max2235eup Maxim Integrated Products, Inc., max2235eup Datasheet - Page 5

• Manufacturer Part Number: max2235eup
• Description: 3.6v, 1w Autoramping Power Amplifier For 900mhz Applications Integrated Products
• Manufacturer: Maxim Integrated Products, Inc.

(MAX2235 Evaluation Kit, GC = unconnected, f
6, 7, 10
13, 14,
17, 18,
SLUG
PIN
11
12
15
16
19
20
1
2
3
4
5
8
9
1400
1200
1000
RFOUT
RFOUT
NAME
RAMP
SHDN
800
600
400
200
RFIN
GND
GND
GND
V
V
V
V
V
REF
GC
0
CC
CC
CC
CC
CC
0
RISE TIME vs. RAMPING CAPACITANCE
FULL POWER = +20dBm
_______________________________________________________________________________________
FULL POWER = +10dBm
20
RF Input. A DC blocking capacitor in series with RFIN is required. The value of the capacitor depends on
the operating frequency.
GND connection for the input stage (variable-gain amplifier). Connect to the circuit board ground plane
with a separate low-inductance path (via).
Supply Voltage Input for the Input Stage. Bypass with its own 100pF low-inductance capacitor to GND.
Supply Voltage Input for Bias Circuitry. Bypass with its own 100pF low-inductance capacitor and a 1000pF
capacitor to GND, to minimize RF signal coupling into the bias circuits.
Supply Voltage Input for the Input Stage. Bypass with its own 22pF low-inductance capacitor to pins 6 and 7.
GND Connection for the Second-Stage Amplifier (driver). Connect to the circuit board ground plane with a
separate low-inductance path (via).
Supply Voltage Input for the Second Stage. Bypass with its own 220pF and 1000pF low-inductance
capacitors to GND.
Supply Voltage Input for the Second Stage. Connect to pin 8.
Power Ramp Pin. Connect a capacitor between RAMP and REF to provide a gradual linear power-up/down
ramp. See Detailed Description .
Reference Voltage for RAMP Capacitor. The reference is internally set to 1.9V.
GND Connection for the Power Stage. Solder the slug to the circuit board ground plane. Connect pins 13,
14, 17, and 18 to the slug with a straight board trace under the chip.
Power Amplifier Output. See Typical Operating Circuit for an example of a matching network, which pro-
vides optimal output power at 836MHz. Connect to pin 16.
Power Amplifier Output. Connect to pin 15.
Shutdown Pin. Drive SHDN low to turn the device off. Drive above 2.0V to turn the device on. Drive V
> 2.0V and V
Gain-Control Pin. Apply V
relationship. See the Typical Operating Characteristics for a typical relationship.
CAPACITANCE (nF)
40
60
FULL POWER = +30dBm
GC
Amplifier for 900MHz Applications
80
< 0.4V for standby mode.
100
RFIN
Typical Operating Characteristics (continued)
120
+3.6V, 1W Autoramping Power
GC
= 836MHz, V
between 0.6V and 2.3V to control the output power with a monotonic dB/V
CC
= V
SHDN
FUNCTION
= +3.6V, T
1200
1000
800
600
400
200
0
0
FALL TIME vs. RAMPING CAPACITANCE
A
FULL POWER = +10dBm
= +25°C, unless otherwise noted.)
FULL POWER = +30dBm
20
CAPACITANCE (nF)
40
60
Pin Description
FULL POWER = +20dBm
80
100
120
SHDN
5