor™ stable - zero-to-high ESR
  • 600kHz switching frequency
  • No external compensation
  • Power Good (PG) output
  • Foldback I-limit and "hiccup" mode short-circuit protection
  • Supports safe startup into a pre-biased load
  • -40°C to +125°C junction temperature range
  • Available in 28-pin 5mm — 6mm QFN package
Parameter
Parameter Name Value Value
Regulator Type Step Down (Buck) Step Down (Buck)
# of Outputs 1 1
Input Voltage Range Min (V) 4.5 4.5
Input Voltage Range Max (V) 28 28
Output Voltage Range Min (V) 0.6 0.6
Output Voltage Range Max (V) 5.5 5.5
Output Current (A) max 9 9
Quiescent Current (mA) typ 0.73 0.73
Switching Frequency (kHz) 600 600
Synchronous Rectifier Yes Yes
Operating Temp Range -40 to 125 -40 to 125
Vfb (V) 0.6 0.6
Duty Cycle Max (%) 0.82 0.82
SHUTDOWN Current (µA) (Typ) 5 5
Documents
MIC26903-ZA - 28V, 9A Hyper Speed Control? Synchronous DC-to-DC Buck RegulatorData Sheets11/05/20151329KB
MIC26903-ZA - 28V, 9A Hyper Speed Control? Synchronous DC-to-DC Buck Regulator MIC26903Z