Linear Technology
DC801A - LT3483ES6 | Inverting DC/DC Converter, Vin= 2.7V-12V, Vout= -15V, Vin = 2.7V-4.2V, Vout= -8V, Iout = 8-40mA*, *See Vin Table
Manual
LT3483 - Product Info
LTspice - Software